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Document and Entity Information - USD ($)	12 Months Ended
Document and Entity Information - USD ($)	Dec. 31, 2019	Mar. 12, 2020	Jun. 30, 2019
Cover [Abstract]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2019
Document Annual Report	true
Document Transition Report	false
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	FY
Entity Registrant Name	RBB BANCORP
Entity Central Index Key	0001499422
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	No
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Filer Category	Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		19,960,421
Entity Public Float			$ 328,999,122
Entity Interactive Data Current	Yes
Entity Tax Identification Number	27-2776416
Entity File Number	001-38149
Entity Incorporation, State or Country Code	CA
Entity Address, Address Line One	1055 Wilshire Blvd.
Entity Address, Address Line Two	12th floor
Entity Address, City or Town	Los Angeles
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	90017
City Area Code	213
Local Phone Number	627-9888
Title of each class	Common Stock, No Par Value
Trading Symbol	RBB
Name of exchange on which registered	NASDAQ
Documents Incorporated by Reference	Portions of the Registrant’s Definitive Proxy Statement relating to the Annual Meeting of Shareholders, scheduled to be held on May 13, 2020, are incorporated by reference into Part III of this Report.

CONSOLIDATED BALANCE SHEETS - USD ($)	Dec. 31, 2019	Dec. 31, 2018
Assets
Cash and due from banks	$ 114,763,000	$ 147,685,000
Federal funds sold and other cash equivalents	67,000,000
Cash and cash equivalents	181,763,000	147,685,000
Interest-earning deposits in other financial institutions	600,000	600,000
Securities:
Available for sale	126,069,000	73,762,000
Held to maturity (fair value of $8,632 and $9,940 at December 31, 2019 and December 31, 2018, respectively)	8,332,000	9,961,000
Mortgage loans held for sale	108,194,000	434,522,000
Loans held for investment:
Real estate	1,852,206,000	1,762,864,000
Commercial and other	349,391,000	387,474,000
Total loans	2,201,597,000	2,150,338,000
Unaccreted discount on acquired loans	(5,067,000)	(9,229,000)
Deferred loan costs (fees), net	404,000	906,000
Total loans, net of deferred loan fees	2,196,934,000	2,142,015,000
Allowance for loan losses	(18,816,000)	(17,577,000)
Net loans	2,178,118,000	2,124,438,000
Premises and equipment	16,813,000	17,307,000
Federal Home Loan Bank (FHLB) stock	15,000,000	9,707,000
Net deferred tax assets	2,326,000	4,642,000
Other real estate owned (OREO)	293,000	1,101,000
Cash surrender value of life insurance (BOLI)	34,353,000	33,578,000
Goodwill	58,563,000	58,383,000
Servicing assets	17,083,000	17,370,000
Core deposit intangibles	6,100,000	7,601,000
Accrued interest and other assets	34,928,000	33,345,000
Total assets	2,788,535,000	2,974,002,000
Deposits:
Noninterest-bearing demand	458,763,000	438,764,000
Savings, NOW and money market accounts	537,490,000	579,247,000
Time deposits $250,000 and under	655,303,000	532,395,000
Time deposits over $250,000	597,382,000	593,635,000
Total deposits	2,248,938,000	2,144,041,000
Reserve for unfunded commitments	826,000	688,000
FHLB advances	0	319,500,000
Long-term debt, net of debt issuance costs	104,049,000	103,708,000
Subordinated debentures	9,673,000	9,506,000
Accrued interest and other liabilities	17,359,000	21,938,000
Total liabilities	2,380,845,000	2,599,381,000
Commitments and contingencies - Note 7 and 13
Shareholders' equity:
Preferred Stock - 100,000,000 shares authorized, no par value; none outstanding
Common Stock - 100,000,000 shares authorized, no par value; 20,030,866 shares issued and outstanding at December 31, 2019 and 20,000,022 shares at December 31, 2018	290,395,000	288,610,000
Additional paid-in capital	4,938,000	5,659,000
Retained earnings	112,046,000	81,618,000
Non-controlling interest	72,000	72,000
Accumulated other comprehensive income (loss), net	239,000	(1,338,000)
Total shareholders’ equity	407,690,000	374,621,000
Total liabilities and shareholders’ equity	$ 2,788,535,000	$ 2,974,002,000

CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Statement Of Financial Position [Abstract]
Securities held to maturity, fair value	$ 8,632	$ 9,940
Preferred stock, shares authorized	100,000,000	100,000,000
Preferred stock, par value
Preferred stock, shares outstanding	0	0
Common stock, shares authorized	100,000,000	100,000,000
Common stock, par value
Common stock, shares issued	20,030,866	20,000,022
Common stock, shares outstanding	20,030,866	20,000,022

CONSOLIDATED STATEMENTS OF INCOME - USD ($)	12 Months Ended
CONSOLIDATED STATEMENTS OF INCOME - USD ($)	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Interest and dividend income:
Interest and fees on loans	$ 135,159,000	$ 97,480,000	$ 70,289,000
Interest on interest-earning deposits	1,785,000	1,002,000	940,000
Interest on investment securities	2,652,000	2,351,000	1,406,000
Dividend income on FHLB stock	1,079,000	650,000	472,000
Interest on federal funds sold and other	1,050,000	632,000	997,000
Total interest income	141,725,000	102,115,000	74,104,000
Interest expense:
Interest on savings deposits, now and money market accounts	4,886,000	4,408,000	2,382,000
Interest on time deposits	29,347,000	12,548,000	7,891,000
Interest on subordinated debentures and long-term debt	7,698,000	4,083,000	3,629,000
Interest on other borrowed funds	2,930,000	2,606,000	36,000
Total interest expense	44,861,000	23,645,000	13,938,000
Net interest income	96,864,000	78,470,000	60,166,000
Provision (recapture) for credit losses	2,390,000	4,469,000	(1,053,000)
Net interest income after provision (recapture) for credit losses	94,474,000	74,001,000	61,219,000
Noninterest income:
Service charges, fees and other	4,072,000	2,679,000	2,111,000
Gain on sale of loans	9,893,000	7,126,000	9,318,000
Loan servicing fees, net of amortization	3,383,000	850,000	722,000
Recoveries on loans acquired in business combinations	143,000	1,385,000	84,000
Unrealized gain on equity investments	147,000
Increase in cash surrender value of life insurance	775,000	797,000	824,000
Gain on sale of securities	7,000	5,000
(Loss) gain on sale of OREO	(106,000)		142,000
Gain on sale of fixed assets	6,000
Total noninterest income	18,320,000	12,842,000	13,201,000
Noninterest expense:
Salaries and employee benefits	32,909,000	23,254,000	16,821,000
Occupancy and equipment expenses	9,750,000	4,554,000	2,940,000
Data processing	3,699,000	2,323,000	1,622,000
Legal and professional	1,832,000	1,714,000	331,000
Office expenses	1,257,000	890,000	679,000
Marketing and business promotion	1,308,000	1,143,000	837,000
Insurance and regulatory assessments	900,000	951,000	799,000
Core deposit premium	1,501,000	575,000	355,000
OREO expenses	337,000	24,000	28,000
Merger expenses	471,000	1,658,000	37,000
Other expenses	3,509,000	3,551,000	3,174,000
Total noninterest expense	57,473,000	40,637,000	27,623,000
Income before income taxes	55,321,000	46,206,000	46,797,000
Income tax expense	16,112,000	10,101,000	21,269,000
Net income	$ 39,209,000	$ 36,105,000	$ 25,528,000
Net income per share
Basic	$ 1.96	$ 2.11	$ 1.81
Diluted	1.92	2.01	1.68
Cash dividends declared per common share	$ 0.40	$ 0.35	$ 0.38
Weighted-average common shares outstanding
Basic	20,017,306	17,151,222	14,078,281
Diluted	20,393,424	17,967,653	15,238,365

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Statement Of Income And Comprehensive Income [Abstract]
Net income	$ 39,209	$ 36,105	$ 25,528
Other comprehensive income (loss):
Unrealized gains (losses) on securities available for sale, Change in unrealized gains (losses)	2,248	(1,266)	(176)
Unrealized gains (losses) on securities available for sale, Reclassification of gains recognized in net income	(7)	(5)
Unrealized gains (losses) on securities available for sale	2,241	(1,271)	(176)
Related income tax effect, Change in unrealized (gains) losses	(666)	376	72
Related income tax effect, Reclassification of gains recognized in net income	2
Related income tax effect	(664)	376	72
Total other comprehensive income (loss)	1,577	(895)	(104)
Total comprehensive income	$ 40,786	$ 35,210	$ 25,424

CONSOLIDATED STATEMENT OF CHANGES IN SHAREHOLDERS' EQUITY - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Retained Earnings	Non-Controlling Interest	Accumulated Other Comprehensive Income (Loss)
Beginning balance at Dec. 31, 2016	$ 181,585	$ 142,651	$ 8,417	$ 30,784		$ (267)
Beginning balance, shares at Dec. 31, 2016		12,827,803
Net income	25,528			25,528
Stock-based compensation	779		779
Cash dividend	(5,118)			(5,118)
Stock options exercised, net of expense recognized	2,296	$ 3,066	(770)
Stock options exercised, net of expense recognized, shares		223,334
Issuance of common stock, net of issuance costs	60,210	$ 60,210
Issuance of common stock, net of issuance costs, shares		2,857,756
Other comprehensive (loss) income, net of taxes	(104)					(104)
Reclassification of stranded tax effects from change in tax rates				72		(72)
Ending balance at Dec. 31, 2017	265,176	$ 205,927	8,426	51,266		(443)
Ending balance, shares at Dec. 31, 2017		15,908,893
Net income	36,105			36,105
Stock-based compensation	684		684
Restricted stock awarded, shares		43,425
Cash dividend	(5,753)			(5,753)
Stock options exercised, net of expense recognized	9,629	$ 13,080	(3,451)
Stock options exercised, net of expense recognized, shares		1,035,942
Issuance of common stock for acquisition	69,603	$ 69,603
Issuance of common stock for acquisition, shares		3,011,762
Non-controlling interest	72				$ 72
Other comprehensive (loss) income, net of taxes	(895)					(895)
Ending balance at Dec. 31, 2018	$ 374,621	$ 288,610	5,659	81,618	72	(1,338)
Ending balance, shares at Dec. 31, 2018	20,000,022	20,000,022
Net income	$ 39,209			39,209
Stock-based compensation	689		689
Restricted stock vested		$ 425	(425)
Cash dividend	(8,033)			(8,033)
Stock options exercised, net of expense recognized	$ 2,817	$ 3,802	(985)
Stock options exercised, net of expense recognized, shares	200,629	200,629
Repurchase of common stock	$ (3,190)	$ (2,442)		(748)
Repurchase of common stock,shares	(169,785)	(169,785)
Other comprehensive (loss) income, net of taxes	$ 1,577					1,577
Ending balance at Dec. 31, 2019	$ 407,690	$ 290,395	$ 4,938	$ 112,046	$ 72	$ 239
Ending balance, shares at Dec. 31, 2019	20,030,866	20,030,866

CONSOLIDATED STATEMENT OF CHANGES IN SHAREHOLDERS' EQUITY (Parenthetical) $ in Thousands	12 Months Ended
	Dec. 31, 2017 USD ($)
Statement Of Stockholders Equity [Abstract]
Issuance of common stock, net of issuance costs	$ 5,518

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($)	12 Months Ended
CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($)	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Operating activities
Net income	$ 39,209,000	$ 36,105,000	$ 25,528,000
Adjustments to reconcile net income to net cash from Operating activities:
Depreciation and amortization of premises, and equipment	1,914,000	1,833,000	525,000
Net accretion of securities, loans, deposits, and other	(2,845,000)	(1,754,000)	(4,801,000)
Unrealized gain on equity securities	(147,000)
Amortization of investment in affordable housing tax credits	900,000	644,000	316,000
Amortization of intangible assets	4,856,000	3,302,000	1,845,000
Provision (recapture) for loan losses	2,390,000	4,469,000	(1,053,000)
Stock-based compensation	689,000	684,000	779,000
Deferred tax benefit	1,503,000	(383,000)	5,083,000
Gain on sale of securities	(7,000)	(5,000)
Gain on sale of loans	(9,893,000)	(7,126,000)	(9,318,000)
Loss (gain) on sale of OREO	106,000		(142,000)
Gain on sale of fixed assets	(6,000)
Increase in cash surrender value of life insurance	(775,000)	(797,000)	(824,000)
Loans originated and purchased for sale, net	(77,514,000)	(413,450,000)	(254,629,000)
Proceeds from loans sold	521,594,000	301,894,000	265,497,000
Other items	(5,506,000)	(10,064,000)	(23,000)
Net cash provided by (used in) operating activities	476,468,000	(84,648,000)	28,783,000
Securities available for sale:
Purchases	(197,386,000)	(74,171,000)	(29,557,000)
Maturities, prepayments and calls	141,537,000	64,008,000	4,353,000
Sales	6,143,000	44,591,000	0
Securities held to maturity:
Maturities, prepayments and calls	1,590,000		1,100,000
Redemption of Federal Home Loan Bank stock	808,000
Purchase of Federal Home Loan Bank stock and other equity securities, net	(7,741,000)	(11,077,000)	(837,000)
Net increase of investment in qualified affordable housing projects	(2,598,000)	(1,911,000)	(5,000,000)
Net increase in loans	(161,426,000)	(366,415,000)	(218,897,000)
Proceeds from sales of OREO	1,053,000		257,000
Purchase of bank owned life insurance			(10,000,000)
Net cash paid in connection with acquisition		25,073,000
Proceeds from sale of fixed assets	17,000
Purchases of premises and equipment	(1,350,000)	(2,488,000)	(684,000)
Net cash used in investing activities	(219,353,000)	(322,390,000)	(264,446,000)
Financing activities
Net (decrease) increase in demand deposits and savings accounts	(21,758,000)	(9,807,000)	226,382,000
Net increase (decrease) in time deposits	126,627,000	186,588,000	(41,772,000)
Net (decrease) increase in FHLB advances	(319,500,000)	170,000,000	25,000,000
Cash dividends paid	(8,033,000)	(5,753,000)	(5,118,000)
Issuance of subordinated debentures, net of issuance costs		54,018,000
Issuance of common stock, net of issuance costs			60,210,000
Common stock repurchased, net of repurchased costs	(3,190,000)
Exercise of stock options	2,817,000	9,629,000	2,296,000
Net cash (used in) provided by financing activities	(223,037,000)	404,675,000	266,998,000
Net increase (decrease) in cash and cash equivalents	34,078,000	(2,363,000)	31,335,000
Cash and cash equivalents at beginning of period	147,685,000	150,048,000	118,713,000
Cash and cash equivalents at end of period	181,763,000	147,685,000	150,048,000
Cash paid during the period:
Interest paid	45,702,000	19,993,000	13,848,000
Taxes paid	14,470,000	9,335,000	16,935,000
Non-cash investing and financing activities:
Transfer of loan to available for sale securities			1,000,000
Transfer from loans to other real estate owned	974,000	808,000
Transfer of loans to held for sale, net	107,859,000	186,503,000	165,651,000
Loan to facilitate OREO	623,000	104,000	425,000
Net change in unrealized holding (loss) gain on securities available for sale	$ 2,241,000	$ (1,271,000)	$ (176,000)

Business Description

12 Months Ended

Dec. 31, 2019

Business Description [Abstract]

Business Description

NOTE 1 - BUSINESS DESCRIPTION

RBB Bancorp is a financial holding company registered under the Bank Holding Company Act of 1956, as amended. RBB Bancorp’s principal business is to serve as the holding company for its wholly-owned banking subsidiaries, Royal Business Bank ("Bank") and RBB Asset Management Company ("RAM"), collectively referred to herein as "the Company". At December 31, 2019, the Company had total assets of $2.8 billion, gross consolidated loans (held for investment and held for sale) of $2.3 billion, total deposits of $2.2 billion and total stockholders' equity of $407.7 million. On July 31, 2017, the Company completed its initial public offering of 3,750,000 shares at a price to the public of $23.00 per share. The Company’s stock trades on the Nasdaq Global Select Market under the symbol “RBB”.

The Bank provides business banking services to the Chinese-American communities in Los Angeles County, Orange County, Ventura County and in Las Vegas and New York City metropolitan area, including remote deposit, E-banking, mobile banking, commercial and investor real estate loans, business loans and lines of credit, Small Business Administration (“SBA”) 7A and 504 loans, mortgage loans, trade finance and a full range of depository accounts.

The Company operates full-service banking offices in Arcadia, Cerritos, Diamond Bar, Irvine, Los Angeles, Monterey Park, Oxnard, Rowland Heights, San Gabriel, Silver Lake, Torrance, West Los Angeles, and Westlake Village, California; Las Vegas, Nevada; and Manhattan, Brooklyn, Flushing, and Elmhurst, New York. The Company's primary source of revenue is providing loans to customers, who are predominately small and middle-market businesses and individuals.

The Company generates its revenue primarily from interest received on loans and leases and, to a lesser extent, from interest received on investment securities. The Company also derives income from noninterest sources, such as fees received in connection with various lending and deposit services, loan servicing, gain on sales of loans and wealth management services. The Company’s principle expenses include interest expense on deposits and subordinated debentures, and operating expenses, such as salaries and employee benefits, occupancy and equipment, data processing, and income tax expense.

As part of the FAIC acquisition, the Company acquired FAIB Capital Corp. (FAICC) that was formed on January 29, 2014. FAICC is a real estate investment trust subsidiary of the Bank.

The Company has completed five acquisitions from July 8, 2011 through October 15, 2018, including the acquisition of First American International Corp. (“FAIC”) and its wholly-owned subsidiary, First American International Bank (“FAIB”), in which the FAIC acquisition closed on October 15, 2018. FAIB operated three branches in Queens, two in Manhattan, and two in Brooklyn, New York with an operating center and loan production offices in Brooklyn and an administrative center in Manhattan. As part of the FAIC acquisition, the Company acquired FAIB Capital Corp. (“FAICC”) that was formed on January 29, 2014. FAICC is a real estate investment trust subsidiary of the Bank. See Note 3 – Acquisition, for more information about the FAIC acquisition transactions. All of the Company’s acquisitions have been accounted for using the acquisition method of accounting and, accordingly, the operating results of the acquired entities have been included in the consolidated financial statements from their respective acquisition dates.

Basis of Presentation and Summary of Significant Accounting Policies

12 Months Ended

Dec. 31, 2019

Accounting Policies [Abstract]

Basis of Presentation and Summary of Significant Accounting Policies

NOTE 2 - BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

Basis of Presentation

The accompanying consolidated financial statements and notes thereto of the Company have been prepared in accordance with the rules and regulations of the Securities and Exchange Commission (“SEC”) for Form 10-K and conform to practices within the banking industry and include all of the information and disclosures required by accounting principles generally accepted in the United States of America (“GAAP”) for financial reporting.

Principles of Consolidation and Nature of Operations

The accompanying consolidated financial statements include the accounts of RBB Bancorp and its wholly-owned subsidiaries Royal Business Bank ("Bank") and RBB Asset Management Company ("RAM"), collectively referred to herein as "the Company". All significant intercompany transactions have been eliminated.

RBB Bancorp was formed in January 2011 as a bank holding company, and in 2018 changed to a financial holding company. RAM was formed in 2012 to hold and manage problem assets acquired in business combinations.

In connection with the 2018 acquisition of FAIC, the Company acquired a real estate investment trust (“REIT”) as a subsidiary of the Bank and is a New York State corporation. In addition to the REIT, the Company acquired four inactive subsidiaries: FAIC Insurance Services (a New York corporation formed in 2006), P4G8, LLC, FAIB Reacquisitions I, LLC and FAIB REO Acquisition II, LLC. FAIC Insurance services was dissolved in January 2020; the other three were dissolved in 2019.

We acquired two statutory business trusts: TFC Statutory Trust in 2016 and FAIC Statutory Trust in 2018. These trusts issued trust preferred securities representing undivided preferred beneficial interests in the assets of the Trusts. The proceeds of these trust preferred securities were invested in certain securities issued by us, with similar terms to the relevant series of securities issued by the Trusts, which we refer to as subordinated debentures.

RBB Bancorp has no significant business activity other than its investments in Royal Business Bank and RAM. Parent only condensed financial information on RBB Bancorp is provided in Note 22.

Use of Estimates in the Preparation of Financial Statements

The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. It is reasonably possible our estimate of the allowance for loan losses and the fair value of mortgage servicing rights could change as actual results could differ from those estimates.

Cash and Cash Equivalents

Cash and cash equivalents include cash and due from banks, term federal funds sold and interest-bearing deposits in other financial institutions with original maturities of less than 90 days. Net cash flows are reported for customer loan and deposit transactions and interest-bearing deposits in other financial institutions.

Cash and Due from Banks

Banking regulations require that banks maintain a percentage of their deposits as reserves in cash or on deposit with the Federal Reserve Bank. The reserves required to be held as of December 31, 2019 and 2018 were $29.5 million and $24.5 million, respectively. The Company maintains amounts in due from bank accounts, which may exceed federally insured limits. The Company has not experienced any losses in such accounts.

Interest-Bearing Deposits in Other Financial Institutions

Interest-bearing deposits in other financial institutions not included in cash and cash equivalents are carried at cost and generally mature in one year or less.

Investment Securities

Investment securities are classified as held to maturity and carried at amortized cost when management has the positive intent and ability to hold them to maturity. Debt securities not classified as held to maturity are classified as available for sale. Securities available for sale are carried at fair value, with unrealized holding gains and losses reported in other comprehensive income, net of tax.

Interest income includes amortization of purchase premiums or discounts. Premiums and discounts on securities are amortized on the level-yield method without anticipating prepayments. Gains and losses on sales are recorded on the trade date and determined using the specific identification method.

Management evaluates debt securities for other-than-temporary impairment ("OTTI") on at least a quarterly basis, and more frequently when economic or market conditions warrant such an evaluation. For securities in an unrealized loss position, management considers the extent and duration of the unrealized loss, and the financial condition and near-term prospects of the issuer. Management also assesses whether it intends to sell, or it is more likely than not that it will be required to sell, a security in an unrealized loss position before recovery of its amortized cost basis. If either of the criteria regarding intent or requirement to sell is met, the entire difference between amortized cost and fair value is recognized as impairment through earnings. For debt securities that do not meet the aforementioned criteria, the amount of impairment is split into two components as follows; OTTI related to credit loss, which must be recognized in the income statement and; OTTI related to other factors, which is recognized in other comprehensive income. The credit loss is defined as the difference between the present value of the cash flows expected to be collected and the amortized cost basis.

Loans Held For Sale

Mortgage loans originated or acquired and intended for sale in the secondary market are carried at the lower of aggregate cost or fair value, as determined by outstanding commitments from investors. Net unrealized losses, if any, are recorded as a valuation allowance and charged to earnings. Loans held for sale consist primarily of first trust deed mortgages on single-family residential properties located in California.

Mortgage loans held for sale are generally sold with servicing rights retained. The carrying value of mortgage loans sold is determined by reducing the amount allocated to the servicing right, when applicable. Gains and losses on sales of mortgage loans are based on the difference between the selling price and the carrying value of the related loans sold.

Loans

Loans receivable that management has the intent and ability to hold for the foreseeable future or until maturity or payoff are reported at their outstanding unpaid principal balances reduced by any charge-offs or specific valuation accounts and net of any deferred fees or costs on originated loans, or unamortized premiums or discounts on purchased loans. Loan origination fees and certain direct origination costs are deferred and recognized in interest income using the level-yield method without anticipating prepayments.

Premiums and discounts on loans purchased are grouped by type and certain common risk characteristics and amortized or accreted as an adjustment of yield over the weighted-average remaining contractual lives of each group of loans, adjusted for prepayments when applicable, using methodologies which approximate the interest method.

Loans on which the accrual of interest has been discontinued are designated as nonaccrual loans. The accrual of interest on loans is discontinued when principal or interest is past due 90 days or when, in the opinion of management, there is reasonable doubt as to collectability based on contractual terms of the loan. When loans are placed on nonaccrual status, all interest previously accrued but not collected is reversed against current period interest income. Income on nonaccrual loans is subsequently recognized only to the extent that cash is received and the loan's principal balance is deemed collectible. Interest accruals are resumed on such loans only when they are brought current with respect to interest and principal and when, in the judgment of management, the loans are estimated to be fully collectible as to all principal and interest.

Allowance for Loan Losses

The allowance for loan losses is a valuation allowance for probable incurred credit losses. Loan losses are charged against the allowance when management believes the uncollectability of a loan balance is confirmed. Subsequent recoveries, if any, are credited to the allowance. Management estimates the allowance balance required using past loan loss experience, the nature and volume of the portfolio, information about specific borrower situations and estimated collateral values, economic conditions, and other factors. Allocations of the allowance may be made for specific loans, but the entire allowance is available for any loan that, in management's judgment, should be charged-off. Amounts are charged-off when available information confirms that specific loans or portions thereof, are uncollectible. This methodology for determining charge-offs is consistently applied to each segment.

The Company determines a separate allowance for each portfolio segment. The allowance consists of specific and general reserves. Specific reserves relate to loans that are individually classified as impaired. A loan is impaired when, based on current information and events, it is probable that the Company will be unable to collect all amounts due according to the contractual terms of the loan agreement. Factors considered in determining impairment include payment status, collateral value and the probability of collecting all amounts when due. Measurement of impairment is based on the expected future cash flows of an impaired loan, which are to be discounted at the loan's effective interest rate, or measured by reference to an observable market value, if one exists, or the fair value of the collateral for a collateral-dependent loan. The Company selects the measurement method on a loan-by-loan basis except that collateral-dependent loans for which foreclosure is probable are measured at the fair value of the collateral.

The Company recognizes interest income on impaired loans based on its existing methods of recognizing interest income on nonaccrual loans. Loans, for which the terms have been modified resulting in a concession, and for which the borrower is experiencing financial difficulties, are considered troubled debt restructurings and classified as impaired with measurement of impairment as described above.

If a loan is impaired, a portion of the allowance is allocated so that the loan is reported, net, at the present value of estimated future cash flows using the loan's existing rate or at the fair value of collateral if repayment is expected solely from the collateral.

General reserves cover non-impaired loans and are based on historical loss rates of peer institutions for each portfolio segment, adjusted for the effects of qualitative or environmental factors that are likely to cause estimated credit losses as of the evaluation date to differ from the portfolio segment's historical loss experience. Qualitative factors include consideration of the following: changes in lending policies and procedures; changes in economic conditions, changes in the nature and volume of the portfolio; changes in the experience, ability and depth of lending management and other relevant staff; changes in the volume and severity of past due, nonaccrual and other adversely graded loans; changes in the loan review system; changes in the value of the underlying collateral for collateral-dependent loans; concentrations of credit and the effect of other external factors such as competition and legal and regulatory requirements.

Portfolio segments identified by the Company include real estate, commercial and other loans. Relevant risk characteristics for these portfolio segments generally include debt service coverage, loan-to-value ratios, and financial performance.

Certain Acquired Loans

As part of business acquisitions, the Company acquires certain loans that have shown evidence of credit deterioration since origination. These acquired loans are recorded at the allocated fair value, such that there is no carryover of the seller's allowance for loan losses. Such acquired loans are accounted for individually. The Company estimates the amount and timing of expected cash flows for each purchased loan, and the expected cash flows in excess of the allocated fair value is recorded as interest income over the remaining life of the loan (accretable yield). The excess of the loan's contractual principal and interest over expected cash flows is not recorded (non-accretable difference). Over the life of the loan, expected cash flows continue to be estimated. If the present value of expected cash flows is less than the carrying amount, a loss is recorded through the allowance for loan losses. If the present value of expected cash flows is greater than the carrying amount, it is recognized as part of future interest income.

Servicing Rights

When mortgage and Small Business Administration ("SBA") loans are sold with servicing retained, servicing rights are initially recorded at fair value with the income statement effect recorded in gains on sales of loans. Fair value is based on a valuation model that calculates the present value of estimated future net servicing income. All classes of servicing assets are subsequently measured using the amortization method which requires servicing rights to be amortized into noninterest income in proportion to, and over the period of, the estimated future net servicing income of the underlying loans.

Servicing rights are evaluated for impairment based upon the fair value of the rights as compared to carrying amount. Impairment is recognized through a valuation allowance for an individual grouping, to the extent that fair value is less than the carrying amount. If the Company later determines that all or a portion of the impairment no longer exists for a particular grouping, a reduction of the allowance may be recorded as an increase to income.

Servicing fee income, which is reported on the income statement as loan servicing fees, net of amortization, is recorded for fees earned for servicing loans. The fees are based on a contractual percentage of the outstanding principal. The amortization of mortgage servicing rights is netted against loan servicing fee income.

Transfers of Financial Assets

Transfers of financial assets are accounted for as sales, when control over the assets has been relinquished. Control over transferred assets is deemed to be surrendered when the assets have been isolated from the Company, the transferee obtains the right (free of conditions that constrain it from taking advantage of that right) to pledge or exchange the transferred assets, and the Company does not maintain effective control over the transferred assets through an agreement to repurchase them before their maturity.

Gains on sales of mortgage, SBA and CRE loans totaled $9.9 million, $7.1 million, and $9.3 million in 2019, 2018, and 2017, respectively. Gains on sale of mortgage loans totaled $8.2 million, $4.3 million, and $3.7 million, and gains on sale of SBA loans totaled $1.5 million, $2.8 million, and $5.6 million in 2019, 2018, and 2017 respectively. Gains on sale of CRE totaled $152,000 in 2019 and none in 2018 and 2017.

Premises and Equipment

Land is carried at cost. Premises, leasehold improvements and equipment are carried at cost less accumulated depreciation and amortization. Depreciation is computed using the straight-line method over the estimated useful lives, which is thirty years for premises and ranges from three to ten years for leasehold improvements and equipment. Leasehold improvements are amortized using the straight-line method over the estimated useful lives of the improvements or the remaining lease term, whichever is shorter. Expenditures for betterments or major repairs are capitalized and those for ordinary repairs and maintenance are charged to operations as incurred.

Other Real Estate Owned

Real estate acquired by foreclosure or deed in lieu of foreclosure is recorded at fair value at the date of foreclosure, establishing a new cost basis by a charge to the allowance for loan losses, if necessary. Other real estate owned is carried at the lower of the Company's carrying value of the property or its fair value, less estimated carrying costs and costs of disposition. Fair value is based on current appraisals less estimated selling costs. Any subsequent write-downs are charged against operating expenses and recognized as a valuation allowance. Operating expenses and related income of such properties and gains and losses on their disposition are included in other operating income and expenses.

Goodwill and Other Intangible Assets

Goodwill is generally determined as the excess of the fair value of the consideration transferred, plus the fair value of any noncontrolling interests in the acquiree, over the fair value of the net assets acquired and liabilities assumed as of the acquisition date. Goodwill resulting from whole bank acquisitions is not amortized, but tested for impairment at least annually. The Company has selected December 31 as the date to perform the annual impairment test. Goodwill amounted to $58.6 million and $58.4 million as of December 31, 2019 and 2018, respectively, and is the only intangible asset with an indefinite life on the balance sheet. No impairment was recognized on goodwill during 2019 and 2018.

Other intangible assets consist of core deposit intangible ("CDI") assets arising from whole bank acquisitions. CDI assets are amortized on an accelerated method over their estimated useful life of 8 to 10 years. CDI was recognized in the 2013 acquisition of Los Angeles National Bank and in the 2016 acquisition of TFC Holding Company and in the 2018 acquisition of FAIC. The unamortized balance as of December 31, 2019 and 2018 was $6.1 million and $7.6 million, respectively. Accumulated amortization as of December 31, 2019 and 2018 was $3.1 million and $1.6 million, respectively. CDI amortization expense was $1.5 million, $575,000, and $355,000 in 2019, 2018 and 2017, respectively.

Estimated CDI amortization expense for the next 5 years is as follows (dollars in thousands):

(dollars in thousands)
Year ending December 31:
2020	$	1,285
2021		1,056
2022		879
2023		749
2024		638
Thereafter		1,493
Total	$	6,100

Bank Owned Life Insurance

The Company has purchased life insurance policies on a select group of employees and directors. Bank owned life insurance (“BOLI”) is recorded at the amount that can be realized under the insurance contract at the balance sheet date, which is the cash surrender value adjusted for other charges or other amounts due that are probable at settlement. Increases of the cash value of these policies, as well as insurance proceeds received, are recorded in the other noninterest income and are not subject to income tax for as long as they are held for the life of the covered employee and director.

FHLB Stock and Other Equity Securities

The Company is a member of the FHLB system. Members are required to own a certain amount of stock based on the level of borrowings and other factors, and may invest in additional amounts. FHLB stock is carried at cost, classified as a restricted security, and periodically evaluated for impairment based on ultimate recovery of par value. Both cash and stock dividends are reported as income.

The Company also owns equity investment in banker’s bank stock. The Company adopted ASU 2016-01 on January 1, 2019, and elected the measurement alternative for measuring equity securities without readily determinable fair values at cost less impairment, plus or minus observable price changes in orderly transactions. As of December 31, 2019, the carrying amount of equity securities without readily determinable fair values were $324,000 for PCBB and $100,000 for ACBB. An estimated gain of $107,000 from PCBB and $40,000 from ACBB based on observable activity in these securities was recorded in the first quarter of 2019.

As of December 31, 2019 the Company had several CRA equity investments without readily determinable fair values in the amount of $11.8 million, and $10.0 million at December 31, 2018.

Stock-Based Compensation

Stock option compensation expense is calculated based on the fair value of the award at the grant date for those options expected to vest and is recognized as an expense over the vesting period of the grant using the straight-line method. The Company uses the Black-Scholes option pricing model to estimate the value of granted options. This model takes into account the option exercise price, the expected life, the current price of the underlying stock, the expected volatility of the Company’s stock, expected dividends on the stock and a risk-free interest rate. The Company estimates the expected volatility based on the Company’s historical stock prices for the period corresponding to the expected life of the stock options. Restricted stock units are valued at the closing price of the Company’s stock on the date of the grant. Compensation cost is recognized for stock options and restricted stock awards issued to employees and directors, based on the fair value of these awards. This cost is recognized over the period which an employee is required to provide services in exchange for the award, generally defined as the vesting period. When the options are exercised, the Company’s policy is to issue new shares of stock. The Company’s accounting policy is to recognize forfeitures as they occur.

Income Taxes

The Company files its income taxes on a consolidated basis with its subsidiaries. The allocation of income tax expense represents each entity’s proportionate share of the consolidated provision for income taxes. Income tax expense is the total of the current year income tax due or refundable and the change in deferred tax assets and liabilities. Deferred tax assets and liabilities are the expected future tax amounts for the temporary differences between carrying amounts and tax bases of assets and liabilities, computed using enacted tax rates. A valuation allowance, if needed, reduces deferred tax assets to the amount expected to be realized. Tax effects from an uncertain tax position are recognized in the financial statements only if, based on its merits, the position is more likely than not to be sustained on audit by the taxing authorities. Interest and penalties related to uncertain tax positions are recorded as part of income tax expense.

Retirement Plans

The Company established a 401(k) plan in 2010. The Company contributed $570,000, $341,000, and $272,000 in 2019, 2018 and 2017, respectively.

Comprehensive Income

Comprehensive income consists of net income and other comprehensive income. Other comprehensive income includes unrealized gains and losses on securities available for sale.

Financial Instruments

In the ordinary course of business, the Company has entered into off-balance sheet financial instruments consisting of commitments to extend credit, commercial letters of credit, and standby letters of credit as described in Note 13. Such financial instruments are recorded in the financial statements when they are funded.

Earnings Per Share ("EPS")

Basic and diluted EPS are calculated using the two-class method since the Company has issued share-based payment awards considered participating securities because they entitle holders the rights to dividends during the vesting term. The two-class method is an earnings allocation formula that determines net income per share for each class of common stock and participating security according to dividends declared and participation rights in undistributed earnings. Basic EPS excludes dilution and is computed by dividing income available to common shareholders by the weighted-average number of common shares outstanding for the period. Diluted EPS reflects the potential dilution that could occur if securities or other contracts to issue common stock were exercised or converted into common stock or resulted in the issuance of common stock that then shared in the earnings of the entity.

Fair Value Measurement

Fair value is the exchange price that would be received for an asset or paid to transfer a liability (exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. Current accounting guidance establishes a fair value hierarchy, which requires an entity to maximize the use of observable inputs and minimize the use of unobservable inputs when measuring fair value. There are three levels of inputs that may be used to measure fair values:

Level 1: Quoted prices (unadjusted) for identical assets or liabilities in active markets that the entity has the ability to access as of the measurement date.

Level 2: Significant other observable inputs other than Level 1 prices such as quoted prices for similar assets or liabilities; quoted prices in markets that are not active; or other inputs that are observable or can be corroborated by observable market data.

Level 3: Significant unobservable inputs that reflect the Company's own assumptions about the assumptions that market participants would use in pricing an asset or liability.

See Note 17 and Note 18 for more information and disclosures relating to the Company's fair value measurements.

Operating Segments

Management has determined that since generally all of the banking products and services offered by the Company are available in each branch of the Bank, all branches are located within the same economic environment and management does not allocate resources based on the performance of different lending or transaction activities, it is appropriate to aggregate the Bank branches and report them as a single operating segment.

Recent Accounting Pronouncements

When RBB conducted its IPO in 2017, we qualified as an emerging growth company (“EGC”). We will remain an EGC until the earliest of (i) the end of the fiscal year during which we have total annual gross revenues of $1.0 billion or more, (ii) the end of the fiscal year following the fifth anniversary of the completion of our IPO, (iii) the date on which we have, during the previous three-year period, issued more than $1.0 billion in non-convertible debt and (iv) the date on which we are deemed to be a “large accelerated filer” under the Securities Exchange Act of 1934, as amended. We anticipate no longer qualifying as an EGC on January 1, 2023. EGCs are entitled to reduced regulatory and reporting requirements under the Securities Act and the Exchange Act.

In May 2014, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU" or “Update”) 2014-09, Revenue from Contracts with Customers (Topic 606). This Update requires an entity to recognize revenue as performance obligations are met, in order to reflect the transfer of promised goods or services to customers in an amount that reflects the consideration the entity is entitled to receive for those goods or services. The following steps are applied in the updated guidance: (1) identify the contract(s) with a customer; (2) identify the performance obligations in the contract; (3) determine the transaction price; (4) allocate the transaction price to the performance obligations in the contract; and (5) recognize revenue when, or as, the entity satisfies a performance obligation. These amendments are effective for public business entities for annual reporting periods beginning after December 15, 2017, including interim periods within that reporting period. Our revenue is primarily comprised of net interest income on financial assets and financial liabilities, which is explicitly excluded from the scope of ASU 2014-09, and non-interest income. Accordingly, the majority of the Company’s revenues will not be affected. In addition, the standard does not materially impact the timing or measurement of the Company’s revenue recognition as it is consistent with the Company’s existing accounting for contracts within the scope of the standard. As an emerging growth company, the Company adopted ASU 2014-09 as of January 1, 2019, utilizing the modified prospective approach. For the year ended December 31, 2019, the Company estimates approximately 21% of non-interest income (primarily fees on deposit accounts, other fees and other income) is within the scope of this ASU, with approximately 79% out-of-scope (primarily gains on loan sales, BOLI income, net loan servicing income and letter of credit commissions). Refer to Note 20 - Revenue from Contracts with Customers.

In January 2016, the FASB issued ASU 2016-01, Financial Instruments-Overall: Recognition and Measurement of Financial Assets and Financial Liabilities (Subtopic 825-10). Changes made to the current measurement model primarily affect the accounting for equity securities and readily determinable fair values, where changes in fair value will impact earnings instead of other comprehensive income. The accounting for other financial instruments, such as loans, investments in debt securities, and financial liabilities is largely unchanged. Investments in Federal Home Loan Bank (“FHLB”) and Federal Reserve Bank (“FRB”) stock issued to member financial institutions are not subject to this guidance. Instead, FHLB and FRB stock would continue to be accounted for at cost less impairment under ASC 942-325-35-3. The ASU’s impairment guidance on equity investments for which fair value is not readily determinable also does not apply to FHLB or FRB stock. This Update also changes the presentation and disclosure requirements for financial instruments including a requirement that public business entities use exit price when measuring the fair value of financial instruments measured at amortized cost for disclosure purposes. This Update is generally effective for public business entities in fiscal years beginning after December 15, 2017, including interim periods within those fiscal years and one year later for nonpublic business entities. Based upon an evaluation of the guidance in ASU 2016-01 the Company determined the ASU will not have a material impact on the Company’s consolidated financial statements as the accounting for other financial instruments, such as loans, investments in debt securities, and financial liabilities is largely unchanged. The Company adopted this ASU as of January 1, 2019.

In February 2016, the FASB issued ASU 2016-02, Leases (Topic 842). The most significant change for lessees is the requirement under the new guidance to recognize right-of-use assets and lease liabilities for all leases not considered short-term leases, which is generally defined as a lease term of less than 12 months. This change will result in lessees recognizing right-of-use assets and lease liabilities for most leases currently accounted for as operating leases under current lease accounting guidance. The amendments in this Update are effective for annual periods beginning after December 15, 2020 and for interim periods beginning after December 15, 2021, for an emerging growth company as the effective date was deferred by the FASB. The Company has several lease agreements which are currently considered operating leases and are therefore not included on the Company’s Consolidated Balance Sheets. Under the new guidance the Company expects that some of the lease agreements will have to be recognized on the Consolidated Balance Sheets as a right-of-use asset with a corresponding lease liability. Based upon a preliminary evaluation the Company expects that the ASU will have an impact on the Company’s Consolidated Balance Sheets. The Company will continue to evaluate how extensive the impact will be under the ASU on the Company’s consolidated financial statements. As of this Annual Report and with the Company’s current leases, we estimate the right-of-use asset and lease liability will be in the range of $25-30 million as of the expected January 1, 2023 adoption date. The Company will continue to evaluate how extensive the impact will be under the ASU on the Company’s consolidated financial statements.

In June 2016, the FASB issued ASU 2016-13, Measurement of Credit Losses on Financial Instrument (Topic 326). This ASU significantly changes how entities will measure credit losses for most financial assets and certain other instruments that aren't measured at fair value through net income. The standard will replace today's "incurred loss" approach with an "expected loss" model. The new model, referred to as the current expected credit loss ("CECL") model, will apply to: (1) financial assets subject to credit losses and measured at amortized cost, and (2) certain off-balance sheet credit exposures. This includes, but is not limited to, loans, leases, held to maturity securities, loan commitments, and financial guarantees. For available for sale (“AFS”) debt securities with unrealized losses, entities will measure credit losses in a manner similar to what they do today, except that the losses will be recognized as allowances rather than reductions in the amortized cost of the securities. ASU 2016-13 also expands the disclosure requirements regarding an entity's assumptions, models, and methods for estimating the allowance for loan and lease losses. In addition, public business entities will need to disclose the amortized cost balance for each class of financial asset by credit quality indicator, disaggregated by the year of origination. ASU 2016-13 was originally effective for interim and annual reporting periods for an emerging growth company beginning after December 15, 2020. Entities will apply the standard's provisions as a cumulative-effect adjustment to retained earnings as of the beginning of the first reporting period in which the guidance is effective (i.e., modified retrospective approach). The Company has begun its evaluation of the impact of the implementation of ASU 2016-13. The implementation of the provisions of ASU 2016-13 will most likely impact the Company’s consolidated financial statements as to the level of reserves that will be required for credit losses. The Company will continue to assess the potential impact that this Update will have on the Company’s consolidated financial statements. In October 2019, the FASB announced the delay in the effective date to January 1, 2023 for an EGC. The Company anticipates adopting this ASU 2016-13 on that date.

In January 2017, the FASB issued ASU 2017-04, Intangibles—Goodwill and Other (Topic 350). This Update simplifies how an entity is required to test goodwill for impairment by eliminating Step 2 from the goodwill impairment test. Step 2 measures a goodwill impairment loss by comparing the implied fair value of a reporting unit’s goodwill with the carrying amount of that goodwill. The amendments in this Update are required for public business entities and other entities that have goodwill reported in their financial statements and have not elected the private company alternative for the subsequent measurement of goodwill. As a result, under this Update, “an entity should perform its annual, or interim, goodwill impairment test by comparing the fair value of a reporting unit with its carrying amount and should recognize an impairment charge for the amount by which the carrying amount exceeds the reporting unit’s fair value; however, the loss recognized should not exceed the total amount of goodwill allocated to that reporting unit.” ASU 2017-14 is effective for annual and any interim impairment tests performed in periods beginning after December 15, 2021 for an EGC. Adoption of ASU 2017-04 is not expected to have a significant impact on the Company’s consolidated financial statements.

In June 2018, the FASB issued ASU 2018-07, Compensation—Stock Compensation (Topic 718): Improvements to Nonemployee Share-Based Payment Accounting. The amendments in this Update expand the scope of Topic 718 to include share-based payment transactions for acquiring goods and services from non-employees. An entity should apply the requirements of Topic 718 to non-employee awards except for specific guidance on inputs to an option pricing model and the attribution of cost (that is, the period of time over which share-based payment awards vest and the pattern of cost recognition over that period). The amendments specify that Topic 718 applies to all share-based payment transactions in which a grantor acquires goods or services to be used or consumed in a grantor’s own operations by issuing share-based payment awards. The amendments also clarify that Topic 718 does not apply to share-based payments used to effectively provide (1) financing to the issuer or (2) awards granted in conjunction with selling goods or services to customers as part of a contract accounted for under Topic 606, Revenue from Contracts with Customers. For emerging growth companies, the amendments are effective for fiscal years beginning after December 15, 2019, and interim periods within fiscal years beginning after December 15, 2020. This Update has the potential to only impact share-based payments to the Company’s non-employees. This ASU will not have a material impact on the Company’s consolidated financial statements.

In August 2018, the FASB issued ASU 2018-13, Fair Value Measurement (Topic 820): Disclosure Framework – Changes to the Disclosure Requirements for Fair Value Measurement. The amendments in this Update modify the disclosure requirements on fair value measurements in Topic 820, Fair Value Measurement, based on the concepts in the Concepts Statement, including the consideration of costs and benefits. These disclosure requirements were removed from the topic: (1) The amount of and reasons for transfers between Level 1 and Level 2 of the fair value hierarchy, (2) the policy for timing of transfers between levels, and (3) the valuation processes for Level 3 fair value measurements. These disclosure requirements were modified: (1) For investments in certain entities that calculate net asset value, an entity is required to disclose the timing of liquidation of an investee’s assets and the date when restrictions from redemption might lapse only if the investee has communicated the timing to the entity or announced the timing publicly, and (2) the amendments clarify that the measurement uncertainty disclosure is to communicate information about the uncertainty in measurement as of the reporting date. The following disclosure requirements were added: (1) The changes in unrealized gains and losses for the period included in other comprehensive income for recurring Level 3 fair value measurements held at the end of the reporting period, (2) the range and weighted average of significant unobservable inputs used to develop Level 3 fair value measurements. For certain unobservable inputs, an entity may disclose other quantitative information (such as the median or arithmetic average) in lieu of the weighted average if the entity determines that other quantitative information would be a more reasonable and rational method to reflect the distribution of unobservable inputs used to develop Level 3 fair value measurements. In addition, the amendments eliminate “at a minimum” from the phrase “an entity shall disclose at a minimum to promote the appropriate exercise of discretion by entities when considering fair value measurement disclosures and to clarify that materiality is an appropriate consideration of entities and their auditors when evaluating disclosure requirements”. The amendments in this Update are effective for emerging growth companies for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2019. The amendments on changes in unrealized gains and losses, the range and weighted average of significant unobservable inputs used to develop Level 3 fair value measurements, and the narrative description of measurement uncertainty should be applied prospectively for only the most recent interim or annual period presented in the initial fiscal year of adoption. All other amendments should be applied retrospectively to all periods presented upon their effective date. Early adoption is permitted upon issuance of this Update. An entity is permitted to early adopt any removed or modified disclosures upon issuance of this Update and delay adoption of the additional disclosures until their effective date. As an EGC, RBB adopted this Update on January 1, 2020.

In August 2018, the FASB issued ASU 2018-15, Intangibles—Goodwill and Other—Internal-Use Software (Subtopic 350-40): Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract. This Update provides additional guidance to ASU 2015-05, “Intangibles—Goodwill and Other—Internal-Use Software (Subtopic 350-40): Customer’s Accounting for Fees Paid in a Cloud Computing Arrangement” (CCA), on the accounting for implementation, setup, and other upfront costs (collectively referred to as implementation costs) apply to entities that are a customer in a hosting arrangement. This Update applies to entities that are a customer in a hosting arrangement, which is a service contract. Costs for implementation activities in the application development stage are capitalized depending on the nature of the costs, while costs incurred during the preliminary project and post-implementation stages are expensed as the activities are performed. This Update also require the customer to expense the capitalized implementation costs of a hosting arrangement that is a service contract over the term of the hosting arrangement. This Update is effective for an emerging growth company for annual reporting periods beginning after December 15, 2020, and interim periods within annual periods beginning after December 15, 2021. Early adoption of the amendments in this Update is permitted, including adoption in any interim period, for all entities. The amendments in this Update should be applied either retrospectively or prospectively to all implementation costs incurred after the date of adoption. This Update could be material should RBB incur implementation costs for a CCA that is a service contract.

In November 2019, the FASB issued ASU 2019-08, Compensation—Stock Compensation (Topic 718) and Revenue from Contracts with Customers (Topic 606), Codification Improvements—Share-Based Consideration Payable to a Customer. This ASU will affect companies that issue share-based payments (e.g., options or warrants) to their customers. In June 2018, the FASB issued ASU 2018-07 that expanded the scope of Topic 718, Compensation—Stock Compensation, to include share-based payments to non-employees in exchange for goods and services. That ASU substantially aligned the accounting for share-based payments to non-employees and employees. However, it required share-based payments to nonemployee customers to be accounted for under Topic 606, Revenue from Contracts with Customers, as a reduction of revenue, similar to other sales incentives (such as coupons and rebates). While that ASU provided guidance on the income statement classification of payments to customers (as a reduction of revenue), that ASU did not specify when to measure such awards or how to classify awards on the balance sheet (for example as a liability or as equity). To address diversity in these areas, the new guidance requires companies to measure and classify (on the balance sheet) share-based payments to customers by applying the guidance in Topic 718. As a result, the amount recorded as a reduction in revenue would be measured based on the grant-date fair value of the share-based payment. ASU 2019-08 is effective for entities that have not yet adopted the amendments in ASU 2018-07, the amendments in ASU 2019-08 are effective for an emerging growth company in fiscal years beginning after December 15, 2019, and interim periods within fiscal years beginning after December 15, 2020. Similar to ASU 2018-07, this ASU will not have a material impact on the Company’s financial statements as the Company has not issued share-based payments to non-employees, except for non-employee members of the board of directors.

In November 2019, the FASB issued ASU 2019-10, Financial Instruments—Credit Losses (Topic 326), Derivatives and Hedging (Topic 815), and Leases (Topic 842), Effective Dates. In July 2017, British banking regulators announced plans to eliminate the LIBOR rate by the end of 2021. The purpose of the ASU is to facilitate the effects of reference rate reform on financial reporting. It provides temporary, optional expedients and exceptions related to applying U.S. GAAP to contract modifications, hedging relationships, fair value hedges, and other transactions affected by reference rate reform. The ASU applies only to contracts or hedging relationships that reference LIBOR or another reference rate expected to be discontinued due to reference rate reform. Regulators have established an Alternative Reference Rate Committee to assist with this change. The Company has loans, long-term debt and subordinated debt that have interest rates that reference LIBOR. Of the Company’s $2.3 billion in total gross loans as of December 31, 2019, approximately 25% have a LIBOR based reference rate. The Company has several LIBOR based debt issues, refer to Notes 9 and 10 of the consolidated financial statements. The Company will continue to assess the potential impact that this ASU will have on the Company’s consolidated financial statements.

Acquisitions

12 Months Ended

Dec. 31, 2019

Business Combinations [Abstract]

Acquisitions

NOTE 3 – ACQUISITIONS

First American International Corp. Acquisition:

On October 15, 2018, the Company acquired all the assets and assumed all the liabilities of First American International Corp. in exchange for cash of $34.8 million and 3,011,762 shares of RBB common stocks, which was valued at $69.6 million in the aggregate on the date of acquisition. FAIC operated nine branches in the New York City metropolitan area. The Company acquired FAIC to strategically establish a presence in the New York area. Goodwill in the amount of $28.4 million was recognized in this acquisition. Goodwill represents the future economic benefits arising from net assets acquired that are not individually identified and separately recognized and is attributable to synergies expected to be derived from the combination of the two entities. Goodwill is not deductible for income tax purposes.

The following table represents the assets acquired and liabilities assumed of FAIC as of October 15, 2018 and the fair value adjustments and amounts recorded by the Company in 2018 under the acquisition method of accounting:

	FAIC			Fair Value			Fair
(dollars in thousands)	Book Value			Adjustments			Value
Assets acquired
Cash and cash equivalents	$	55,891		$	—		$	55,891
Fed funds sold		218			—			218
Interest-bearing deposits in other financial Institutions		3,801			—			3,801
Investments - held to maturity		30,814			(611	)		30,203
Investments - available for sale		14,388			—			14,388
Mortgage loans held for sale		1,915			—			1,915
Loans, gross		721,732			(6,161	)		715,571
Allowance for loan losses		(9,583	)		9,583			—
Bank premises and equipment		5,785			3,439			9,224
Mortgage servicing rights		11,274			(660	)		10,614
Core deposit premium		—			6,738			6,738
Other assets		3,518			(2,119	)		1,399
Total assets acquired	$	839,753		$	10,209		$	849,962

Liabilities assumed
Deposits	$	629,609		$	94		$	629,703
FHLB advances		124,500			—			124,500
Subordinated debentures		7,217			(1,241	)		5,976
Other liabilities		14,940			(1,153	)		13,787
Total liabilities assumed		776,266			(2,300	)		773,966
Excess of assets acquired over liabilities assumed		63,487			12,509			75,996
	$	839,753		$	10,209
Stock consideration								69,602
Cash paid								34,837
Goodwill recognized							$	28,443

PGB Holdings Inc. and Pacific Global Bank Acquisition:

On January 10, 2020, we acquired PGB Holdings Inc. and its wholly-owned subsidiary, Pacific Global Bank (“PGB”), in an all-cash transaction for $32.9 million. At the time of acquisition, PGB had approximately $217.6 million in total assets, $192.3 million in total deposits, and three branches in Chicago, Illinois.

Investment Securities

12 Months Ended

Dec. 31, 2019

Investments Debt And Equity Securities [Abstract]

Investment Securities

NOTE 4 - INVESTMENT SECURITIES

The following table summarizes the amortized cost and fair value of available for sale (“AFS”) securities and held to maturity (“HTM”) securities at December 31, 2019 and 2018, and the corresponding amounts of gross unrealized gains and losses recognized in accumulated other comprehensive income:

			Gross		Gross
(dollars in thousands)	Amortized		Unrealized		Unrealized			Fair
December 31, 2019	Cost		Gains		Losses			Value
Available for sale
Government agency securities	$	1,591	$	—	$	(19	)	$	1,572
SBA agency securities		4,671		42		(22	)		4,691
Mortgage-backed securities- Government sponsored agencies		19,126		74		(29	)		19,171
Collateralized mortgage obligations		11,641		38		(25	)		11,654
Corporate debt securities		88,700		281		—			88,981
Total	$	125,729	$	435	$	(95	)	$	126,069

Held to maturity
Municipal taxable securities	$	3,505	$	147	$	—		$	3,652
Municipal securities		4,827		153		—			4,980
Total	$	8,332	$	300	$	—		$	8,632

December 31, 2018
Available for sale
Government agency securities	$	1,873	$	—	$	(58	)	$	1,815
SBA agency securities		5,354		—		(185	)		5,169
Mortgage-backed securities- Government sponsored agencies		23,125		—		(584	)		22,541
Collateralized mortgage obligations		12,696		1		(631	)		12,066
Corporate debt securities		32,615		105		(549	)		32,171
Total	$	75,663	$	106	$	(2,007	)	$	73,762

Held to maturity
Municipal taxable securities	$	4,290	$	142	$	—		$	4,432
Municipal securities		5,671		1		(164	)		5,508
Total	$	9,961	$	143	$	(164	)	$	9,940

During 2019 and 2018 the Company sold $6.1 million and $44.6 million of securities, recognizing gross gains of $7,000 and $5,000, respectively. The Company did not sell any securities in 2017.

One security with a fair value of $627,000 and $697,000 was pledged to secure a local agency deposit at December 31, 2019 and December 31, 2018, respectively.

The amortized cost and fair value of the investment securities portfolio as of December 31, 2019 are shown by expected maturity below. Expected maturities may differ from contractual maturities if borrowers have the right to call or prepay obligations with or without call or prepayment penalties.

	Less than One Year				More than One Year to Five Years				More than Five Years to Ten Years				More than Ten Years				Total
	Amortized		Estimated		Amortized		Estimated		Amortized		Estimated		Amortized		Estimated		Amortized		Estimated
(dollars in thousands)	Cost		Fair Value		Cost		Fair Value		Cost		Fair Value		Cost		Fair Value		Cost		Fair Value
December 31, 2019
Government agency securities	$	—	$	—	$	1,591	$	1,572	$	—	$	—	$	—	$	—	$	1,591	$	1,572
SBA securities		—		—		714		725		3,957		3,966		—		—		4,671		4,691
Mortgage-backed securities- Government sponsored agencies		3,663		3,679		13,027		13,059		2,436		2,433		—		—		19,126		19,171
Collateralized mortgage obligations		—		—		9,288		9,265		2,353		2,389		—		—		11,641		11,654
Corporate debt securities		70,914		70,919		2,002		2,008		11,772		12,024		4,012		4,030		88,700		88,981
Total available for sale	$	74,577	$	74,598	$	26,622	$	26,629	$	20,518	$	20,812	$	4,012	$	4,030	$	125,729	$	126,069

Municipal taxable securities	$	285	$	289	$	2,716	$	2,784	$	504	$	579	$	—	$	—	$	3,505	$	3,652
Municipal securities		—		—		40		40		366		379		4,421		4,561		4,827		4,980
Total held to maturity	$	285	$	289	$	2,756	$	2,824	$	870	$	958	$	4,421	$	4,561	$	8,332	$	8,632

The following table summarizes investment securities with unrealized losses at December 31, 2019 and December 31, 2018, aggregated by major security type and length of time in a continuous unrealized loss position:

	Less than Twelve Months							Twelve Months or More							Total
(dollars in thousands)	Unrealized Losses			Estimated Fair Value		No. of Issuances		Unrealized Losses			Estimated Fair Value		No. of Issuances		Unrealized Losses			Estimated Fair Value		No. of Issuances
December 31, 2019
Government agency securities	$	(19	)	$	1,572		2	$	—		$	—		—	$	(19	)	$	1,572		2
SBA securities		(22	)		1,469		2		—			—		—		(22	)		1,469		2
Mortgage-backed securities- Government sponsored agencies		(5	)		2,631		4		(24	)		3,912		6		(29	)		6,543		10
Collateralized mortgage obligations		(10	)		5,738		3		(15	)		953		2		(25	)		6,691		5
Corporate debt securities		—			—		—		—			—		—		—			—		—
Total available for sale	$	(56	)	$	11,410		11	$	(39	)	$	4,865		8	$	(95	)	$	16,275		19

December 31, 2018
Government agency securities	$	—		$	—		—	$	(58	)	$	1,815		2	$	(58	)	$	1,815		2
SBA securities		—			—		—		(185	)		5,169		4		(185	)		5,169		4
Mortgage-backed securities- Government sponsored agencies		(12	)		1,640		1		(572	)		20,901		23		(584	)		22,541		24
Collateralized mortgage obligations		—			—		—		(631	)		12,065		8		(631	)		12,065		8
Corporate debt securities		(61	)		4,600		4		(488	)		6,548		4		(549	)		11,148		8
Total available for sale	$	(73	)	$	6,240		5	$	(1,934	)	$	46,498		41	$	(2,007	)	$	52,738		46

Municipal securities	$	(104	)	$	2,468		6	$	(60	)	$	2,174		4	$	(164	)	$	4,642		10
Total held to maturity	$	(104	)	$	2,468		6	$	(60	)	$	2,174		4	$	(164	)	$	4,642		10

Unrealized losses have not been recognized into income because the issuer bonds are of high credit quality, management does not intend to sell, it is not more likely than not that management would be required to sell the securities prior to their anticipated recovery and the decline in fair value is largely due to changes in interest rates. The fair value is expected to recover as the bonds approach maturity.

Management evaluates securities for other-than-temporary impairment (“OTTI”) on a quarterly basis, and more frequently when economic or market conditions warrant such an evaluation. For securities in an unrealized loss position, management considers the extent and duration of the unrealized loss, and the financial condition and near-term prospects of the issuer. Management also assesses whether it intends to sell, or it is more likely than not that it will be required to sell, a security in an unrealized loss position before recovery of its amortized cost basis. If either of the criteria regarding intent or requirement to sell is met, the entire difference between amortized cost and fair value is recognized as impairment through earnings.

Loans

12 Months Ended

Dec. 31, 2019

Receivables [Abstract]

Loans

NOTE 5 - LOANS

The Company's loan portfolio consists primarily of loans to borrowers within the Los Angeles, California metropolitan area, the New York City metropolitan area, and Las Vegas, Nevada. Although the Company seeks to avoid concentrations of loans to a single industry or based upon a single class of collateral, real estate and real estate associated businesses are among the principal industries in the Company's market area and, as a result, the Company's loan and collateral portfolios are, to some degree, concentrated in those industries.

A summary of the changes in the allowance for loan losses as of December 31 follows:

(dollars in thousands)	2019			2018			2017
Allowance for loan losses:
Beginning balance	$	17,577		$	13,773		$	14,162
Additions (reductions) to the allowance charged to expense		2,390			4,469			(1,053	)
Recoveries on loans charged-off		108			36			747
Less loans charged-off		(1,259	)		(701	)		(83	)
Ending balance	$	18,816		$	17,577		$	13,773

The following table presents the recorded investment in loans and impairment method as of December 31, 2019, 2018 and 2017 and the activity in the allowance for loan losses for the years then ended, by portfolio segment:

(dollars in thousands)
December 31, 2019	Real Estate			Commercial			Other		Unallocated		Total
Allowance for loan losses:
Beginning of year	$	13,437		$	4,140		$	—	$	—	$	17,577
Provisions		1,847			433			9		101		2,390
Charge-offs		(166	)		(1,093	)		—		—		(1,259	)
Recoveries		—			108			—		—		108
	$	15,118		$	3,588		$	9	$	101	$	18,816
Reserves:
Specific	$	—		$	—		$	—	$	—	$	—
General		15,118			3,588			9		101		18,816
	$	15,118		$	3,588		$	9	$	101	$	18,816
Loans evaluated for impairment:
Individually	$	3,795		$	9,423		$	—	$	—	$	13,218
Collectively		1,842,747			340,148			821		—		2,183,716
	$	1,846,542		$	349,571		$	821	$	—	$	2,196,934

December 31, 2018	Real Estate		Commercial			Unallocated			Total
Allowance for loan losses:
Beginning of year	$	9,309	$	4,044		$	420		$	13,773
Provisions		4,128		761			(420	)		4,469
Charge-offs		—		(701	)		—			(701	)
Recoveries		—		36			—			36
	$	13,437	$	4,140		$	—		$	17,577
Reserves:
Specific	$	—	$	44		$	—		$	44
General		13,393		4,140			—			17,533
Loans acquired with deteriorated credit quality		—		—			—			—
	$	13,437	$	4,140		$	—		$	17,577
Loans evaluated for impairment:
Individually	$	2,309	$	972		$	—		$	3,281
Collectively		1,750,896		387,838			—			2,138,734
Loans acquired with deteriorated credit quality		—		—			—			—
	$	1,753,205	$	388,810		$	—		$	2,142,015

December 31, 2017	Real Estate		Commercial			Unallocated			Total
Allowance for loan losses:
Beginning of year	$	8,111	$	6,051		$	—		$	14,162
Provisions		1,198		(2,671	)		420			(1,053	)
Charge-offs		—		(83	)		—			(83	)
Recoveries		—		747			—			747
	$	9,309	$	4,044		$	420		$	13,773
Reserves:
Specific	$	—	$	—		$	—		$	—
General		9,309		4,044			420			13,773
Loans acquired with deteriorated credit quality		—		—			—			—
	$	9,309	$	4,044		$	420		$	13,773
Loans evaluated for impairment:
Individually	$	2,420	$	155		$	—		$	2,575
Collectively		834,152		412,032			—			1,246,184
Loans acquired with deteriorated credit quality		315		—			—			315
	$	836,887	$	412,187		$	—		$	1,249,074

The Company categorizes loans into risk categories based on relevant information about the ability of borrowers to service their debt such as current financial information, historical payment experience, collateral adequacy, credit documentation, and current economic trends, among other factors. The Company analyzes loans individually by classifying the loans as to credit risk. This analysis typically includes larger, non-homogeneous loans such as commercial real estate and commercial and industrial loans. This analysis is performed on an ongoing basis as new information is obtained. The Company uses the following definitions for risk ratings:

Pass - Loans classified as pass include loans not meeting the risk ratings defined below.

Special Mention - Loans classified as special mention have a potential weakness that deserves management's close attention. If left uncorrected, these potential weaknesses may result in deterioration of the repayment prospects for the loan or of the institution's credit position at some future date.

Substandard - Loans classified as substandard are inadequately protected by the current net worth and paying capacity of the obligor or of the collateral pledged, if any. Loans so classified have a well-defined weakness or weaknesses that jeopardize the liquidation of the debt. They are characterized by the distinct possibility that the institution will sustain some loss if the deficiencies are not corrected.

Impaired - A loan is considered impaired, when, based on current information and events, it is probable that the Company will be unable to collect all amounts due according to the contractual terms of the loan agreement. Additionally, all loans classified as troubled debt restructurings are considered impaired.

The risk category of loans by class of loans was as follows as of December 31, 2019 and 2018:

(dollars in thousands)			Special
December 31, 2019	Pass		Mention		Substandard		Impaired		Total
Real estate:
Construction and land development	$	95,756	$	—	$	—	$	264	$	96,020
Commercial real estate		767,603		5,353		18,115		2,197		793,268
Single-family residential mortgages		955,327		—		593		1,334		957,254
Commercial:
Commercial and industrial		265,178		4,078		5,330		—		274,586
SBA		61,496		189		3,877		9,423		74,985
Other:		821		—		—		—		821
	$	2,146,181	$	9,620	$	27,915	$	13,218	$	2,196,934

December 31, 2018
Real estate:
Construction and land development	$	112,959	$	—	$	—	$	276	$	113,235
Commercial real estate		743,123		7,069		6,496		2,033		758,721
Single-family residential mortgages		880,860		—		389		—		881,249
Commercial:
Commercial and industrial		295,226		6,286		2,798		—		304,310
SBA		79,057		—		4,471		972		84,500
	$	2,111,225	$	13,355	$	14,154	$	3,281	$	2,142,015

The following table presents the aging of the recorded investment in past-due loans as of December 31, 2019 and 2018 by class of loans:

(dollars in thousands)	30-59		60-89		90 Days		Total		Loans Not				Non- Accrual
December 31, 2019	Days		Days		Or More		Past Due		Past Due		Total Loans		Loans ⁽¹⁾
Real estate:
Construction and land development	$	—	$	—	$	—	$	—	$	96,020	$	96,020	$	—
Commercial real estate		—		—		725		725		792,543		793,268		725
Single-family residential mortgages		1,454		1,560		450		3,464		953,790		957,254		1,334
Commercial:
Commercial and industrial		—		—		—		—		274,586		274,586		—
SBA		2,263		—		9,378		11,641		63,344		74,985		9,378
Other:		—		—		—		—		821		821		—
	$	3,717	$	1,560	$	10,553	$	15,830	$	2,181,104	$	2,196,934	$	11,437
Real estate:
Single-family residential mortgages held for sale	$	—	$	—	$	—	$	—	$	108,194	$	108,194	$	—

December 31, 2018
Real estate:
Construction and land development	$	—	$	—	$	—	$	—	$	113,235	$	113,235	$	—
Commercial real estate		—		678		—		678		758,043		758,721		—
Single-family residential mortgages		1,548		950		—		2,498		878,751		881,249		—
Commercial:
Commercial and industrial		—		—		—		—		304,310		304,310		—
SBA		957		—		914		1,871		82,629		84,500		914
	$	2,505	$	1,628	$	914	$	5,047	$	2,136,968	$	2,142,015	$	914
Real estate:
Single-family residential mortgages held for sale	$	—	$	458	$	—	$	458	$	434,064	$	434,522	$	—

(1)	Included in total loans

Information relating to individually impaired loans presented by class of loans was as follows as of December 31, 2019, 2018 and 2017:

	Unpaid
(dollars in thousands)	Principal		Recorded		Average		Interest		Related
December 31, 2019	Balance		Investment		Balance		Income		Allowance
With no related allowance recorded
Construction and land development	$	264	$	264	$	271	$	24	$	—
Commercial real estate		2,198		2,197		2,384		100		—
Residential mortgage loans		1,349		1,334		1,351		—		—
Commercial - SBA		9,423		9,423		10,791		4		—
With related allowance recorded
Commercial-SBA		—		—		—		—		—
Total	$	13,234	$	13,218	$	14,797	$	128	$	—

December 31, 2018
With no related allowance recorded
Construction and land development	$	276	$	276	$	283	$	23	$	—
Commercial real estate		2,033		2,033		2,126		134		—
Commercial - SBA		797		1,498		1,377		19		—
With related allowance recorded
Commercial-SBA		175		175		193		1		44
Total	$	3,281	$	3,982	$	3,979	$	177	$	44
December 31, 2017
With no related allowance recorded
Construction and land development	$	289	$	289	$	296	$	16	$	—
Commercial real estate		2,131		2,131		2,192		297		—
Commercial - SBA		155		155		78		15		—
Total	$	2,575	$	2,575	$	2,566	$	328	$	—

No interest income was recognized on a cash basis as of December 31, 2019, 2018 and 2017. We did not recognize any interest income on nonaccrual loans during the years ended December 31, 2019 and December 31, 2018 while the loans were in nonaccrual status. We recognized interest income on loans modified under troubled debt restructurings ("TDR's") of $128,000 and $177,000 during the years ended December 31, 2019 and December 31, 2018, respectively.

The Company had four loans identified as troubled debt restructurings at December 31, 2019 and 2018, respectively. There were no specific reserves allocated to the loans as of December 31, 2019 and 2018. There were no commitments to lend additional amounts as of December 31, 2019 and 2018, respectively, to customers with outstanding loans that are classified as TDR's.

During the year ended December 31, 2019, the terms of certain loans were modified as TDR's. The modification of the terms generally included loans where a moratorium on loan payments was granted. Such moratoriums ranged from three months to six months on the loans restructured in 2019.

The following table presents loans by class modified as TDR's that occurred during the year ended December 31, 2019:

Pre-

Post-

Modification

(dollars in thousands)

Number of

Recorded

December 31, 2019

Loans

Investment

Commercial real estate

476

There were no defaults of TDR’s in 2019 and 2018 where the loan was modified within the prior twelve months.

In the past the Company has purchased loans as part of its whole bank acquisitions, for which there was at acquisition, evidence of deterioration of credit quality since origination and it was probable, at acquisition, that all contractually required payments would not be collected. The purchased credit-impaired loan fully paid off in September 2018. There were no balances as of December 31, 2019 and 2018.

Below is a summary of activity in the accretable yield on purchased credit-impaired loans for 2019, 2018 and 2017:

(dollars in thousands)	2019		2018			2017
Beginning balance	$	—	$	7		$	142
Disposals		—		—			—
Restructuring as TDR		—		—			—
Accretion of income		—		(7	)		(135	)
Ending balance	$	—	$	—		$	7

Loan Servicing

12 Months Ended

Dec. 31, 2019

Loan Servicing [Abstract]

Loan Servicing

NOTE 6 - LOAN SERVICING

Mortgage and SBA loans serviced for others are not reported as assets. The principal balances as of December 31, 2019 and 2018 are as follows:

(dollars in thousands)	2019		2018
Loans serviced for others:
Mortgage loans	$	1,683,298	$	1,586,499
SBA loans		170,849		184,664
Commercial real estate loans		4,216		2,838

Activity for servicing assets follows:

	2019						2018						2017
	Mortgage			SBA			Mortgage			SBA			Mortgage			SBA
(dollars in thousands)	Loans			Loans			Loans			Loans			Loans			Loans
Servicing assets:
Beginning of period	$	12,858		$	4,512		$	1,540		$	4,417		$	1,002		$	2,702
Acquisitions		—			—			10,651			—			—			—
Additions		2,088			980			1,562			1,932			1,115			2,628
Disposals		(128	)		(708	)		(197	)		(1,177	)		(172	)		(367	)
Amortized to expense		(1,821	)		(698	)		(698	)		(660	)		(405	)		(546	)
End of period	$	12,997		$	4,086		$	12,858		$	4,512		$	1,540		$	4,417

The fair value of servicing assets for mortgage loans was $15.1 million and $15.3 million as of December 31, 2019 and 2018, respectively. Fair value at December 31, 2019 was determined using a discount rate of 10.82%, prepayment speeds ranging from 7.27% to 20.15%, depending on the stratification of the specific right, and a weighted-average default rate of 0.11%. Fair value at December 31, 2018 was determined using a discount rate of 10.59%, prepayment speeds ranging from 8.26% to 16.82%, depending on the stratification of the specific right, and a weighted-average default rate of 0.20%.

The fair value of servicing assets for SBA loans was $5.6 million and $6.1 million as of December 31, 2019 and 2018, respectively. Fair value at December 31, 2019 was determined using a discount rate of 8.50%, prepayment speeds ranging from 12.50% to 14.66%, depending on the stratification of the specific right, and a weighted-average default rate of 0.43%. Fair value at December 31, 2018 was determined using a discount rate of 8.50% and prepayment speeds ranging from 11.43% to 12.11%, depending on the stratification of the specific right and a weighted-average default rate of 0.52%.

Servicing fees net of servicing asset amortization totaled $3.4 million, $850,000, and $722,000 for the years ended December 31, 2019, 2018, and 2017, respectively.

Premises and Equipment

12 Months Ended

Dec. 31, 2019

Property Plant And Equipment [Abstract]

Premises and Equipment

NOTE 7 - PREMISES AND EQUIPMENT

A summary of premises and equipment as of December 31 follows:

(dollars in thousands)	2019			2018
Land	$	5,020		$	5,020
Building and improvements		7,822			7,823
Furniture, fixtures, and equipment		6,252			4,833
Leasehold improvements		5,590			4,845
		24,684			22,521
Less accumulated depreciation and amortization		(8,102	)		(6,312	)
Construction in progress		231			1,098
	$	16,813		$	17,307

Depreciation and leasehold amortization expense was $1.8 million, $989,000, and $686,000 for 2019, 2018, and 2017, respectively.

The Company leases several of its operating facilities under various noncancellable operating leases expiring at various dates through 2028. The Company is also responsible for common area maintenance, taxes and insurance at the various branch locations.

Future minimum rent payments on the Company's leases were as follows as of December 31, 2019:

(dollars in thousands)
Year ending December 31:
2020	$	5,603
2021		4,634
2022		4,192
2023		3,250
2024		2,209
Thereafter		8,998
	$	28,886

The minimum rent payments shown above are given for the existing lease obligations and are not a forecast of future rental expense. Total rental expense, recognized on a straight-line basis, was $6.1 million, $2.7 million, and $1.5 million for 2019, 2018, and 2017, respectively.

The lease for the Company’s downtown headquarters expired in May 2018. In October 2018 the Company signed a lease for a new headquarters office at 1055 Wilshire Boulevard, Suite 1220, Los Angeles, California 90017, which the Company occupied in November 2018. In February 2018 the Company signed a lease for a new office in Irvine, California which the Company occupied in October 2018. In September 2017 the Company signed a lease to occupy a new location in Oxnard, California which the Company occupied in March 2018. In October 2018 the Company signed a lease to occupy a new location in Flushing, New York which the Company occupied in February 2019. In January 2020, the Company signed a lease to for a new branch in Edison, New Jersey, which the Company expects to occupy in June 2020. In March 2020, the Company signed a new lease to its Diamond Bar, California branch to a new location. The future payments for all of the new leases are included in the schedule above. The Company recorded $197,000 in sub-lease income in 2019.

Deposits

12 Months Ended

Dec. 31, 2019

Maturities Of Time Deposits [Abstract]

Deposits

NOTE 8 - DEPOSITS

At December 31, 2019 the scheduled maturities of time deposits are as follows:

(dollars in thousands)
One year	$	1,215,913
Two to three years		34,863
Over three years		1,909
Total	$	1,252,685

Brokered time deposits were $67.1 million at December 31, 2019 and $113.8 million at December 31, 2018.

Long-term Debt

12 Months Ended

Dec. 31, 2019

Debt Disclosure [Abstract]

Long-term Debt

NOTE 9 - LONG-TERM DEBT

At December 31, 2019 and 2018, respectively, long-term debt was as follows:

(dollars in thousands)	2019		2018
Principal	$	105,000	$	105,000
Unamortized debt issuance costs	$	951	$	1,292

In March 2016, the Company issued $50 million of 6.5% fixed to floating rate subordinated debentures, due March 31, 2026. The interest rate is fixed through March 31, 2021 and floats at 3 month LIBOR plus 516 basis points thereafter. The Company can redeem these subordinated debentures beginning March 31, 2021. The sub-debt is considered Tier-two capital at the Company. The Company allocated $35 million to the Bank as Tier-one capital.

In November 2018, the Company issued $55 million of 6.18% fixed to floating rate subordinated debentures, due December 1, 2028. The interest rate is fixed through December 1, 2023 and floats at 3 month LIBOR plus 315 basis points thereafter. The Company can redeem these subordinated debentures beginning December 1, 2023. The sub-debt is considered Tier-two capital at the Company. The Company allocated $25 million to the Bank as Tier-one capital.

The following table presents interest and amortization expense the Company incurred for the year ended December 31, 2019 and 2018:

	For the Year Ended December 31,
(dollars in thousands)	2019		2018
Interest Expense:
Interest	$	6,649	$	3,552
Amortization		342		162

Subordinated Debentures

12 Months Ended

Dec. 31, 2019

Debt Instruments [Abstract]

Subordinated Debentures

NOTE 10 - SUBORDINATED DEBENTURES

The Company, through the acquisition of TFC Bancorp in 2016, acquired TFC Statutory Trust (the “Trust”). The Trust contained a pooled private offering of 5,000 trust preferred securities with a liquidation amount of $1,000 per security. TFC Bancorp issued $5 million of subordinated debentures to the Trust in exchange for ownership of all of the common security of the Trust and the proceeds of the preferred securities sold by the trust. The Company is not considered the primary beneficiary of this trust (variable interest entity), therefore the Trust is not consolidated in the Company's financial statements, but rather the subordinated debentures are shown as a liability at market value as of the close of the acquisition which was $3.3 million. There was a $1.9 million valuation reserve recorded to arrive at market value, which is treated as a yield adjustment and is amortized over the life of the security. The Company also purchased an investment in the common stock of the trust for $155,000, which is included in other assets. The Company may redeem the subordinated debentures, subject to prior approval by the Board of Governors of the Federal Reserve System on or after March 15, 2012, at 100% of the principal amount, plus accrued and unpaid interest. The subordinated debentures mature on March 15, 2037. The Company has the option to defer interest payments on the subordinated debentures from time to time for a period not to exceed five consecutive years. The Company has been paying interest on a quarterly basis. The subordinated debentures may be included in Tier I capital (with certain limitations applicable) under current regulatory guidelines and interpretations. The subordinated debentures have a variable rate of interest equal to the three month London Interbank Offered Rate (LIBOR) plus 1.65%, which was 3.54% as of December 31, 2019 and 4.66% at December 31, 2018.

In October 2018, the Company, through the acquisition of First American International Corp., acquired First American International Statutory Trust I (“FAIC Trust”), a Delaware statutory trust formed in December 2004. The Trust issued 7,000 units of thirty-year fixed to floating rate capital securities with an aggregate liquidation amount of $7 million to an independent investor, and FAIC issued $7 million of subordinated debentures to the FAIC Trust and all of its common securities, amounting to $217,000, which is included in other assets. There was a $1.2 million valuation reserve recorded to arrive at market value which is treated as a yield adjustment and is amortized over the life of the security. The Company has the option to defer interest payments on the subordinated debentures from time to time for a period not to exceed five consecutive years. The subordinated debenture have a variable rate of interest equal to the three-month LIBOR plus 2.25% through final maturity on December 15, 2034. The rate at December 31, 2019, was 4.14% and 5.04% at December 31, 2018.

The Company paid interest expenses of $540,000 in 2019, $263,000 in 2018 and $144,000 in 2017. The amount of aggregate amortization expense recognized in 2019 was $167,000, in 2018 was $106,000 and $90,000 in 2017.

For regulatory reporting purposes, the Federal Reserve Board has indicated that the capital securities qualify as Tier I capital of the Company subject to previously specified limitations, until further notice. If regulators make a determination that the capital securities can no longer be considered in regulatory capital, the securities become callable and the Company may redeem them.

In July 2017, British banking regulators announced plans to eliminate the LIBOR rate by the end of 2021, before these subordinated notes and debentures mature. For these subordinated notes and debentures, there are provisions for amendments to establish a new interest rate benchmark.

Borrowing Arrangements

12 Months Ended

Dec. 31, 2019

Debt Disclosure [Abstract]

Borrowing Arrangements

NOTE 11 - BORROWING ARRANGEMENTS

The Company has established secured and unsecured lines of credit. The Company may borrow funds from time to time on a term or overnight basis from the Federal Home Loan Bank of San Francisco ("FHLB"), the Federal Reserve Bank of San Francisco ("FRB") and other financial institutions as indicated below.

Federal Funds Arrangements with Commercial Banks. As of December 31, 2019 the Company may borrow on an unsecured basis, up to $20.0 million, $10.0 million, $12.0 million and $5.0 million overnight from Zions Bank, Wells Fargo Bank, First Tennessee National Bank, and Pacific Coast Bankers' Bank, respectively.

Letter of Credit Arrangements. As of December 31, 2019 the Company had an unsecured commercial letter of credit line with Wells Fargo Bank for $2.0 million.

FRB Secured Line of Credit. The secured borrowing capacity with the FRB of $14.3 million at December 31, 2019 is collateralized by loans pledged with a carrying value of $28.7 million.

FHLB Secured Line of Credit. The secured borrowing capacity with the FHLB of $636.5 million at December 31, 2019 is collateralized by loans pledged with a carrying value of $727.8 million.

At December 31, 2019, the Company had no overnight advances with the FHLB and $319.5 million at 2.56% at December 31, 2018. There were no amounts outstanding under any of the other borrowing arrangements above as of December 31, 2019 and at December 31, 2018 except FHLB advances.

Income Taxes

12 Months Ended

Dec. 31, 2019

Income Tax Disclosure [Abstract]

Income Taxes

NOTE 12 - INCOME TAXES

The asset and liability method is used in accounting for income taxes. Under this method, deferred tax assets and liabilities are determined based on differences between financial reporting and tax bases of assets and liabilities and are measured using the enacted tax rates and laws that will be in effect when the differences are expected to reverse.

Income tax expense consists of the following:

(dollars in thousands)	2019		2018			2017
Current:
Federal	$	8,074	$	6,616		$	12,097
State		5,614		3,451			3,773
		13,688		10,067			15,870
Deferred		1,503		(131	)		2,492
Deferred tax adjustment for change in tax rate		21		(479	)		2,591
Amortization of investment in affordable housing tax credits		900		644			316
	$	16,112	$	10,101		$	21,269

A comparison of the federal statutory income tax rates to the Company's effective income tax rates as of December 31 follows:

	2019						2018						2017
(dollars in thousands)	Amount			Rate			Amount			Rate			Amount			Rate
Statutory federal tax	$	11,617			21.0	%	$	9,703		21.0%			$	16,379			35.0	%
State franchise tax, net of federal benefit		5,322			9.6	%		3,488		7.5%				3,135			6.7	%
Tax-exempt income		(25	)		0.0	%		(27	)	-0.1%				(297	)		-0.6	%
Tax impact from change in tax rate		17			0.0	%		(479	)	-1.0%				2,591			5.5	%
Stock-based compensation		(27	)		0.0	%		(2,643	)	-5.7%				—			0.0	%
Other items, net		(792	)		-1.4	%		59		0.1%				(539	)		-1.2	%
Actual tax expense	$	16,112			29.2	%	$	10,101			21.8	%	$	21,269			45.4	%

Deferred taxes are a result of differences between income tax accounting and generally accepted accounting principles with respect to income and expense recognition. The following is a summary of the components of the net deferred tax asset accounts recognized in the accompanying balance sheets as of December 31:

(dollars in thousands)	2019			2018
Deferred tax assets:
Pre-opening expenses	$	122		$	154
Allowance for loan losses		5,883			5,545
Stock-based compensation		1,346			1,419
Off balance sheet reserve		258			217
Operating loss carryforwards		1,253			1,688
Other real estate owned		37			10
Unrealized loss on AFS securities		—			600
Mark to market on held for sale mortgage loans		359			2,451
Other		1,594			1,220
		10,852			13,304
Deferred tax liabilities:
Depreciation		(282	)		(521	)
Unrealized gain on AFS securities		(106	)		—
Acquisition accounting fair value adjustments		(2,671	)		(2,067	)
Mortgage servicing rights		(3,745	)		(3,586	)
Other		(1,722	)		(2,488	)
		(8,526	)		(8,662	)
Net deferred tax assets	$	2,326		$	4,642

At December 31, 2019, the Company has net operating loss carryforwards from acquisitions of approximately $32,000 for federal, zero for California, $9.6 million for New York State and $8.8 million for New York City income tax purposes. Net operating loss carry forwards, to the extent not used will begin to expire in 2028. Net operating loss carryforwards available from acquisitions are substantially limited by Section 382 of the Internal Revenue Code and benefits not expected to be realized due to the limitation have been excluded from the deferred tax asset and net operating loss carryforward amounts noted above. The Company acquired operating loss carryforwards in its acquisitions that were subject to limitations under Section 382 of the Internal Revenue Code. The amount of net operating loss carry forwards subject to the 382 limitations amounts to $3.8 million, $11.4 million, $12.3 million and $9.3 million for federal, California, New York State and New York City income tax purposes, respectively.

The Company is subject to federal income tax and franchise tax of the state of California and New York. Income tax returns for the years ended after December 31, 2015 are open to audit by the federal and New York authorities and for the years ended after December 31, 2014 are open to audit by California state authorities.

There were no recorded interest or penalties related to uncertain tax positions as part of income tax for the years ended December 31, 2019, 2018, and 2017, respectively. The Company has determined that as of December 31, 2019 all tax positions taken to date are highly certain and, accordingly, no accounting adjustment has been made to the consolidated financial statements.

Commitments

12 Months Ended

Dec. 31, 2019

Commitments And Contingencies Disclosure [Abstract]

Commitments

NOTE 13 - COMMITMENTS

In the ordinary course of business, the Company enters into financial commitments to meet the financing needs of its customers. These financial commitments include commitments to extend credit, unused lines of credit, commercial and similar letters of credit and standby letters of credit. Those instruments involve to varying degrees, elements of credit and interest rate risk not recognized in the Company's financial statements.

The Company's exposure to loan loss in the event of nonperformance on these financial commitments is represented by the contractual amount of those instruments. The Company uses the same credit policies in making commitments as it does for loans reflected in the financial statements.

As of December 31, 2019 and 2018, the Company had the following financial commitments whose contractual amount represents credit risk:

	2019				2018
	Fixed		Variable		Fixed		Variable
(dollars in thousands)	Rate		Rate		Rate		Rate
Commitments to make loans	$	—	$	167,496	$	5,211	$	125,610
Unused lines of credit		55,789		102,841		61,191		75,908
Commercial and similar letters of credit		—		358		1,042		—
Standby letters of credit		2,485		1,230		2,701		673
	$	58,274	$	271,925	$	70,145	$	202,191

Commitments to extend credit are agreements to lend to a customer as long as there is no violation of any condition established in the contract. Since many of the commitments are expected to expire without being drawn upon, the total amounts do not necessarily represent future cash requirements. The Company evaluates each client's credit worthiness on a case-by-case basis. The amount of collateral obtained if deemed necessary by the Company is based on management's credit evaluation of the customer.

The Company is involved in various matters of litigation which have arisen in the ordinary course of business and accruals for estimates of potential losses have been provided when necessary and appropriate under generally accepted accounting principles. In the opinion of management, the disposition of such pending litigation will not have a material effect on the Company's financial statements.

Related Party Transactions

12 Months Ended

Dec. 31, 2019

Related Party Transactions

NOTE 14 - RELATED PARTY TRANSACTIONS

Loans to principal officers, directors, and their affiliates were as follows:

(dollars in thousands)	2019			2018
Beginning balance	$	3,600		$	2,300
New loans and advances		16,180			7,400
Repayments		(15,780	)	$	(6,100	)
Ending balance	$	4,000		$	3,600

There were no loan commitments outstanding to executive officers, directors and their related interests with whom they are associated as of December 31, 2019 and $800,000 as of December 31, 2018.

Deposits from principal officers, directors, and their affiliates at year-end 2019 and 2018 were $84.6 million and $52.1 million.

Stock Option Plan

12 Months Ended

Dec. 31, 2019

Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]

Stock Option Plan

NOTE 15- STOCK OPTION PLAN

Under the terms of the Company's 2017 Omnibus Stock Incentive Plan, officers and key employees may be granted both nonqualified and incentive stock options and directors and organizers, who are not also an officer or employee, may only be granted nonqualified stock options. The Plan provides for options to purchase up to 30 percent of the outstanding common stock at a price not less than 100 percent of the fair market value of the stock on the date of the grant. Stock options expire no later than ten years from the date of the grant and generally vest over three years.

At December 31, 2019, 1,254,045 shares were available under the 2017 Omnibus Stock Incentive Plan for future grants.

The Company recognized stock-based compensation expense of $689,000, $684,000, and $779,000 in 2019, 2018, and 2017 and recognized income tax benefits on that expense of $161,000, $202,000, and $246,000, respectively.

The Company did not grant restricted stock awards in 2019. The Company granted restricted stock awards for 43,425 shares at a closing price of $29.38 in 2018. There were no restricted stock grants in prior years. These restricted stock units are scheduled to vest over a three year period from the August 15, 2018 grant date. During the year ended 2019, 14,475 restricted stock units vested. As of December 31, 2019, there were 28,950 remaining unvested restricted stock units. As of December 31, 2019 there was $691,000 of total unamortized restricted stock compensation and weighted average grant price was $29.38. The intrinsic value of vested restricted was $262,000 as of December 31, 2019.

The fair value of each option grant was estimated on the date of grant using the Black-Scholes option pricing model with the following weighted-average assumptions presented below for 2019 and 2016. There were no stock options granted in 2018 and 2017.

	2019			2016
Expected volatility		35.0	%		35.0	%
Expected term	6.0 years			6.0 years
Expected dividends		1.90	%	None
Risk free rate		2.66	%		1.93	%
Grant date fair value	$	6.32		$	6.76

Since the Company had a limited amount of historical stock activity, the expected volatility was based on the historical volatility of similar banks that had a longer trading history. The expected term represents the estimated average period of time that the options remain outstanding. The expected term of options granted is based on historical data and represents the period of time that options granted are expected to be outstanding. The risk free rate of return reflects the grant date interest rate offered for zero coupon U.S. Treasury bonds over the expected term of the options.

A summary of the status of the Company's stock option plan as of December 31, 2019 and changes during the year then ended is presented below:

						Weighted-
				Weighted-		Average
				Average		Remaining	Aggregate
				Exercise		Contractual	Intrinsic
(dollars in thousands, except for share amounts)	Shares			Price		Term	Value
Outstanding at beginning of year		1,215,097		$	12.83
Granted		76,500			18.38
Exercised		(200,629	)		13.43
Outstanding at end of year		1,090,968		$	13.11	4.07 years	$	8,790
Options exercisable		1,014,468		$	12.72	3.69 years	$	8,577

As of December 31, 2019 there was approximately $332,000 of total unrecognized compensation cost related to outstanding stock options that will be recognized over a weighted-average period of 2 years. The intrinsic value of options exercised was $1.2 million, $13.6 million, and $2.8 million in 2019, 2018, and 2017, respectively.

The total fair value of the shares vested was $460,000, $734,000, and $930,000 in 2019, 2018, and 2017, respectively. The number of unvested stock options were 76,500, 62,008 and 163,996 with a weighted average grant date fair value of $6.32, $6.48 and $6.53 as of December 31, 2019, 2018 and 2017.

Cash received from the exercise of 200,629 share options was $2.8 million for the period ended December 31, 2019.

Regulatory Matters

12 Months Ended

Dec. 31, 2019

Banking And Thrift [Abstract]

Regulatory Matters

NOTE 16 - REGULATORY MATTERS

Holding companies (with assets over $3 billion at the beginning of the year) and banks are subject to various regulatory capital requirements administered by the federal banking agencies. Failure to meet minimum capital requirements can initiate certain mandatory - and possibly additional discretionary - actions by regulators that, if undertaken, could have a direct material effect on the Company's financial statements.

In July, 2013, the federal bank regulatory agencies approved the final rules implementing the Basel Committee on Banking Supervision's capital guidelines for U.S. banks. The new rules became effective on January 1, 2015, with certain of the requirements phased-in over a multi-year schedule. Under the rules, minimum requirements increased for both the quantity and quality of capital held by the Bank. The rules include a new common equity Tier 1 ("CET1") capital to risk-weighted assets ratio with minimums for capital adequacy and prompt corrective action purposes of 4.5% and 6.5%, respectively. The minimum Tier 1 capital to risk-weighted assets ratio was raised from 4.0% to 6.0% under the capital adequacy framework and from 6.0% to 8.0% to be well-capitalized under the prompt corrective action framework. In addition, the rules introduced the concept of a "conservation buffer" of 2.5% applicable to the three capital adequacy risk-weighted asset ratios (CET1, Tier 1, and Total). The implementation of the capital conservation buffer began on January 1, 2016 at 0.625% and will be phased in over a four-year period (increasing by that amount on each subsequent January 1, until it reaches 2.5% on January 1, 2019). If the capital adequacy minimum ratios plus the phased-in conservation buffer amount exceed actual risk-weighted capital ratios, then dividends, share buybacks, and discretionary bonuses to executives could be limited in amount.

Under capital adequacy guidelines and the regulatory framework for prompt corrective action, the Bank must meet specific capital guidelines that involve quantitative measures of the Bank's assets, liabilities, and certain off-balance-sheet items as calculated under regulatory accounting practices. Capital amounts and classification are also subject to qualitative judgments by the regulators about components, risk weightings, and other factors. Quantitative measures established by regulation to ensure capital adequacy require the Bank to maintain minimum amounts and ratios (set forth in the table below) of total, Tier 1 and CET1 capital (as defined in the regulations) to risk-weighted assets (as defined), and of Tier 1 capital (as defined) to average assets (as defined). As permitted by the regulators for financial institutions that are not deemed to be “advanced approaches” institutions, the Company has elected to opt out of the Basel III requirement to include accumulated other comprehensive income in risk-based capital. Management believes, at December 31, 2019 and December 31, 2018, that the Bank satisfied all capital adequacy requirements to which it is subject.

The capital conservation buffer is being phased in for 0.0% for 2015 to 2.50% by 2019. The net unrealized gain or loss on available for sale securities is not included in computing regulatory capital. Management believes, as of December 31, 2019 and 2018, that the Bank meets all capital adequacy requirements to which it is subject.

As of December 31, 2019 and 2018, the most recent notification from the FDIC categorized the Bank as well-capitalized under the regulatory framework for prompt corrective action (there are no conditions or events since that notification that management believes have changed the Bank's category). To be categorized as well-capitalized, the Bank must maintain minimum ratios as set forth in the table below.

The following table sets forth RBB Bancorp's consolidated and the Bank's actual capital amounts and ratios and related regulatory requirements for the Bank as of December 31, 2019:

						Amount of Capital Required
											To Be Well-Capitalized
						Minimum Required for					Under Prompt Corrective
	Actual					Capital Adequacy Purposes					Provisions
(dollars in thousands)	Amount		Ratio			Amount		Ratio			Amount		Ratio
As of December 31, 2019:
Tier 1 Leverage Ratio
Consolidated	$	353,572		12.89	%	NA		NA			NA		NA
Bank		417,036		15.23	%	$	108,150		4.0	%	$	135,187		5.0	%
Common Equity Tier 1 Risk-Based Capital Ratio
Consolidated	$	343,899		17.16	%	NA		NA			NA		NA
Bank		417,036		20.87	%		89,127		4.5	%		128,739		6.5	%
Tier 1 Risk-Based Capital Ratio
Consolidated	$	353,572		17.65	%	NA		NA			NA		NA
Bank		417,036		20.87	%		118,836		6.0	%		158,448		8.0	%
Total Risk-Based Capital Ratio
Consolidated	$	477,262		23.82	%	NA		NA			NA		NA
Bank		436,677		21.86	%		158,448		8.0	%		198,061		10.0	%

The following table sets forth RBB Bancorp's consolidated and the Bank's actual capital amounts and ratios and related regulatory requirements for the Bank as of December 31, 2018:

						Amount of Capital Required
											To Be Well-Capitalized
						Minimum Required for					Under Prompt Corrective
	Actual					Capital Adequacy Purposes					Provisions
(dollars in thousands)	Amount		Ratio			Amount		Ratio			Amount		Ratio
As of December 31, 2018:
Tier 1 Leverage Ratio
Consolidated	$	321,407		11.80	%	NA		NA			NA		NA
Bank		370,304		13.66	%	$	108,445		4.0	%	$	135,556		5.0	%
Common Equity Tier 1 Risk Based Capital Ratio
Consolidated	$	311,901		15.28	%	NA		NA			NA		NA
Bank		370,304		18.17	%	$	91,722		4.5	%	$	132,487		6.5	%
Tier 1 Risk-Based Capital Ratio
Consolidated	$	321,407		15.74	%	NA		NA			NA		NA
Bank		370,304		18.17	%		122,296		6.0	%	$	163,061		8.0	%
Total Risk-Based Capital Ratio
Consolidated	$	443,379		21.71	%	NA		NA			NA		NA
Bank		388,569		19.07	%	$	163,061		8.0	%	$	203,826		10.0	%

The California Financial Code generally acts to prohibit banks from making a cash distribution to its shareholders in excess of the lesser of the bank's undivided profits or the bank's net income for its last three fiscal years less the amount of any distribution made by the bank's shareholders during the same period.

The California general corporation law generally acts to prohibit companies from paying dividends on common stock unless its retained earnings, immediately prior to the dividend payment, equals or exceeds the amount of the dividend. If a company fails this test, then it may still pay dividends if after giving effect to the dividend the company's assets are at least 125% of its liabilities.

Additionally, the Federal Reserve Bank has issued guidance which requires that they be consulted before payment of a dividend if a bank holding company does not have earnings over the prior four quarters of at least equal to the dividend to be paid, plus other holding company obligations.

- Definition

The entire disclosure for regulatory capital requirement for depository and lending institutions. Institutions include, but not are not limited to, finance company, insured depository institution, bank holding company, savings and loan association holding company, bank and savings institution not federally insured, mortgage company, foreign financial institution and credit union.

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+ Details

Fair Value Measurements

12 Months Ended

Dec. 31, 2019

Fair Value Disclosures [Abstract]

Fair Value Measurements

NOTE 17 - FAIR VALUE MEASUREMENTS

The following is a description of valuation methodologies used for assets and liabilities recorded at fair value:

Securities: The fair values of securities available for sale are determined by obtaining quoted prices on nationally recognized securities exchanges (Level 1) or matrix pricing, which is a mathematical technique used widely in the industry to value debt securities without relying exclusively on quoted prices for specific securities but rather by relying on the securities' relationship to other benchmark quoted securities (Level 2).

Other Real Estate Owned: Nonrecurring adjustments to certain commercial and residential real estate properties classified as other real estate owned are measured at the lower of carrying amount or fair value, less costs to sell. In cases where the carrying amount exceeds the fair value, less costs to sell, an impairment loss is recognized. Fair values are generally based on third party appraisals of the property which are commonly adjusted by management to reflect an expectation of the amount to be ultimately collected and selling costs (Level 3).

Appraisals for other real estate owned are performed by state licensed appraisers (for commercial properties) or state certified appraisers (for residential properties) whose qualifications and licenses have been reviewed and verified by the Company. When a Notice of Default is recorded, an appraisal report is ordered. Once received, a member of the credit administration department reviews the assumptions and approaches utilized in the appraisal as well as the overall resulting fair value in comparison to independent data sources such as recent market data or industry wide-statistics for residential appraisals. Commercial appraisals are sent to an independent third party to review. The Company also compares the actual selling price of collateral that has been sold to the most recent appraised value to determine what additional adjustments, if any, should be made to the appraisal values on any remaining other real estate owned to arrive at fair value. If the existing appraisal is older than twelve months a new appraisal report is ordered. No significant adjustments to appraised values have been made as a result of this comparison process as of December 31, 2019.

Collateral-dependent impaired loans: Collateral-dependent impaired loans are carried at fair value when it is probable that the Company will be unable to collect all amounts due according to the contractual terms of the original loan agreement and the loan has been written down to the fair value of its underlying collateral, net of expected disposition costs where applicable.

The following table provides the hierarchy and fair value for each major category of assets and liabilities measured at fair value at December 31, 2019 and 2018:

(dollars in thousands)	Fair Value Measurements Using:
December 31, 2019	Level 1		Level 2		Level 3		Total
Assets measured at fair value:
On a recurring basis:
Securities available for sale
Government agency securities	$	—	$	1,572	$	—	$	1,572
SBA agency securities		—		4,691		—		4,691
Mortgage-backed securities		—		19,171		—		19,171
Collateralized mortgage obligations		—		11,654		—		11,654
Commercial paper		—		69,898				69,898
Corporate debt securities		—		19,083		—		19,083
	$	—	$	126,069	$	—	$	126,069
On a non-recurring basis:
Other real estate owned		—		—		293		293
	$	—	$	—	$	293	$	293

December 31, 2018	Level 1		Level 2		Level 3		Total
Assets measured at fair value:
On a recurring basis:
Securities available for sale
Government agency securities	$	—	$	1,815	$	—	$	1,815
SBA agency securities		—		5,169		—		5,169
Mortgage-backed securities		—		22,541		—		22,541
Collateralized mortgage obligations		—		12,066		—		12,066
Commercial paper		—		14,918				14,918
Corporate debt securities		—		17,253		—		17,253
	$	—	$	73,762	$	—	$	73,762
On a non-recurring basis:
Commercial real estate - collateral dependent impaired loans	$	—		—	$	123	$	123
Other real estate owned		—		—	$	1,101	$	1,101
	$	—	$	—	$	1,224	$	1,224

No write-downs to OREO were recorded in 2019 or 2018.

Quantitative information about the Company's non-recurring Level 3 fair value measurements as of December 31, 2019 and 2018 is as follows:

Weighted-

(dollars in thousands)

Fair Value

Valuation

Unobservable

Adjustment

Average

December 31, 2019

Amount

Technique

Input

Range

Adjustment

Other real estate owned

293

Third Party

Management Adjustments

29%

Appraisals

to Reflect Current

Conditions and Selling

Costs

December 31, 2018

Other real estate owned

1,101

Third Party

Management Adjustments

16%

Appraisals

to Reflect Current

Conditions and Selling

Costs

Fair Value of Financial Instruments

12 Months Ended

Dec. 31, 2019

Fair Value Disclosures [Abstract]

Fair Value of Financial Instruments

NOTE 18 - FAIR VALUE OF FINANCIAL INSTRUMENTS

The fair value of a financial instrument is the amount at which the asset or obligation could be exchanged in a current transaction between willing parties, other than in a forced or liquidation sale. Fair value estimates are made at a specific point in time based on relevant market information and information about the financial instrument. These estimates do not reflect any premium or discount that could result from offering for sale at one time the entire holdings of a particular financial instrument. Because no market value exists for a significant portion of the financial instruments, fair value estimates are based on judgments regarding future expected loss experience, current economic conditions, risk characteristics of various financial instruments, and other factors. These estimates are subjective in nature, involve uncertainties and matters of judgment and, therefore, cannot be determined with precision. Changes in assumptions could significantly affect the estimates.

Fair value estimates are based on financial instruments both on and off the balance sheet without attempting to estimate the value of anticipated future business and the value of assets and liabilities that are not considered financial instruments. Additionally, tax consequences related to the realization of the unrealized gains and losses can have a potential effect on fair value estimates and have not been considered in many of the estimates.

The following methods and assumptions were used to estimate the fair value of significant financial instruments not previously presented:

Cash and Cash Equivalents

The carrying amounts of cash and short-term instruments approximate fair values.

Time Deposits in Other Banks

Fair values for time deposits with other banks are estimated using discounted cash flow analyses, using interest rates currently being offered with similar terms.

Loans

For variable rate loans that reprice frequently and with no significant change in credit risk, fair values are based on carrying amounts. The fair values for all other loans are estimated using discounted cash flow analyses, using interest rates currently being offered for loans with similar terms to borrowers with similar credit quality. In accordance with the prospective adoption of ASU 2016-01, the fair value of loans as of December 31, 2019 was measured using an exit price notion. The fair value of loans as of December 31, 2018 was measured using an exit price notion.

Mortgage Loans Held for Sale

The Company records mortgage loans held for sale at fair value based on the net premium received on recent sales of mortgage loans for identical pools of loans.

Deposits

The fair values disclosed for demand deposits, including interest and non-interest demand accounts, savings, and certain types of money market accounts are, by definition based on carrying value. Fair value for fixed-rate certificates of deposit is estimated using a discounted cash flow calculation that applies interest rates currently being offered on certificates to a schedule of aggregate expected monthly maturities on time deposits. Early withdrawal of fixed-rate certificates of deposit is not expected to be significant

FHLB Advances

The carrying amounts of short-term debt with maturities of less than ninety days, such as FHLB Advances, approximate their fair values.

Long-Term Debt

The fair values of the Company’s long-term borrowings are estimated using discounted cash flow analyses based on the current borrowing rates for similar types of borrowing arrangements resulting in a Level 2 classification.

Subordinated Debentures

The fair values of the Company’s Subordinated Debentures are estimated using discounted cash flow analyses based on the current borrowing rates for similar types of borrowing arrangements resulting in a Level 3 classification.

Off-Balance Sheet Financial Instruments

The fair value of commitments to extend credit and standby letters of credit is estimated using the fees currently charged to enter into similar agreements. The fair value of these financial instruments is not material.

The fair value hierarchy level and estimated fair value of significant financial instruments at December 31, 2019 and 2018 are summarized as follows:

		2019				2018
	Fair Value	Carrying		Fair		Carrying		Fair
(dollars in thousands)	Hierarchy	Value		Value		Value		Value
Financial Assets:
Cash and due from banks	Level 1	$	114,763	$	114,763	$	147,685	$	147,685
Federal funds sold and other cash equivalents	Level 1		67,000		67,000		—		—
Interest-earning deposits in other financial institutions	Level 1		600		600		600		600
Investment securities - AFS	Level 2		126,069		126,069		73,762		73,762
Investment securities - HTM	Level 2		8,332		8,632		9,961		9,940
Mortgage loans held for sale	Level 1		108,194		109,385		434,522		438,948
Loans, net	Level 3		2,178,118		2,158,970		2,124,438		2,114,341
Equity securities	Level 3		11,826		11,826		10,039		10,039
Mortgage servicing rights	Level 2		17,083		20,752		17,370		21,361

Financial Liabilities:
Deposits	Level 2	$	2,248,938	$	2,236,329	$	2,144,041	$	2,143,196
FHLB advances	Level 2		—		—		319,500		319,500
Long-term debt	Level 2		104,049		109,877		103,708		79,756
Subordinated debentures	Level 3		9,673		11,709		9,506		10,356

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References + Details

Earnings Per Share ("EPS")

12 Months Ended

Dec. 31, 2019

Earnings Per Share [Abstract]

Earnings Per Share ("EPS")

NOTE 19 - EARNINGS PER SHARE ("EPS")

The following is a reconciliation of net income and shares outstanding to the income and number of shares used to compute EPS:

	2019						2018					2017
(dollars in thousands except per share amounts)	Income			Shares			Income		Shares			Income		Shares
Net income as reported	$	39,209					$	36,105				$	25,528
Less: Earnings allocated to Participating Securities		(74	)					—					—
Shares outstanding					20,030,866					20,000,022					15,908,893
Impact of weighting shares					(13,560	)				(2,848,800	)				(1,830,612	)
Used in basic EPS		39,135			20,017,306			36,105		17,151,222			25,528		14,078,281
Dilutive effect of outstanding
Stock options					376,118					816,431					1,160,084
Used in dilutive EPS	$	39,135			20,393,424		$	36,105		17,967,653		$	25,528		15,238,365

Basic earnings per common share	$	1.96					$	2.11				$	1.81
Diluted earnings per common share		1.92						2.01					1.68

Stock options for 76,500 shares and 399,000 shares of common stock were not considered in computing diluted earnings per common share for Dec 31, 2019 and 2018, respectively because they were anti-dilutive. There were no anti-dilutive stock options in December 31, 2017.

Revenue From Contracts With Customers

12 Months Ended

Dec. 31, 2019

Revenue From Contract With Customer [Abstract]

Revenue From Contracts With Customers

NOTE 20 – REVENUE FROM CONTRACTS WITH CUSTOMERS

On January 1, 2019, the Company adopted ASU 2014-09, Revenue from Contracts with Customers - Topic 606 and all subsequent ASUs that modified ASC 606. The Company adopted ASC 606 using the modified retrospective method applied to those contracts that were not completed as of January 1, 2019. The new standard did not materially impact the timing or measurement of the Company’s revenue recognition as it is consistent with the Company’s existing accounting for contracts within the scope of the new standard. There was no cumulative effect adjustment to retained earnings as a result of adopting this new standard.

The following is a summary of revenue from contracts with customers that are in-scope and not in-scope under Topic 606:

	For the Year Ended December 31,
(dollars in thousands)	2019			2018		2017
Non-interest income, in scope ⁽¹⁾
Fees and service charges on deposit accounts	$	1,366		$	1,115	$	1,164
Other fees ⁽²⁾		1,118			723		145
Other income ⁽³⁾		1,429			709		501
(Loss) gain on sale of OREO and fixed assets		(100	)		—		142
Total in-scope non-interest income		3,813			2,547		1,952
Non-interest income, not in scope ⁽⁴⁾		14,507			10,295		11,249
Total non-interest income	$	18,320		$	12,842	$	13,201

(1)	There were no adjustments to the Company's financial statements recorded as a result of the adoption of ASC 606.

(2)	Other fees consists of wealth management fees, miscellaneous loan fees and postage/courier fees.

(3)	Other income consists of safe deposit box rental income, wire transfer fees, security brokerage fees, annuity sales, insurance activity, and OREO income.

(4)

The amounts primarily represent revenue from contracts with customers that are out of scope of ASC606: Net loan servicing income, letter of credit commissions, import/export commissions, recoveries on purchased loans, BOLI income, and gains (losses) on sales of mortgage loans, loans and investment securities.

The major revenue streams by fee type that are within the scope of ASC 606 presented in the above tables are described in additional detail below:

Fees and Services Charges on Deposit Accounts

Fees and service charges on deposit accounts include charges for analysis, overdraft, cash checking, ATM, and safe deposit activities executed by our deposit clients, as well as interchange income earned through card payment networks for the acceptance of card based transactions. Fees earned from our deposit clients are governed by contracts that provide for overall custody and access to deposited funds and other related services, and can be terminated at will by either party; this includes fees from money service businesses (MSBs). Fees received from deposit clients for the various deposit activities are recognized as revenue once the performance obligations are met. Periodic service charges are generally collected monthly directly from the customer’s deposit account, and at the end of a statement cycle, while transaction based service charges are typically collected at the time of or soon after the service is performed. The adoption of ASU 2014-09 had no impact to the recognition of fees and service charges on deposit accounts.

Wealth Management Fees

The Company employs financial consultants to provide investment planning services for customers including wealth management services, asset allocation strategies, portfolio analysis and monitoring, investment strategies, and risk management strategies. The commission fees the Company earns are variable and are generally received monthly. The Company recognizes revenue for the services performed at quarter-end based on actual transaction details received from the broker dealer the Company engages.

In the Company’s wealth management division, revenue is primarily generated from (1) securities brokerage accounts, (2) investment advisor accounts, (3) full service brokerage implementation fees, and (4) life insurance and annuity products.

Gain on Sales of Other Real Estate Owned and Fixed Assets

The Company records a gain or loss from the sale of OREO and fixed assets, when control of the property or asset transfers to the buyer, which generally occurs at the time of an executed deed or sales agreement. When the Company finances the sale of OREO to a buyer, the Company assesses whether the buyer is committed to perform their obligations under the contract and whether collectability of the transaction price is probable. Once these criteria are met, the OREO asset is derecognized and the gain or loss on sale is recorded upon transfer of control of the property to the buyer. In determining the gain or loss on the sale, the Company adjusts the transaction price and related gain or loss on sale if a significant financing component is present.

Qualified Affordable Housing Project Investments

12 Months Ended

Dec. 31, 2019

Text Block [Abstract]

Qualified Affordable Housing Project Investments

NOTE 21 – QUALIFIED AFFORDABLE HOUSING PROJECT INVESTMENTS

The Company began investing in qualified affordable housing projects in 2016. At December 31, 2019 and December 31, 2018, the balance of the investment for qualified affordable housing projects was $8.6 million and $9.5 million, respectively. This balance is reflected in the accrued interest and other assets line on the consolidated balance sheets. Total unfunded commitments related to the investments in qualified affordable housing projects totaled $4.2 million and $6.8 million at December 31, 2019 and December 31, 2018. The Company expects to fulfill these commitments between 2020 and 2027.

During the years ending December 31, 2019, 2018 and 2017, the Company recognized amortization expense of $900,000, $644,000 and $316,000, respectively, which was included within income tax expense on the consolidated statements of income.

During the years ended December 31, 2019, 2018 and 2017, the Company recognized tax credits from its investment in affordable housing tax credits of $1.1 million, $573,000 and $275,000, respectively. The Company had no impairment losses during the years ended December 31, 2019, 2018 and 2017

Parent Only Condensed Financial Information

12 Months Ended

Dec. 31, 2019

Condensed Financial Information Of Parent Company Only Disclosure [Abstract]

Parent Only Condensed Financial Information

NOTE 22 - PARENT ONLY CONDENSED FINANCIAL INFORMATION

The parent company only condensed statements of financial condition as of December 31, 2019 and 2018, and the related condensed statements of income and condensed statements of cash flows for the years ended December 31, 2019, 2018, and 2017 are presented below:

Condensed Statements of Financial Condition

(Dollars in Thousands)	2019		2018
ASSETS
Cash and cash equivalents	$	29,985	$	45,540
Investment in Bank		480,703		433,023
Investment in RAM		6,870		6,796
Other assets		4,202		2,820
Total assets	$	521,760	$	488,179

LIABILITIES AND SHAREHOLDERS' EQUITY
Long term debt		104,049		103,708
Subordinated debentures		9,673		9,506
Other liabilities		348		344
Total liabilities		114,070		113,558
Shareholders' equity:
Common stock		290,395		288,610
Additional paid-in capital		4,938		5,659
Retained earnings		112,046		81,618
Non-controlling interest		72		72
Accumulated other comprehensive income (loss)		239		(1,338	)
Total shareholders' equity		407,690		374,621
Total liabilities and shareholders' equity	$	521,760	$	488,179

Condensed Statements of Income

(Dollars in Thousands)	2019			2018			2017
Interest income	$	—		$	15		$	—
Interest expense		7,697			4,083			3,629
Noninterest expense		1,300			1,255			642
Loss before equity in undistributed income of subsidiaries		(8,997	)		(5,323	)		(4,271	)
Equity in undistributed income of:
Bank		45,324			39,198			27,620
RAM		74			528			143
Income before income taxes		36,401			34,403			23,492
Income tax benefit		2,808			1,702			2,036
Net income		39,209			36,105			25,528
Other comprehensive income (loss)		1,577			(895	)		(104	)
Total comprehensive income	$	40,786		$	35,210		$	25,424

Condensed Statements of Cash Flows

(Dollars in Thousands)	2019			2018			2017
Cash flows from operating activities:
Net income	$	39,209		$	36,105		$	25,528
Net amortization of other		508			268			235
Provision for deferred income taxes		513			(1,905	)		1,807
Undistributed income of subsidiaries		(45,398	)		(39,726	)		(27,763	)
Change in other assets and liabilities		(1,981	)		3,492			(3,923	)
		(7,149	)		(1,766	)		(4,116	)
Cash flows from investment activities:
Net cash acquired (outlay) in connection with acquisition		—			(41,358	)		—
Investment in subsidiaries		—			(15,000	)		(25,000	)
		—			(56,358	)		(25,000	)
Cash flows from financing activities:
Issuance of subordinated debentures, net of issuance costs		—			54,018			—
Issuance of common stock, net of issuance costs		—			—			60,210
Dividends paid		(8,033	)		(5,753	)		(5,118	)
Common stock repurchased, net of repurchased costs		(3,190	)
Stock options exercised		2,817			9,630			2,296
		(8,406	)		57,895			57,388

Increase in cash and cash equivalents		(15,555	)		(229	)		28,272
Cash and cash equivalents beginning of year		45,540			45,769			17,497
Cash and cash equivalents end of year	$	29,985		$	45,540		$	45,769

Subsequent Events

12 Months Ended

Dec. 31, 2019

Subsequent Events [Abstract]

Subsequent Events

NOTE 23 – SUBSEQUENT EVENTS

On January 10, 2020, we acquired PGB Holdings Inc. and its wholly-owned subsidiary, Pacific Global Bank (“PGB”) in an all-cash transaction for $32.9 million. At the time of acquisition, PGB had approximately $217.6 million in total assets, $192.3 million in total deposits, and three branches in Chicago, Illinois. The fair value accounting process has not been completed for this acquisition.

Quarterly Income Statements (Unaudited)

12 Months Ended

Dec. 31, 2019

Quarterly Financial Information Disclosure [Abstract]

Quarterly Income Statements (Unaudited)

NOTE 24 – QUARTERLY INCOME STATEMENTS (Unaudited)

The following table presents the unaudited quarterly condensed income statements for the years 2019 and 2018.

	2019								2018
(dollars in thousands)	4th Quarter		3rd Quarter		2nd Quarter		1st Quarter		4th Quarter		3rd Quarter		2nd Quarter		1st Quarter
Interest income	$	33,907	$	34,669	$	35,943	$	37,206	$	35,181	$	24,473	$	22,284	$	20,177
Interest expense		10,784		11,157		11,626		11,294		9,599		5,857		4,457		3,732
Net interest income		23,123		23,512		24,317		25,912		25,582		18,616		17,827		16,445
Provision for credit losses		659		824		357		550		1,890		1,695		700		184
Net interest income after provision for credit losses		22,464		22,688		23,960		25,362		23,692		16,921		17,127		16,261
Noninterest income:		5,823		2,799		5,496		4,202		5,489		2,105		2,793		2,455
Noninterest expense:		13,463		13,786		14,899		15,325		15,503		8,654		8,191		8,289
Income before income taxes		14,824		11,701		14,557		14,239		13,678		10,372		11,729		10,427
Income tax expense		4,149		3,689		4,415		3,859		4,188		2,041		2,292		1,580
Net income	$	10,675	$	8,012	$	10,142	$	10,380	$	9,490	$	8,331	$	9,437	$	8,847

Net income per share
Basic	$	0.53	$	0.40	$	0.51	$	0.52	$	0.48	$	0.50	$	0.58	$	0.55
Diluted		0.52		0.39		0.50		0.51		0.47		0.48		0.54		0.52

Repurchase of Common Stock

12 Months Ended

Dec. 31, 2019

Equity [Abstract]

Repurchase of Common Stock

NOTE 25 – REPURCHASE OF COMMON STOCK

During 2019 the board of directors approved the Company to repurchase up to 1,000,000 million shares of stock. As of December 31, 2019 the Company had repurchased 169,785 shares of stock at an average per share price of $18.79.

Basis of Presentation and Summary of Significant Accounting Policies (Policies)

12 Months Ended

Dec. 31, 2019

Accounting Policies [Abstract]

Basis of Presentation

Principles of Consolidation and Nature of Operations

RBB Bancorp has no significant business activity other than its investments in Royal Business Bank and RAM. Parent only condensed financial information on RBB Bancorp is provided in Note 22.

Use of Estimates in the Preparation of Financial Statements

Cash and Cash Equivalents

Cash and Due From Banks

Cash and Due from Banks

Interest-Bearing Deposits in Other Financial Institutions

Interest-bearing deposits in other financial institutions not included in cash and cash equivalents are carried at cost and generally mature in one year or less.

Investment Securities

Loans Held For Sale

Loans

Allowance for Loan Losses

Certain Acquired Loans

Servicing Rights

Transfer of Financial Assets

Transfers of Financial Assets

Premises and Equipment

Other Real Estate Owned

Goodwill and Other Intangible Assets

Estimated CDI amortization expense for the next 5 years is as follows (dollars in thousands):

(dollars in thousands)
Year ending December 31:
2020	$	1,285
2021		1,056
2022		879
2023		749
2024		638
Thereafter		1,493
Total	$	6,100

Bank Owned Life Insurance

FHLB Stock and Other Equity Securities

As of December 31, 2019 the Company had several CRA equity investments without readily determinable fair values in the amount of $11.8 million, and $10.0 million at December 31, 2018.

Stock-Based Compensation

Income Taxes

Retirement Plans

The Company established a 401(k) plan in 2010. The Company contributed $570,000, $341,000, and $272,000 in 2019, 2018 and 2017, respectively.

Comprehensive Income

Comprehensive income consists of net income and other comprehensive income. Other comprehensive income includes unrealized gains and losses on securities available for sale.

Financial Instruments

Earnings Per Share ("EPS")

Fair Value Measurement

Level 1: Quoted prices (unadjusted) for identical assets or liabilities in active markets that the entity has the ability to access as of the measurement date.

Level 3: Significant unobservable inputs that reflect the Company's own assumptions about the assumptions that market participants would use in pricing an asset or liability.

See Note 17 and Note 18 for more information and disclosures relating to the Company's fair value measurements.

Operating Segments

Recent Accounting Pronouncements

Basis of Presentation and Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2019

Accounting Policies [Abstract]

Schedule of Future Estimated Amortization Expense

Estimated CDI amortization expense for the next 5 years is as follows (dollars in thousands):

(dollars in thousands)
Year ending December 31:
2020	$	1,285
2021		1,056
2022		879
2023		749
2024		638
Thereafter		1,493
Total	$	6,100

Acquisitions (Tables)

12 Months Ended

Dec. 31, 2019

First American International Corp.

Schedule of Assets Acquired and Liabilities Assumed and Fair Value Adjustments

	FAIC			Fair Value			Fair
(dollars in thousands)	Book Value			Adjustments			Value
Assets acquired
Cash and cash equivalents	$	55,891		$	—		$	55,891
Fed funds sold		218			—			218
Interest-bearing deposits in other financial Institutions		3,801			—			3,801
Investments - held to maturity		30,814			(611	)		30,203
Investments - available for sale		14,388			—			14,388
Mortgage loans held for sale		1,915			—			1,915
Loans, gross		721,732			(6,161	)		715,571
Allowance for loan losses		(9,583	)		9,583			—
Bank premises and equipment		5,785			3,439			9,224
Mortgage servicing rights		11,274			(660	)		10,614
Core deposit premium		—			6,738			6,738
Other assets		3,518			(2,119	)		1,399
Total assets acquired	$	839,753		$	10,209		$	849,962

Liabilities assumed
Deposits	$	629,609		$	94		$	629,703
FHLB advances		124,500			—			124,500
Subordinated debentures		7,217			(1,241	)		5,976
Other liabilities		14,940			(1,153	)		13,787
Total liabilities assumed		776,266			(2,300	)		773,966
Excess of assets acquired over liabilities assumed		63,487			12,509			75,996
	$	839,753		$	10,209
Stock consideration								69,602
Cash paid								34,837
Goodwill recognized							$	28,443

Investment Securities (Tables)

12 Months Ended

Dec. 31, 2019

Investments Debt And Equity Securities [Abstract]

Summary of Amortized Cost and Fair Value of Available for Sale Securities and Held to Maturity Securities

			Gross		Gross
(dollars in thousands)	Amortized		Unrealized		Unrealized			Fair
December 31, 2019	Cost		Gains		Losses			Value
Available for sale
Government agency securities	$	1,591	$	—	$	(19	)	$	1,572
SBA agency securities		4,671		42		(22	)		4,691
Mortgage-backed securities- Government sponsored agencies		19,126		74		(29	)		19,171
Collateralized mortgage obligations		11,641		38		(25	)		11,654
Corporate debt securities		88,700		281		—			88,981
Total	$	125,729	$	435	$	(95	)	$	126,069

Held to maturity
Municipal taxable securities	$	3,505	$	147	$	—		$	3,652
Municipal securities		4,827		153		—			4,980
Total	$	8,332	$	300	$	—		$	8,632

December 31, 2018
Available for sale
Government agency securities	$	1,873	$	—	$	(58	)	$	1,815
SBA agency securities		5,354		—		(185	)		5,169
Mortgage-backed securities- Government sponsored agencies		23,125		—		(584	)		22,541
Collateralized mortgage obligations		12,696		1		(631	)		12,066
Corporate debt securities		32,615		105		(549	)		32,171
Total	$	75,663	$	106	$	(2,007	)	$	73,762

Held to maturity
Municipal taxable securities	$	4,290	$	142	$	—		$	4,432
Municipal securities		5,671		1		(164	)		5,508
Total	$	9,961	$	143	$	(164	)	$	9,940

Amortized Cost and Fair Value of Investment Securities Portfolio Expected Maturity

	Less than One Year				More than One Year to Five Years				More than Five Years to Ten Years				More than Ten Years				Total
	Amortized		Estimated		Amortized		Estimated		Amortized		Estimated		Amortized		Estimated		Amortized		Estimated
(dollars in thousands)	Cost		Fair Value		Cost		Fair Value		Cost		Fair Value		Cost		Fair Value		Cost		Fair Value
December 31, 2019
Government agency securities	$	—	$	—	$	1,591	$	1,572	$	—	$	—	$	—	$	—	$	1,591	$	1,572
SBA securities		—		—		714		725		3,957		3,966		—		—		4,671		4,691
Mortgage-backed securities- Government sponsored agencies		3,663		3,679		13,027		13,059		2,436		2,433		—		—		19,126		19,171
Collateralized mortgage obligations		—		—		9,288		9,265		2,353		2,389		—		—		11,641		11,654
Corporate debt securities		70,914		70,919		2,002		2,008		11,772		12,024		4,012		4,030		88,700		88,981
Total available for sale	$	74,577	$	74,598	$	26,622	$	26,629	$	20,518	$	20,812	$	4,012	$	4,030	$	125,729	$	126,069

Municipal taxable securities	$	285	$	289	$	2,716	$	2,784	$	504	$	579	$	—	$	—	$	3,505	$	3,652
Municipal securities		—		—		40		40		366		379		4,421		4,561		4,827		4,980
Total held to maturity	$	285	$	289	$	2,756	$	2,824	$	870	$	958	$	4,421	$	4,561	$	8,332	$	8,632

Summary of Investment Securities With Unrealized Losses

	Less than Twelve Months							Twelve Months or More							Total
(dollars in thousands)	Unrealized Losses			Estimated Fair Value		No. of Issuances		Unrealized Losses			Estimated Fair Value		No. of Issuances		Unrealized Losses			Estimated Fair Value		No. of Issuances
December 31, 2019
Government agency securities	$	(19	)	$	1,572		2	$	—		$	—		—	$	(19	)	$	1,572		2
SBA securities		(22	)		1,469		2		—			—		—		(22	)		1,469		2
Mortgage-backed securities- Government sponsored agencies		(5	)		2,631		4		(24	)		3,912		6		(29	)		6,543		10
Collateralized mortgage obligations		(10	)		5,738		3		(15	)		953		2		(25	)		6,691		5
Corporate debt securities		—			—		—		—			—		—		—			—		—
Total available for sale	$	(56	)	$	11,410		11	$	(39	)	$	4,865		8	$	(95	)	$	16,275		19

December 31, 2018
Government agency securities	$	—		$	—		—	$	(58	)	$	1,815		2	$	(58	)	$	1,815		2
SBA securities		—			—		—		(185	)		5,169		4		(185	)		5,169		4
Mortgage-backed securities- Government sponsored agencies		(12	)		1,640		1		(572	)		20,901		23		(584	)		22,541		24
Collateralized mortgage obligations		—			—		—		(631	)		12,065		8		(631	)		12,065		8
Corporate debt securities		(61	)		4,600		4		(488	)		6,548		4		(549	)		11,148		8
Total available for sale	$	(73	)	$	6,240		5	$	(1,934	)	$	46,498		41	$	(2,007	)	$	52,738		46

Municipal securities	$	(104	)	$	2,468		6	$	(60	)	$	2,174		4	$	(164	)	$	4,642		10
Total held to maturity	$	(104	)	$	2,468		6	$	(60	)	$	2,174		4	$	(164	)	$	4,642		10

Loans (Tables)

12 Months Ended

Dec. 31, 2019

Receivables [Abstract]

Summary of Balance and Activity Related to Allowance for Loan Losses for Held for Investment Loans and the Recorded Investments in Loans and Impairment method by Portfolio Segment

A summary of the changes in the allowance for loan losses as of December 31 follows:

(dollars in thousands)	2019			2018			2017
Allowance for loan losses:
Beginning balance	$	17,577		$	13,773		$	14,162
Additions (reductions) to the allowance charged to expense		2,390			4,469			(1,053	)
Recoveries on loans charged-off		108			36			747
Less loans charged-off		(1,259	)		(701	)		(83	)
Ending balance	$	18,816		$	17,577		$	13,773

(dollars in thousands)
December 31, 2019	Real Estate			Commercial			Other		Unallocated		Total
Allowance for loan losses:
Beginning of year	$	13,437		$	4,140		$	—	$	—	$	17,577
Provisions		1,847			433			9		101		2,390
Charge-offs		(166	)		(1,093	)		—		—		(1,259	)
Recoveries		—			108			—		—		108
	$	15,118		$	3,588		$	9	$	101	$	18,816
Reserves:
Specific	$	—		$	—		$	—	$	—	$	—
General		15,118			3,588			9		101		18,816
	$	15,118		$	3,588		$	9	$	101	$	18,816
Loans evaluated for impairment:
Individually	$	3,795		$	9,423		$	—	$	—	$	13,218
Collectively		1,842,747			340,148			821		—		2,183,716
	$	1,846,542		$	349,571		$	821	$	—	$	2,196,934

December 31, 2018	Real Estate		Commercial			Unallocated			Total
Allowance for loan losses:
Beginning of year	$	9,309	$	4,044		$	420		$	13,773
Provisions		4,128		761			(420	)		4,469
Charge-offs		—		(701	)		—			(701	)
Recoveries		—		36			—			36
	$	13,437	$	4,140		$	—		$	17,577
Reserves:
Specific	$	—	$	44		$	—		$	44
General		13,393		4,140			—			17,533
Loans acquired with deteriorated credit quality		—		—			—			—
	$	13,437	$	4,140		$	—		$	17,577
Loans evaluated for impairment:
Individually	$	2,309	$	972		$	—		$	3,281
Collectively		1,750,896		387,838			—			2,138,734
Loans acquired with deteriorated credit quality		—		—			—			—
	$	1,753,205	$	388,810		$	—		$	2,142,015

December 31, 2017	Real Estate		Commercial			Unallocated			Total
Allowance for loan losses:
Beginning of year	$	8,111	$	6,051		$	—		$	14,162
Provisions		1,198		(2,671	)		420			(1,053	)
Charge-offs		—		(83	)		—			(83	)
Recoveries		—		747			—			747
	$	9,309	$	4,044		$	420		$	13,773
Reserves:
Specific	$	—	$	—		$	—		$	—
General		9,309		4,044			420			13,773
Loans acquired with deteriorated credit quality		—		—			—			—
	$	9,309	$	4,044		$	420		$	13,773
Loans evaluated for impairment:
Individually	$	2,420	$	155		$	—		$	2,575
Collectively		834,152		412,032			—			1,246,184
Loans acquired with deteriorated credit quality		315		—			—			315
	$	836,887	$	412,187		$	—		$	1,249,074

Summary of Risk Category of Loans by Class of Loans

The risk category of loans by class of loans was as follows as of December 31, 2019 and 2018:

(dollars in thousands)			Special
December 31, 2019	Pass		Mention		Substandard		Impaired		Total
Real estate:
Construction and land development	$	95,756	$	—	$	—	$	264	$	96,020
Commercial real estate		767,603		5,353		18,115		2,197		793,268
Single-family residential mortgages		955,327		—		593		1,334		957,254
Commercial:
Commercial and industrial		265,178		4,078		5,330		—		274,586
SBA		61,496		189		3,877		9,423		74,985
Other:		821		—		—		—		821
	$	2,146,181	$	9,620	$	27,915	$	13,218	$	2,196,934

December 31, 2018
Real estate:
Construction and land development	$	112,959	$	—	$	—	$	276	$	113,235
Commercial real estate		743,123		7,069		6,496		2,033		758,721
Single-family residential mortgages		880,860		—		389		—		881,249
Commercial:
Commercial and industrial		295,226		6,286		2,798		—		304,310
SBA		79,057		—		4,471		972		84,500
	$	2,111,225	$	13,355	$	14,154	$	3,281	$	2,142,015

Summary of Aging Recorded Investment Past-due Loans

The following table presents the aging of the recorded investment in past-due loans as of December 31, 2019 and 2018 by class of loans:

(dollars in thousands)	30-59		60-89		90 Days		Total		Loans Not				Non- Accrual
December 31, 2019	Days		Days		Or More		Past Due		Past Due		Total Loans		Loans ⁽¹⁾
Real estate:
Construction and land development	$	—	$	—	$	—	$	—	$	96,020	$	96,020	$	—
Commercial real estate		—		—		725		725		792,543		793,268		725
Single-family residential mortgages		1,454		1,560		450		3,464		953,790		957,254		1,334
Commercial:
Commercial and industrial		—		—		—		—		274,586		274,586		—
SBA		2,263		—		9,378		11,641		63,344		74,985		9,378
Other:		—		—		—		—		821		821		—
	$	3,717	$	1,560	$	10,553	$	15,830	$	2,181,104	$	2,196,934	$	11,437
Real estate:
Single-family residential mortgages held for sale	$	—	$	—	$	—	$	—	$	108,194	$	108,194	$	—

December 31, 2018
Real estate:
Construction and land development	$	—	$	—	$	—	$	—	$	113,235	$	113,235	$	—
Commercial real estate		—		678		—		678		758,043		758,721		—
Single-family residential mortgages		1,548		950		—		2,498		878,751		881,249		—
Commercial:
Commercial and industrial		—		—		—		—		304,310		304,310		—
SBA		957		—		914		1,871		82,629		84,500		914
	$	2,505	$	1,628	$	914	$	5,047	$	2,136,968	$	2,142,015	$	914
Real estate:
Single-family residential mortgages held for sale	$	—	$	458	$	—	$	458	$	434,064	$	434,522	$	—

(1)	Included in total loans

Summary of Individually Impaired Loans Presented by Class of Loans

Information relating to individually impaired loans presented by class of loans was as follows as of December 31, 2019, 2018 and 2017:

	Unpaid
(dollars in thousands)	Principal		Recorded		Average		Interest		Related
December 31, 2019	Balance		Investment		Balance		Income		Allowance
With no related allowance recorded
Construction and land development	$	264	$	264	$	271	$	24	$	—
Commercial real estate		2,198		2,197		2,384		100		—
Residential mortgage loans		1,349		1,334		1,351		—		—
Commercial - SBA		9,423		9,423		10,791		4		—
With related allowance recorded
Commercial-SBA		—		—		—		—		—
Total	$	13,234	$	13,218	$	14,797	$	128	$	—

December 31, 2018
With no related allowance recorded
Construction and land development	$	276	$	276	$	283	$	23	$	—
Commercial real estate		2,033		2,033		2,126		134		—
Commercial - SBA		797		1,498		1,377		19		—
With related allowance recorded
Commercial-SBA		175		175		193		1		44
Total	$	3,281	$	3,982	$	3,979	$	177	$	44
December 31, 2017
With no related allowance recorded
Construction and land development	$	289	$	289	$	296	$	16	$	—
Commercial real estate		2,131		2,131		2,192		297		—
Commercial - SBA		155		155		78		15		—
Total	$	2,575	$	2,575	$	2,566	$	328	$	—

Summary of Loans by Class Modified as TDRs

The following table presents loans by class modified as TDR's that occurred during the year ended December 31, 2019:

Pre-

Post-

Modification

(dollars in thousands)

Number of

Recorded

December 31, 2019

Loans

Investment

Commercial real estate

476

Summary of Activity in Accretable Yield on Purchased Credit-impaired Loans

Below is a summary of activity in the accretable yield on purchased credit-impaired loans for 2019, 2018 and 2017:

(dollars in thousands)	2019		2018			2017
Beginning balance	$	—	$	7		$	142
Disposals		—		—			—
Restructuring as TDR		—		—			—
Accretion of income		—		(7	)		(135	)
Ending balance	$	—	$	—		$	7

Loan Servicing (Tables)

12 Months Ended

Dec. 31, 2019

Loan Servicing [Abstract]

Schedule of Principal Balances of Mortgage and SBA Loans Serviced for Others

Mortgage and SBA loans serviced for others are not reported as assets. The principal balances as of December 31, 2019 and 2018 are as follows:

(dollars in thousands)	2019		2018
Loans serviced for others:
Mortgage loans	$	1,683,298	$	1,586,499
SBA loans		170,849		184,664
Commercial real estate loans		4,216		2,838

Schedule of Activity for Servicing Assets

Activity for servicing assets follows:

	2019						2018						2017
	Mortgage			SBA			Mortgage			SBA			Mortgage			SBA
(dollars in thousands)	Loans			Loans			Loans			Loans			Loans			Loans
Servicing assets:
Beginning of period	$	12,858		$	4,512		$	1,540		$	4,417		$	1,002		$	2,702
Acquisitions		—			—			10,651			—			—			—
Additions		2,088			980			1,562			1,932			1,115			2,628
Disposals		(128	)		(708	)		(197	)		(1,177	)		(172	)		(367	)
Amortized to expense		(1,821	)		(698	)		(698	)		(660	)		(405	)		(546	)
End of period	$	12,997		$	4,086		$	12,858		$	4,512		$	1,540		$	4,417

Premises and Equipment (Tables)

12 Months Ended

Dec. 31, 2019

Property Plant And Equipment [Abstract]

Summary of Premises and Equipment

A summary of premises and equipment as of December 31 follows:

(dollars in thousands)	2019			2018
Land	$	5,020		$	5,020
Building and improvements		7,822			7,823
Furniture, fixtures, and equipment		6,252			4,833
Leasehold improvements		5,590			4,845
		24,684			22,521
Less accumulated depreciation and amortization		(8,102	)		(6,312	)
Construction in progress		231			1,098
	$	16,813		$	17,307

Schedule of Future Minimum Rent Payments on Company's Leases

Future minimum rent payments on the Company's leases were as follows as of December 31, 2019:

(dollars in thousands)
Year ending December 31:
2020	$	5,603
2021		4,634
2022		4,192
2023		3,250
2024		2,209
Thereafter		8,998
	$	28,886

Deposits (Tables)

12 Months Ended

Dec. 31, 2019

Maturities Of Time Deposits [Abstract]

Schedule of Maturities of Time Deposits

At December 31, 2019 the scheduled maturities of time deposits are as follows:

(dollars in thousands)
One year	$	1,215,913
Two to three years		34,863
Over three years		1,909
Total	$	1,252,685

Long-term Debt (Tables)

12 Months Ended

Dec. 31, 2019

Debt Disclosure [Abstract]

Schedule of Long-term Debt

At December 31, 2019 and 2018, respectively, long-term debt was as follows:

(dollars in thousands)	2019		2018
Principal	$	105,000	$	105,000
Unamortized debt issuance costs	$	951	$	1,292

Schedule of Interest and Amortization Expense

The following table presents interest and amortization expense the Company incurred for the year ended December 31, 2019 and 2018:

	For the Year Ended December 31,
(dollars in thousands)	2019		2018
Interest Expense:
Interest	$	6,649	$	3,552
Amortization		342		162

- Definition

Tabular disclosure of long-debt instruments or arrangements, including identification, terms, features, collateral requirements and other information necessary to a fair presentation. These are debt arrangements that originally required repayment more than twelve months after issuance or greater than the normal operating cycle of the entity, if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 1A
-URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28541-108399

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21506-112644

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(e),(f))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28551-108399

Reference 6: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21521-112644

Reference 7: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21538-112644

Reference 8: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=75038535&loc=d3e64711-112823

Reference 9: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400

Reference 10: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21475-112644

+ Details

Income Taxes (Tables)

12 Months Ended

Dec. 31, 2019

Income Tax Disclosure [Abstract]

Components of Income Tax Expense

Income tax expense consists of the following:

(dollars in thousands)	2019		2018			2017
Current:
Federal	$	8,074	$	6,616		$	12,097
State		5,614		3,451			3,773
		13,688		10,067			15,870
Deferred		1,503		(131	)		2,492
Deferred tax adjustment for change in tax rate		21		(479	)		2,591
Amortization of investment in affordable housing tax credits		900		644			316
	$	16,112	$	10,101		$	21,269

Comparison of Federal Statutory Income Tax Rates to Effective Income Tax Rates

A comparison of the federal statutory income tax rates to the Company's effective income tax rates as of December 31 follows:

	2019						2018						2017
(dollars in thousands)	Amount			Rate			Amount			Rate			Amount			Rate
Statutory federal tax	$	11,617			21.0	%	$	9,703		21.0%			$	16,379			35.0	%
State franchise tax, net of federal benefit		5,322			9.6	%		3,488		7.5%				3,135			6.7	%
Tax-exempt income		(25	)		0.0	%		(27	)	-0.1%				(297	)		-0.6	%
Tax impact from change in tax rate		17			0.0	%		(479	)	-1.0%				2,591			5.5	%
Stock-based compensation		(27	)		0.0	%		(2,643	)	-5.7%				—			0.0	%
Other items, net		(792	)		-1.4	%		59		0.1%				(539	)		-1.2	%
Actual tax expense	$	16,112			29.2	%	$	10,101			21.8	%	$	21,269			45.4	%

Components of Net Deferred Tax Asset

The following is a summary of the components of the net deferred tax asset accounts recognized in the accompanying balance sheets as of December 31:

(dollars in thousands)	2019			2018
Deferred tax assets:
Pre-opening expenses	$	122		$	154
Allowance for loan losses		5,883			5,545
Stock-based compensation		1,346			1,419
Off balance sheet reserve		258			217
Operating loss carryforwards		1,253			1,688
Other real estate owned		37			10
Unrealized loss on AFS securities		—			600
Mark to market on held for sale mortgage loans		359			2,451
Other		1,594			1,220
		10,852			13,304
Deferred tax liabilities:
Depreciation		(282	)		(521	)
Unrealized gain on AFS securities		(106	)		—
Acquisition accounting fair value adjustments		(2,671	)		(2,067	)
Mortgage servicing rights		(3,745	)		(3,586	)
Other		(1,722	)		(2,488	)
		(8,526	)		(8,662	)
Net deferred tax assets	$	2,326		$	4,642

Commitments (Tables)

12 Months Ended

Dec. 31, 2019

Commitments And Contingencies Disclosure [Abstract]

Schedule of Financial Commitments whose Contractual Amount Represents Credit Risk

As of December 31, 2019 and 2018, the Company had the following financial commitments whose contractual amount represents credit risk:

	2019				2018
	Fixed		Variable		Fixed		Variable
(dollars in thousands)	Rate		Rate		Rate		Rate
Commitments to make loans	$	—	$	167,496	$	5,211	$	125,610
Unused lines of credit		55,789		102,841		61,191		75,908
Commercial and similar letters of credit		—		358		1,042		—
Standby letters of credit		2,485		1,230		2,701		673
	$	58,274	$	271,925	$	70,145	$	202,191

Related Party Transactions (Tables)

12 Months Ended

Dec. 31, 2019

Schedule of Related Party Transactions

Loans to principal officers, directors, and their affiliates were as follows:

(dollars in thousands)	2019			2018
Beginning balance	$	3,600		$	2,300
New loans and advances		16,180			7,400
Repayments		(15,780	)	$	(6,100	)
Ending balance	$	4,000		$	3,600

Stock Option Plan (Tables)

12 Months Ended

Dec. 31, 2019

Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]

Schedule of Weighted Average Assumption for Fair Value of Option Grant Estimated Using Black-Scholes Option Pricing Model

	2019			2016
Expected volatility		35.0	%		35.0	%
Expected term	6.0 years			6.0 years
Expected dividends		1.90	%	None
Risk free rate		2.66	%		1.93	%
Grant date fair value	$	6.32		$	6.76

Summary of Stock Option Plan

A summary of the status of the Company's stock option plan as of December 31, 2019 and changes during the year then ended is presented below:

						Weighted-
				Weighted-		Average
				Average		Remaining	Aggregate
				Exercise		Contractual	Intrinsic
(dollars in thousands, except for share amounts)	Shares			Price		Term	Value
Outstanding at beginning of year		1,215,097		$	12.83
Granted		76,500			18.38
Exercised		(200,629	)		13.43
Outstanding at end of year		1,090,968		$	13.11	4.07 years	$	8,790
Options exercisable		1,014,468		$	12.72	3.69 years	$	8,577

Regulatory Matters (Tables)

12 Months Ended

Dec. 31, 2019

Banking And Thrift [Abstract]

Summary of Actual Capital Amounts and Ratios and Related Regulatory Requirements

The following table sets forth RBB Bancorp's consolidated and the Bank's actual capital amounts and ratios and related regulatory requirements for the Bank as of December 31, 2019:

						Amount of Capital Required
											To Be Well-Capitalized
						Minimum Required for					Under Prompt Corrective
	Actual					Capital Adequacy Purposes					Provisions
(dollars in thousands)	Amount		Ratio			Amount		Ratio			Amount		Ratio
As of December 31, 2019:
Tier 1 Leverage Ratio
Consolidated	$	353,572		12.89	%	NA		NA			NA		NA
Bank		417,036		15.23	%	$	108,150		4.0	%	$	135,187		5.0	%
Common Equity Tier 1 Risk-Based Capital Ratio
Consolidated	$	343,899		17.16	%	NA		NA			NA		NA
Bank		417,036		20.87	%		89,127		4.5	%		128,739		6.5	%
Tier 1 Risk-Based Capital Ratio
Consolidated	$	353,572		17.65	%	NA		NA			NA		NA
Bank		417,036		20.87	%		118,836		6.0	%		158,448		8.0	%
Total Risk-Based Capital Ratio
Consolidated	$	477,262		23.82	%	NA		NA			NA		NA
Bank		436,677		21.86	%		158,448		8.0	%		198,061		10.0	%

The following table sets forth RBB Bancorp's consolidated and the Bank's actual capital amounts and ratios and related regulatory requirements for the Bank as of December 31, 2018:

						Amount of Capital Required
											To Be Well-Capitalized
						Minimum Required for					Under Prompt Corrective
	Actual					Capital Adequacy Purposes					Provisions
(dollars in thousands)	Amount		Ratio			Amount		Ratio			Amount		Ratio
As of December 31, 2018:
Tier 1 Leverage Ratio
Consolidated	$	321,407		11.80	%	NA		NA			NA		NA
Bank		370,304		13.66	%	$	108,445		4.0	%	$	135,556		5.0	%
Common Equity Tier 1 Risk Based Capital Ratio
Consolidated	$	311,901		15.28	%	NA		NA			NA		NA
Bank		370,304		18.17	%	$	91,722		4.5	%	$	132,487		6.5	%
Tier 1 Risk-Based Capital Ratio
Consolidated	$	321,407		15.74	%	NA		NA			NA		NA
Bank		370,304		18.17	%		122,296		6.0	%	$	163,061		8.0	%
Total Risk-Based Capital Ratio
Consolidated	$	443,379		21.71	%	NA		NA			NA		NA
Bank		388,569		19.07	%	$	163,061		8.0	%	$	203,826		10.0	%

Fair Value Measurements (Tables)

12 Months Ended

Dec. 31, 2019

Fair Value Disclosures [Abstract]

Schedule of Hierarchy and Fair Value for Each Major Category of Assets and Liabilities Measured at Fair Value

The following table provides the hierarchy and fair value for each major category of assets and liabilities measured at fair value at December 31, 2019 and 2018:

(dollars in thousands)	Fair Value Measurements Using:
December 31, 2019	Level 1		Level 2		Level 3		Total
Assets measured at fair value:
On a recurring basis:
Securities available for sale
Government agency securities	$	—	$	1,572	$	—	$	1,572
SBA agency securities		—		4,691		—		4,691
Mortgage-backed securities		—		19,171		—		19,171
Collateralized mortgage obligations		—		11,654		—		11,654
Commercial paper		—		69,898				69,898
Corporate debt securities		—		19,083		—		19,083
	$	—	$	126,069	$	—	$	126,069
On a non-recurring basis:
Other real estate owned		—		—		293		293
	$	—	$	—	$	293	$	293

December 31, 2018	Level 1		Level 2		Level 3		Total
Assets measured at fair value:
On a recurring basis:
Securities available for sale
Government agency securities	$	—	$	1,815	$	—	$	1,815
SBA agency securities		—		5,169		—		5,169
Mortgage-backed securities		—		22,541		—		22,541
Collateralized mortgage obligations		—		12,066		—		12,066
Commercial paper		—		14,918				14,918
Corporate debt securities		—		17,253		—		17,253
	$	—	$	73,762	$	—	$	73,762
On a non-recurring basis:
Commercial real estate - collateral dependent impaired loans	$	—		—	$	123	$	123
Other real estate owned		—		—	$	1,101	$	1,101
	$	—	$	—	$	1,224	$	1,224

Summary of Quantitative Information About Non-recurring Level 3 Fair Value Measurements

Quantitative information about the Company's non-recurring Level 3 fair value measurements as of December 31, 2019 and 2018 is as follows:

Weighted-

(dollars in thousands)

Fair Value

Valuation

Unobservable

Adjustment

Average

December 31, 2019

Amount

Technique

Input

Range

Adjustment

Other real estate owned

293

Third Party

Management Adjustments

29%

Appraisals

to Reflect Current

Conditions and Selling

Costs

December 31, 2018

Other real estate owned

1,101

Third Party

Management Adjustments

16%

Appraisals

to Reflect Current

Conditions and Selling

Costs

- Definition

Tabular disclosure of financial instruments measured at fair value, including those classified in shareholders' equity measured on a recurring or nonrecurring basis. Disclosures include, but are not limited to, fair value measurements recorded and the reasons for the measurements, level within the fair value hierarchy in which the fair value measurements are categorized and transfers between levels 1 and 2. Nonrecurring fair value measurements are those that are required or permitted in the statement of financial position in particular circumstances.

+ References + Details

Fair Value of Financial Instruments (Tables)

12 Months Ended

Dec. 31, 2019

Fair Value Disclosures [Abstract]

Schedule of Fair Value Hierarchy Level and Estimated Fair Value of Significant Financial Instruments

The fair value hierarchy level and estimated fair value of significant financial instruments at December 31, 2019 and 2018 are summarized as follows:

		2019				2018
	Fair Value	Carrying		Fair		Carrying		Fair
(dollars in thousands)	Hierarchy	Value		Value		Value		Value
Financial Assets:
Cash and due from banks	Level 1	$	114,763	$	114,763	$	147,685	$	147,685
Federal funds sold and other cash equivalents	Level 1		67,000		67,000		—		—
Interest-earning deposits in other financial institutions	Level 1		600		600		600		600
Investment securities - AFS	Level 2		126,069		126,069		73,762		73,762
Investment securities - HTM	Level 2		8,332		8,632		9,961		9,940
Mortgage loans held for sale	Level 1		108,194		109,385		434,522		438,948
Loans, net	Level 3		2,178,118		2,158,970		2,124,438		2,114,341
Equity securities	Level 3		11,826		11,826		10,039		10,039
Mortgage servicing rights	Level 2		17,083		20,752		17,370		21,361

Financial Liabilities:
Deposits	Level 2	$	2,248,938	$	2,236,329	$	2,144,041	$	2,143,196
FHLB advances	Level 2		—		—		319,500		319,500
Long-term debt	Level 2		104,049		109,877		103,708		79,756
Subordinated debentures	Level 3		9,673		11,709		9,506		10,356

Earnings Per Share ("EPS") (Tables)

12 Months Ended

Dec. 31, 2019

Earnings Per Share [Abstract]

Reconciliation of Net Income and Shares Outstanding to Income and Number of Shares Used to Compute EPS

The following is a reconciliation of net income and shares outstanding to the income and number of shares used to compute EPS:

	2019						2018					2017
(dollars in thousands except per share amounts)	Income			Shares			Income		Shares			Income		Shares
Net income as reported	$	39,209					$	36,105				$	25,528
Less: Earnings allocated to Participating Securities		(74	)					—					—
Shares outstanding					20,030,866					20,000,022					15,908,893
Impact of weighting shares					(13,560	)				(2,848,800	)				(1,830,612	)
Used in basic EPS		39,135			20,017,306			36,105		17,151,222			25,528		14,078,281
Dilutive effect of outstanding
Stock options					376,118					816,431					1,160,084
Used in dilutive EPS	$	39,135			20,393,424		$	36,105		17,967,653		$	25,528		15,238,365

Basic earnings per common share	$	1.96					$	2.11				$	1.81
Diluted earnings per common share		1.92						2.01					1.68

Revenue From Contracts With Customers (Tables)

12 Months Ended

Dec. 31, 2019

Revenue From Contract With Customer [Abstract]

Summary of Revenue From Contracts With Customers in-Scope and Not in-Scope under Topic 606

The following is a summary of revenue from contracts with customers that are in-scope and not in-scope under Topic 606:

	For the Year Ended December 31,
(dollars in thousands)	2019			2018		2017
Non-interest income, in scope ⁽¹⁾
Fees and service charges on deposit accounts	$	1,366		$	1,115	$	1,164
Other fees ⁽²⁾		1,118			723		145
Other income ⁽³⁾		1,429			709		501
(Loss) gain on sale of OREO and fixed assets		(100	)		—		142
Total in-scope non-interest income		3,813			2,547		1,952
Non-interest income, not in scope ⁽⁴⁾		14,507			10,295		11,249
Total non-interest income	$	18,320		$	12,842	$	13,201

(1)	There were no adjustments to the Company's financial statements recorded as a result of the adoption of ASC 606.

(2)	Other fees consists of wealth management fees, miscellaneous loan fees and postage/courier fees.

(3)	Other income consists of safe deposit box rental income, wire transfer fees, security brokerage fees, annuity sales, insurance activity, and OREO income.

(4)

Parent Only Condensed Financial Information (Tables) - RBB Bancorp

12 Months Ended

Dec. 31, 2019

Condensed Financial Information Of Parent Company Only Disclosure [Line Items]

Schedule of Parent Only Condensed Statements of Financial Condition

Condensed Statements of Financial Condition

(Dollars in Thousands)	2019		2018
ASSETS
Cash and cash equivalents	$	29,985	$	45,540
Investment in Bank		480,703		433,023
Investment in RAM		6,870		6,796
Other assets		4,202		2,820
Total assets	$	521,760	$	488,179

LIABILITIES AND SHAREHOLDERS' EQUITY
Long term debt		104,049		103,708
Subordinated debentures		9,673		9,506
Other liabilities		348		344
Total liabilities		114,070		113,558
Shareholders' equity:
Common stock		290,395		288,610
Additional paid-in capital		4,938		5,659
Retained earnings		112,046		81,618
Non-controlling interest		72		72
Accumulated other comprehensive income (loss)		239		(1,338	)
Total shareholders' equity		407,690		374,621
Total liabilities and shareholders' equity	$	521,760	$	488,179

Schedule of Parent Only Condensed Statements of Income

Condensed Statements of Income

(Dollars in Thousands)	2019			2018			2017
Interest income	$	—		$	15		$	—
Interest expense		7,697			4,083			3,629
Noninterest expense		1,300			1,255			642
Loss before equity in undistributed income of subsidiaries		(8,997	)		(5,323	)		(4,271	)
Equity in undistributed income of:
Bank		45,324			39,198			27,620
RAM		74			528			143
Income before income taxes		36,401			34,403			23,492
Income tax benefit		2,808			1,702			2,036
Net income		39,209			36,105			25,528
Other comprehensive income (loss)		1,577			(895	)		(104	)
Total comprehensive income	$	40,786		$	35,210		$	25,424

Schedule of Parent Only Condensed Statements of Cash Flows

Condensed Statements of Cash Flows

(Dollars in Thousands)	2019			2018			2017
Cash flows from operating activities:
Net income	$	39,209		$	36,105		$	25,528
Net amortization of other		508			268			235
Provision for deferred income taxes		513			(1,905	)		1,807
Undistributed income of subsidiaries		(45,398	)		(39,726	)		(27,763	)
Change in other assets and liabilities		(1,981	)		3,492			(3,923	)
		(7,149	)		(1,766	)		(4,116	)
Cash flows from investment activities:
Net cash acquired (outlay) in connection with acquisition		—			(41,358	)		—
Investment in subsidiaries		—			(15,000	)		(25,000	)
		—			(56,358	)		(25,000	)
Cash flows from financing activities:
Issuance of subordinated debentures, net of issuance costs		—			54,018			—
Issuance of common stock, net of issuance costs		—			—			60,210
Dividends paid		(8,033	)		(5,753	)		(5,118	)
Common stock repurchased, net of repurchased costs		(3,190	)
Stock options exercised		2,817			9,630			2,296
		(8,406	)		57,895			57,388

Increase in cash and cash equivalents		(15,555	)		(229	)		28,272
Cash and cash equivalents beginning of year		45,540			45,769			17,497
Cash and cash equivalents end of year	$	29,985		$	45,540		$	45,769

Quarterly Income Statements (Unaudited) (Tables)

12 Months Ended

Dec. 31, 2019

Quarterly Financial Information Disclosure [Abstract]

Schedule of Quarterly Condensed Income Statements

The following table presents the unaudited quarterly condensed income statements for the years 2019 and 2018.

	2019								2018
(dollars in thousands)	4th Quarter		3rd Quarter		2nd Quarter		1st Quarter		4th Quarter		3rd Quarter		2nd Quarter		1st Quarter
Interest income	$	33,907	$	34,669	$	35,943	$	37,206	$	35,181	$	24,473	$	22,284	$	20,177
Interest expense		10,784		11,157		11,626		11,294		9,599		5,857		4,457		3,732
Net interest income		23,123		23,512		24,317		25,912		25,582		18,616		17,827		16,445
Provision for credit losses		659		824		357		550		1,890		1,695		700		184
Net interest income after provision for credit losses		22,464		22,688		23,960		25,362		23,692		16,921		17,127		16,261
Noninterest income:		5,823		2,799		5,496		4,202		5,489		2,105		2,793		2,455
Noninterest expense:		13,463		13,786		14,899		15,325		15,503		8,654		8,191		8,289
Income before income taxes		14,824		11,701		14,557		14,239		13,678		10,372		11,729		10,427
Income tax expense		4,149		3,689		4,415		3,859		4,188		2,041		2,292		1,580
Net income	$	10,675	$	8,012	$	10,142	$	10,380	$	9,490	$	8,331	$	9,437	$	8,847

Net income per share
Basic	$	0.53	$	0.40	$	0.51	$	0.52	$	0.48	$	0.50	$	0.58	$	0.55
Diluted		0.52		0.39		0.50		0.51		0.47		0.48		0.54		0.52

Business Description - Additional Information (Details) $ / shares in Units, $ in Thousands		12 Months Ended	87 Months Ended
	Jul. 31, 2017 $ / shares shares	Dec. 31, 2019 USD ($)	Oct. 15, 2018 Acquisition Branch	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Description Of Business [Line Items]
Total assets		$ 2,788,535		$ 2,974,002
Gross consolidated loans held for investment and held for sale		2,300,000
Total deposits		2,248,938		2,144,041
Total stockholders' Equity		$ 407,690		$ 374,621	$ 265,176	$ 181,585
Number of acquisitions \| Acquisition			5
First American International Bank \| Queens
Description Of Business [Line Items]
Number of branches operated \| Branch			3
First American International Bank \| Manhattan
Description Of Business [Line Items]
Number of branches operated \| Branch			2
First American International Bank \| Brooklyn
Description Of Business [Line Items]
Number of branches operated \| Branch			2
Initial Public Offering
Description Of Business [Line Items]
Number of shares issued in offering \| shares	3,750,000
Share price per share \| $ / shares	$ 23.00

Basis of Presentation and Summary of Significant Accounting Policies - Additional Information (Details)	3 Months Ended	12 Months Ended
	Mar. 31, 2019 USD ($)	Dec. 31, 2019 USD ($) Subsidiary Trust	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Number of inactive subsidiaries acquired \| Subsidiary		4
Number of statutory business trusts acquired \| Trust		2
Cash and due from banks, reserves required to be held		$ 29,500,000	$ 24,500,000
Debt securities evaluation for other-than-temporary impairment, measurement basis		quarterly
Threshold period past due principal or interest, to discontinue accrual of interest on loans		90 days
Gain on sale of loans		$ 9,893,000	7,126,000	$ 9,318,000
Gains on sale of mortgage loans, total		8,200,000	4,300,000	3,700,000
Gains on sale of SBA loans, total		1,500,000	2,800,000	5,600,000
Gains on sale of CRE, total		152,000	0	0
Goodwill		58,563,000	58,383,000
Impairment losses recognized on goodwill		0	0
Amortization of intangibles		4,856,000	3,302,000	1,845,000
Total gross loans		$ 2,300,000,000
Percentage of gross loans with LIBOR based reference rate		25.00%
Out-of-Scope Topic 606
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Percentage of non interest income		79.00%
ASU 2014-09
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Percentage of non interest income		21.00%
401(k) Plan
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Contributions to plan		$ 570,000	341,000	272,000
CRA Investments
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Carrying amount of equity securities without readily determinable fair values		11,800,000	10,000,000
Pacific Coast Bankers' Bank
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Carrying amount of equity securities without readily determinable fair values		324,000
Estimated gain on equity securities	$ 107,000
Atlantic Community Bankers’ Bank
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Carrying amount of equity securities without readily determinable fair values		100,000
Estimated gain on equity securities	$ 40,000
Core Deposit Intangible
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Unamortized balance of intangible assets		6,100,000	7,600,000
Accumulated amortization		3,100,000	1,600,000
Amortization of intangibles		$ 1,500,000	575,000	355,000
Premises
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Estimated useful life of assets		30 years
Mortgage, SBA and CRE
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Gain on sale of loans		$ 9,900,000	$ 7,100,000	$ 9,300,000
Minimum
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Right-of-use asset		25,000,000
Lease liability		$ 25,000,000
Minimum \| Core Deposit Intangible
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Intangible assets, estimated useful life		8 years
Minimum \| Leasehold Improvements
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Estimated useful life of assets		3 years
Minimum \| Equipment
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Estimated useful life of assets		3 years
Maximum
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Cash and cash equivalents maturity period		90 days
Right-of-use asset		$ 30,000,000
Lease liability		$ 30,000,000
Maximum \| Core Deposit Intangible
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Intangible assets, estimated useful life		10 years
Maximum \| Leasehold Improvements
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Estimated useful life of assets		10 years
Maximum \| Equipment
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Estimated useful life of assets		10 years

Basis of Presentation and Summary of Significant Accounting Policies - Schedule of Future Estimated Amortization Expense (Details) $ in Thousands	Dec. 31, 2019 USD ($)
Goodwill And Intangible Assets Disclosure [Abstract]
2020	$ 1,285
2021	1,056
2022	879
2023	749
2024	638
Thereafter	1,493
Total	$ 6,100

Acquisitions - Additional Information (Details) $ in Thousands			87 Months Ended
	Jan. 10, 2020 USD ($) Branch Business	Oct. 15, 2018 USD ($) Branch shares	Oct. 15, 2018 USD ($) Acquisition Branch	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Business Acquisition [Line Items]
Goodwill				$ 58,563	$ 58,383
Number of acquisitions \| Acquisition			5
First American International Corp.
Business Acquisition [Line Items]
Cash consideration		$ 34,837
Business acquisition, stock value of acquirer		$ 69,602
Business acquisition, common shares issued \| shares		3,011,762
Goodwill		$ 28,443	$ 28,443
Business Combination, Identifiable assets acquired		849,962	849,962
Deposits		$ 629,703	$ 629,703
First American International Corp. \| New York
Business Acquisition [Line Items]
Number of branches operated \| Branch		9	9
PGB \| Subsequent Event
Business Acquisition [Line Items]
Cash consideration	$ 32,900
Business acquisition, date	Jan. 10, 2020
PGB \| Illinois \| Subsequent Event
Business Acquisition [Line Items]
Business Combination, Identifiable assets acquired	$ 217,600
Deposits	$ 192,300
Number of acquisitions \| Business	1
Number of branches \| Branch	3

Acquisitions - Schedule of Assets Acquired and Liabilities Assumed and Fair Value Adjustments (Details) - USD ($) $ in Thousands	Oct. 15, 2018	Dec. 31, 2019	Dec. 31, 2018
Business Acquisition [Line Items]
Goodwill recognized		$ 58,563	$ 58,383
First American International Corp.
Business Acquisition [Line Items]
Cash and cash equivalents	$ 55,891
Fed funds sold	218
Interest-bearing deposits in other financial Institutions	3,801
Investments - held to maturity	30,203
Investments - available for sale	14,388
Mortgage loans held for sale	1,915
Loans, gross	715,571
Bank premises and equipment	9,224
Mortgage servicing rights	10,614
Core deposit premium	6,738
Other assets	1,399
Total assets acquired	849,962
Deposits	629,703
FHLB advances	124,500
Subordinated debentures	5,976
Other liabilities	13,787
Total liabilities assumed	773,966
Excess of assets acquired over liabilities assumed	75,996
Stock consideration	69,602
Cash paid	34,837
Goodwill recognized	28,443
First American International Corp. \| Book Value
Business Acquisition [Line Items]
Cash and cash equivalents	55,891
Fed funds sold	218
Interest-bearing deposits in other financial Institutions	3,801
Investments - held to maturity	30,814
Investments - available for sale	14,388
Mortgage loans held for sale	1,915
Loans, gross	721,732
Allowance for loan losses	(9,583)
Bank premises and equipment	5,785
Mortgage servicing rights	11,274
Other assets	3,518
Total assets acquired	839,753
Deposits	629,609
FHLB advances	124,500
Subordinated debentures	7,217
Other liabilities	14,940
Total liabilities assumed	776,266
Excess of assets acquired over liabilities assumed	63,487
Business combination, Recognized identifiable assets acquired and liabilities assumed, net	839,753
First American International Corp. \| Fair Value Adjustments
Business Acquisition [Line Items]
Investments - held to maturity	(611)
Loans, gross	(6,161)
Allowance for loan losses	9,583
Bank premises and equipment	3,439
Mortgage servicing rights	(660)
Core deposit premium	6,738
Other assets	(2,119)
Total assets acquired	10,209
Deposits	94
Subordinated debentures	(1,241)
Other liabilities	(1,153)
Total liabilities assumed	(2,300)
Excess of assets acquired over liabilities assumed	12,509
Business combination, Recognized identifiable assets acquired and liabilities assumed, net	$ 10,209

Investment Securities - Summary of Amortized Cost and Fair Value of Available for Sale Securities and Held to Maturity Securities - (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Available for sale, Amortized Cost	$ 125,729	$ 75,663
Available for sale, Gross Unrealized Gains	435	106
Available for sale, Gross Unrealized Losses	(95)	(2,007)
Available for sale, Fair Value	126,069	73,762
Held to maturity, Amortized Cost	8,332	9,961
Held to maturity, Gross Unrealized Gains	300	143
Held to maturity, Gross Unrealized Losses		(164)
Securities held to maturity, fair value	8,632	9,940
Government Agency Securities
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Available for sale, Amortized Cost	1,591	1,873
Available for sale, Gross Unrealized Losses	(19)	(58)
Available for sale, Fair Value	1,572	1,815
SBA Agency Securities
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Available for sale, Amortized Cost	4,671	5,354
Available for sale, Gross Unrealized Gains	42
Available for sale, Gross Unrealized Losses	(22)	(185)
Available for sale, Fair Value	4,691	5,169
Mortgage-Backed Securities - Government Sponsored Agencies
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Available for sale, Amortized Cost	19,126	23,125
Available for sale, Gross Unrealized Gains	74
Available for sale, Gross Unrealized Losses	(29)	(584)
Available for sale, Fair Value	19,171	22,541
Collateralized Mortgage Obligations
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Available for sale, Amortized Cost	11,641	12,696
Available for sale, Gross Unrealized Gains	38	1
Available for sale, Gross Unrealized Losses	(25)	(631)
Available for sale, Fair Value	11,654	12,066
Corporate Debt Securities
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Available for sale, Amortized Cost	88,700	32,615
Available for sale, Gross Unrealized Gains	281	105
Available for sale, Gross Unrealized Losses		(549)
Available for sale, Fair Value	88,981	32,171
Municipal Taxable Securities
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Held to maturity, Amortized Cost	3,505	4,290
Held to maturity, Gross Unrealized Gains	147	142
Securities held to maturity, fair value	3,652	4,432
Municipal Securities
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Held to maturity, Amortized Cost	4,827	5,671
Held to maturity, Gross Unrealized Gains	153	1
Held to maturity, Gross Unrealized Losses		(164)
Securities held to maturity, fair value	$ 4,980	$ 5,508

Investment Securities - Additional Information (Details)	12 Months Ended
	Dec. 31, 2019 USD ($) Security	Dec. 31, 2018 USD ($) Security	Dec. 31, 2017 USD ($)
Investments Debt And Equity Securities [Abstract]
Proceeds from sale of securities	$ 6,143,000	$ 44,591,000	$ 0
Gross gains recognized on sale of securities	$ 7,000	$ 5,000
Number of investment securities pledged as collateral \| Security	1	1
Fair value of securities pledged to secure local agency deposit	$ 627,000	$ 697,000

Investment Securities - Amortized Cost and Fair Value of Investment Securities Portfolio Expected Maturity (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Available-for-sale Securities, Debt Maturities, Amortized Cost Basis, Fiscal Year Maturity [Abstract]
Less than one year, Available for sale, Amortized Cost	$ 74,577
More than one year to five years, Available for sale, Amortized Cost	26,622
More than five years to ten years, Available for sale, Amortized Cost	20,518
More than ten years, Available for sale, Amortized Cost	4,012
Available for sale, Amortized Cost	125,729	$ 75,663
Available-for-sale Securities, Debt Maturities, Fair Value, Fiscal Year Maturity [Abstract]
Less than one year, Available for sale, Estimated Fair Value	74,598
More than one year, Available for sale, Estimated Fair Value	26,629
More than five years to ten years, Available for sale, Estimated Fair Value	20,812
More than ten years, Available for sale, Estimated Fair Value	4,030
Available for sale, Estimated Fair value	126,069	73,762
Held-to-maturity Securities, Debt Maturities, Net Carrying Amount [Abstract]
Less than one year, Held to Maturity, Amortized Cost	285
More than one year to five years, Held to Maturity, Amortized Cost	2,756
More than five years to ten years, Held to Maturity, Amortized Cost	870
Due from ten years and greater, Held to Maturity, Amortized Cost	4,421
Held to maturity, Amortized Cost	8,332	9,961
Held-to-maturity Securities, Debt Maturities, Fair Value, Fiscal Year Maturity [Abstract]
'Less than one year, Held to Maturity, Estimated Fair Value	289
More than one year to five years, Held to Maturity, Estimated Fair Value	2,824
More than five years to ten years, Held to maturity, Estimated Fair Value	958
More than Ten Years,Held to maturity estimated fair value	4,561
Held to Maturity, Estimated Fair Value	8,632	9,940
Government Agency Securities
Available-for-sale Securities, Debt Maturities, Amortized Cost Basis, Fiscal Year Maturity [Abstract]
More than one year to five years, Available for sale, Amortized Cost	1,591
Available for sale, Amortized Cost	1,591	1,873
Available-for-sale Securities, Debt Maturities, Fair Value, Fiscal Year Maturity [Abstract]
More than one year, Available for sale, Estimated Fair Value	1,572
Available for sale, Estimated Fair value	1,572	1,815
SBA Securities
Available-for-sale Securities, Debt Maturities, Amortized Cost Basis, Fiscal Year Maturity [Abstract]
More than one year to five years, Available for sale, Amortized Cost	714
More than five years to ten years, Available for sale, Amortized Cost	3,957
Available for sale, Amortized Cost	4,671	5,354
Available-for-sale Securities, Debt Maturities, Fair Value, Fiscal Year Maturity [Abstract]
More than one year, Available for sale, Estimated Fair Value	725
More than five years to ten years, Available for sale, Estimated Fair Value	3,966
Available for sale, Estimated Fair value	4,691	5,169
Mortgage-Backed Securities - Government Sponsored Agencies
Available-for-sale Securities, Debt Maturities, Amortized Cost Basis, Fiscal Year Maturity [Abstract]
Less than one year, Available for sale, Amortized Cost	3,663
More than one year to five years, Available for sale, Amortized Cost	13,027
More than five years to ten years, Available for sale, Amortized Cost	2,436
Available for sale, Amortized Cost	19,126	23,125
Available-for-sale Securities, Debt Maturities, Fair Value, Fiscal Year Maturity [Abstract]
Less than one year, Available for sale, Estimated Fair Value	3,679
More than one year, Available for sale, Estimated Fair Value	13,059
More than five years to ten years, Available for sale, Estimated Fair Value	2,433
Available for sale, Estimated Fair value	19,171	22,541
Collateralized Mortgage Obligations
Available-for-sale Securities, Debt Maturities, Amortized Cost Basis, Fiscal Year Maturity [Abstract]
More than one year to five years, Available for sale, Amortized Cost	9,288
More than five years to ten years, Available for sale, Amortized Cost	2,353
Available for sale, Amortized Cost	11,641	12,696
Available-for-sale Securities, Debt Maturities, Fair Value, Fiscal Year Maturity [Abstract]
More than one year, Available for sale, Estimated Fair Value	9,265
More than five years to ten years, Available for sale, Estimated Fair Value	2,389
Available for sale, Estimated Fair value	11,654	12,066
Corporate Debt Securities
Available-for-sale Securities, Debt Maturities, Amortized Cost Basis, Fiscal Year Maturity [Abstract]
Less than one year, Available for sale, Amortized Cost	70,914
More than one year to five years, Available for sale, Amortized Cost	2,002
More than five years to ten years, Available for sale, Amortized Cost	11,772
More than ten years, Available for sale, Amortized Cost	4,012
Available for sale, Amortized Cost	88,700	32,615
Available-for-sale Securities, Debt Maturities, Fair Value, Fiscal Year Maturity [Abstract]
Less than one year, Available for sale, Estimated Fair Value	70,919
More than one year, Available for sale, Estimated Fair Value	2,008
More than five years to ten years, Available for sale, Estimated Fair Value	12,024
More than ten years, Available for sale, Estimated Fair Value	4,030
Available for sale, Estimated Fair value	88,981	32,171
Municipal Taxable Securities
Held-to-maturity Securities, Debt Maturities, Net Carrying Amount [Abstract]
Less than one year, Held to Maturity, Amortized Cost	285
More than one year to five years, Held to Maturity, Amortized Cost	2,716
More than five years to ten years, Held to Maturity, Amortized Cost	504
Held to maturity, Amortized Cost	3,505	4,290
Held-to-maturity Securities, Debt Maturities, Fair Value, Fiscal Year Maturity [Abstract]
'Less than one year, Held to Maturity, Estimated Fair Value	289
More than one year to five years, Held to Maturity, Estimated Fair Value	2,784
More than five years to ten years, Held to maturity, Estimated Fair Value	579
Held to Maturity, Estimated Fair Value	3,652	4,432
Municipal Securities
Held-to-maturity Securities, Debt Maturities, Net Carrying Amount [Abstract]
More than one year to five years, Held to Maturity, Amortized Cost	40
More than five years to ten years, Held to Maturity, Amortized Cost	366
Due from ten years and greater, Held to Maturity, Amortized Cost	4,421
Held to maturity, Amortized Cost	4,827	5,671
Held-to-maturity Securities, Debt Maturities, Fair Value, Fiscal Year Maturity [Abstract]
More than one year to five years, Held to Maturity, Estimated Fair Value	40
More than five years to ten years, Held to maturity, Estimated Fair Value	379
More than Ten Years,Held to maturity estimated fair value	4,561
Held to Maturity, Estimated Fair Value	$ 4,980	$ 5,508

Investment Securities - Summary of Investment Securities With Unrealized Losses (Details) $ in Thousands	Dec. 31, 2019 USD ($) Security	Dec. 31, 2018 USD ($) Security
Schedule Of Available For Sale Securities [Line Items]
Less than Twelve Months Unrealized Losses	$ (56)	$ (73)
Less than Twelve Months Estimated Fair Value	$ 11,410	$ 6,240
Less than Twelve Months No. of Issuances \| Security	11	5
Twelve Months or More Unrealized Losses	$ (39)	$ (1,934)
Twelve Months or More Estimated Fair Value	$ 4,865	$ 46,498
Twelve Months or More No. of Issuances \| Security	8	41
Total Unrealized Losses	$ (95)	$ (2,007)
Total Estimated Fair Value	$ 16,275	$ 52,738
Available for sale, Total No. of Issuances \| Security	19	46
Held to maturity, Less than Twelve Months Unrealized Losses		$ (104)
Held to maturity, Less than Twelve Months Estimated Fair Value		$ 2,468
Held to maturity, Less than Twelve Months, No. of Issuances \| Security		6
Held to maturity, Twelve Months or More Unrealized Losses		$ (60)
Held to maturity, Twelve Months or More Estimated Fair Value		$ 2,174
Held to maturity, Twelve Months or More, No. of Issuances \| Security		4
Held to maturity, Total Unrealized Losses		$ (164)
Held to maturity, Total Estimated Fair Value		$ 4,642
Held to maturity, Total No. of Issuances \| Security		10
Government Agency Securities
Schedule Of Available For Sale Securities [Line Items]
Less than Twelve Months Unrealized Losses	$ (19)
Less than Twelve Months Estimated Fair Value	$ 1,572
Less than Twelve Months No. of Issuances \| Security	2
Twelve Months or More Unrealized Losses		$ (58)
Twelve Months or More Estimated Fair Value		$ 1,815
Twelve Months or More No. of Issuances \| Security		2
Total Unrealized Losses	$ (19)	$ (58)
Total Estimated Fair Value	$ 1,572	$ 1,815
Available for sale, Total No. of Issuances \| Security	2	2
SBA Securities
Schedule Of Available For Sale Securities [Line Items]
Less than Twelve Months Unrealized Losses	$ (22)
Less than Twelve Months Estimated Fair Value	$ 1,469
Less than Twelve Months No. of Issuances \| Security	2
Twelve Months or More Unrealized Losses		$ (185)
Twelve Months or More Estimated Fair Value		$ 5,169
Twelve Months or More No. of Issuances \| Security		4
Total Unrealized Losses	$ (22)	$ (185)
Total Estimated Fair Value	$ 1,469	$ 5,169
Available for sale, Total No. of Issuances \| Security	2	4
Mortgage-Backed Securities - Government Sponsored Agencies
Schedule Of Available For Sale Securities [Line Items]
Less than Twelve Months Unrealized Losses	$ (5)	$ (12)
Less than Twelve Months Estimated Fair Value	$ 2,631	$ 1,640
Less than Twelve Months No. of Issuances \| Security	4	1
Twelve Months or More Unrealized Losses	$ (24)	$ (572)
Twelve Months or More Estimated Fair Value	$ 3,912	$ 20,901
Twelve Months or More No. of Issuances \| Security	6	23
Total Unrealized Losses	$ (29)	$ (584)
Total Estimated Fair Value	$ 6,543	$ 22,541
Available for sale, Total No. of Issuances \| Security	10	24
Collateralized Mortgage Obligations
Schedule Of Available For Sale Securities [Line Items]
Less than Twelve Months Unrealized Losses	$ (10)
Less than Twelve Months Estimated Fair Value	$ 5,738
Less than Twelve Months No. of Issuances \| Security	3
Twelve Months or More Unrealized Losses	$ (15)	$ (631)
Twelve Months or More Estimated Fair Value	$ 953	$ 12,065
Twelve Months or More No. of Issuances \| Security	2	8
Total Unrealized Losses	$ (25)	$ (631)
Total Estimated Fair Value	$ 6,691	$ 12,065
Available for sale, Total No. of Issuances \| Security	5	8
Corporate Debt Securities
Schedule Of Available For Sale Securities [Line Items]
Less than Twelve Months Unrealized Losses		$ (61)
Less than Twelve Months Estimated Fair Value		$ 4,600
Less than Twelve Months No. of Issuances \| Security		4
Twelve Months or More Unrealized Losses		$ (488)
Twelve Months or More Estimated Fair Value		$ 6,548
Twelve Months or More No. of Issuances \| Security		4
Total Unrealized Losses		$ (549)
Total Estimated Fair Value		$ 11,148
Available for sale, Total No. of Issuances \| Security		8
Municipal Securities
Schedule Of Available For Sale Securities [Line Items]
Held to maturity, Less than Twelve Months Unrealized Losses		$ (104)
Held to maturity, Less than Twelve Months Estimated Fair Value		$ 2,468
Held to maturity, Less than Twelve Months, No. of Issuances \| Security		6
Held to maturity, Twelve Months or More Unrealized Losses		$ (60)
Held to maturity, Twelve Months or More Estimated Fair Value		$ 2,174
Held to maturity, Twelve Months or More, No. of Issuances \| Security		4
Held to maturity, Total Unrealized Losses		$ (164)
Held to maturity, Total Estimated Fair Value		$ 4,642
Held to maturity, Total No. of Issuances \| Security		10

Loans - Summary of Changes in Allowance for Loan Losses (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Allowance for loan losses:
Allowance for loan losses, Beginning balance	$ 17,577	$ 13,773	$ 14,162
Additions (reductions) to the allowance charged to expense	2,390	4,469	(1,053)
Recoveries on loans charged-off	108	36	747
Less loans charged-off	(1,259)	(701)	(83)
Allowance for loan losses, Ending balance	$ 18,816	$ 17,577	$ 13,773

Loans - Summary of Recorded Investment in Loans Impairment Method and Activity in Allowance for Loan Losses by Portfolio Segment (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Allowance for loan losses:
Allowance for loan losses, Beginning balance				$ 17,577				$ 13,773	$ 17,577	$ 13,773	$ 14,162
Allowance for loan losses, Provisions	$ 659	$ 824	$ 357	550	$ 1,890	$ 1,695	$ 700	184	2,390	4,469	(1,053)
Allowance for loan losses, Charge-offs									(1,259)	(701)	(83)
Allowance for loan losses, Recoveries									108	36	747
Allowance for loan losses, Ending balance	18,816				17,577				18,816	17,577	13,773
Reserves:
Loan losses, Reserves	18,816				17,577				18,816	17,577	13,773
Loans evaluated for impairment:
Loans, Individually evaluated for impairment	13,218				3,281				13,218	3,281	2,575
Loans, Collectively evaluated for impairment	2,183,716				2,138,734				2,183,716	2,138,734	1,246,184
Total loans, net of deferred loan fees	2,196,934				2,142,015				2,196,934	2,142,015	1,249,074
Loans acquired	2,300,000								2,300,000
Loans Acquired with Deteriorated Credit Quality
Loans evaluated for impairment:
Loans acquired											315
Specific Reserves
Reserves:
Loan losses, Reserves					44					44
General Reserves
Reserves:
Loan losses, Reserves	18,816				17,533				18,816	17,533	13,773
Real Estate
Allowance for loan losses:
Allowance for loan losses, Beginning balance				13,437				9,309	13,437	9,309	8,111
Allowance for loan losses, Provisions									1,847	4,128	1,198
Allowance for loan losses, Charge-offs									(166)
Allowance for loan losses, Ending balance	15,118				13,437				15,118	13,437	9,309
Reserves:
Loan losses, Reserves	15,118				13,437				15,118	13,437	9,309
Loans evaluated for impairment:
Loans, Individually evaluated for impairment	3,795				2,309				3,795	2,309	2,420
Loans, Collectively evaluated for impairment	1,842,747				1,750,896				1,842,747	1,750,896	834,152
Total loans, net of deferred loan fees	1,846,542				1,753,205				1,846,542	1,753,205	836,887
Real Estate \| Loans Acquired with Deteriorated Credit Quality
Loans evaluated for impairment:
Loans acquired											315
Real Estate \| General Reserves
Reserves:
Loan losses, Reserves	15,118				13,393				15,118	13,393	9,309
Commercial
Allowance for loan losses:
Allowance for loan losses, Beginning balance				$ 4,140				4,044	4,140	4,044	6,051
Allowance for loan losses, Provisions									433	761	(2,671)
Allowance for loan losses, Charge-offs									(1,093)	(701)	(83)
Allowance for loan losses, Recoveries									108	36	747
Allowance for loan losses, Ending balance	3,588				4,140				3,588	4,140	4,044
Reserves:
Loan losses, Reserves	3,588				4,140				3,588	4,140	4,044
Loans evaluated for impairment:
Loans, Individually evaluated for impairment	9,423				972				9,423	972	155
Loans, Collectively evaluated for impairment	340,148				387,838				340,148	387,838	412,032
Total loans, net of deferred loan fees	349,571				388,810				349,571	388,810	412,187
Commercial \| Specific Reserves
Reserves:
Loan losses, Reserves					44					44
Commercial \| General Reserves
Reserves:
Loan losses, Reserves	3,588				$ 4,140				3,588	4,140	4,044
Other
Allowance for loan losses:
Allowance for loan losses, Provisions									9
Allowance for loan losses, Ending balance	9								9
Reserves:
Loan losses, Reserves	9								9
Loans evaluated for impairment:
Loans, Collectively evaluated for impairment	821								821
Total loans, net of deferred loan fees	821								821
Other \| General Reserves
Reserves:
Loan losses, Reserves	9								9
Unallocated
Allowance for loan losses:
Allowance for loan losses, Beginning balance								$ 420		420
Allowance for loan losses, Provisions									101	$ (420)	420
Allowance for loan losses, Ending balance	101								101		420
Reserves:
Loan losses, Reserves	101								101		420
Unallocated \| General Reserves
Reserves:
Loan losses, Reserves	$ 101								$ 101		$ 420

Loans - Summary of Risk Category of Loans by Class of Loans (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Accounts Notes And Loans Receivable [Line Items]
Total loans	$ 2,196,934	$ 2,142,015
Real Estate \| Construction and Land Development
Accounts Notes And Loans Receivable [Line Items]
Total loans	96,020	113,235
Real Estate \| Commercial Real Estate
Accounts Notes And Loans Receivable [Line Items]
Total loans	793,268	758,721
Real Estate \| Single-family Residential Mortgages
Accounts Notes And Loans Receivable [Line Items]
Total loans	957,254	881,249
Commercial \| Commercial and Industrial
Accounts Notes And Loans Receivable [Line Items]
Total loans	274,586	304,310
Commercial \| SBA
Accounts Notes And Loans Receivable [Line Items]
Total loans	74,985	84,500
Other
Accounts Notes And Loans Receivable [Line Items]
Total loans	821
Pass
Accounts Notes And Loans Receivable [Line Items]
Total loans	2,146,181	2,111,225
Pass \| Real Estate \| Construction and Land Development
Accounts Notes And Loans Receivable [Line Items]
Total loans	95,756	112,959
Pass \| Real Estate \| Commercial Real Estate
Accounts Notes And Loans Receivable [Line Items]
Total loans	767,603	743,123
Pass \| Real Estate \| Single-family Residential Mortgages
Accounts Notes And Loans Receivable [Line Items]
Total loans	955,327	880,860
Pass \| Commercial \| Commercial and Industrial
Accounts Notes And Loans Receivable [Line Items]
Total loans	265,178	295,226
Pass \| Commercial \| SBA
Accounts Notes And Loans Receivable [Line Items]
Total loans	61,496	79,057
Pass \| Other
Accounts Notes And Loans Receivable [Line Items]
Total loans	821
Special Mention
Accounts Notes And Loans Receivable [Line Items]
Total loans	9,620	13,355
Special Mention \| Real Estate \| Commercial Real Estate
Accounts Notes And Loans Receivable [Line Items]
Total loans	5,353	7,069
Special Mention \| Commercial \| Commercial and Industrial
Accounts Notes And Loans Receivable [Line Items]
Total loans	4,078	6,286
Special Mention \| Commercial \| SBA
Accounts Notes And Loans Receivable [Line Items]
Total loans	189
Substandard
Accounts Notes And Loans Receivable [Line Items]
Total loans	27,915	14,154
Substandard \| Real Estate \| Commercial Real Estate
Accounts Notes And Loans Receivable [Line Items]
Total loans	18,115	6,496
Substandard \| Real Estate \| Single-family Residential Mortgages
Accounts Notes And Loans Receivable [Line Items]
Total loans	593	389
Substandard \| Commercial \| Commercial and Industrial
Accounts Notes And Loans Receivable [Line Items]
Total loans	5,330	2,798
Substandard \| Commercial \| SBA
Accounts Notes And Loans Receivable [Line Items]
Total loans	3,877	4,471
Impaired
Accounts Notes And Loans Receivable [Line Items]
Total loans	13,218	3,281
Impaired \| Real Estate \| Construction and Land Development
Accounts Notes And Loans Receivable [Line Items]
Total loans	264	276
Impaired \| Real Estate \| Commercial Real Estate
Accounts Notes And Loans Receivable [Line Items]
Total loans	2,197	2,033
Impaired \| Real Estate \| Single-family Residential Mortgages
Accounts Notes And Loans Receivable [Line Items]
Total loans	1,334
Impaired \| Commercial \| SBA
Accounts Notes And Loans Receivable [Line Items]
Total loans	$ 9,423	$ 972

Loans - Summary of Aging Recorded Investment Past-due Loans (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due	$ 15,830	$ 5,047
Loans Not Past Due	2,181,104	2,136,968
Total Loans	2,196,934	2,142,015
Non-Accrual Loans	11,437	914
30-59 Days
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due	3,717	2,505
60-89 Days
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due	1,560	1,628
90 Days Or More
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due	10,553	914
Real Estate \| Construction and Land Development
Financing Receivable Recorded Investment Past Due [Line Items]
Loans Not Past Due	96,020	113,235
Total Loans	96,020	113,235
Real Estate \| Commercial Real Estate
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due	725	678
Loans Not Past Due	792,543	758,043
Total Loans	793,268	758,721
Non-Accrual Loans	725
Real Estate \| Single-family Residential Mortgages
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due	3,464	2,498
Loans Not Past Due	953,790	878,751
Total Loans	957,254	881,249
Non-Accrual Loans	1,334
Real Estate \| Single-family residential mortgages held for sale
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due		458
Loans Not Past Due	108,194	434,064
Total Loans	108,194	434,522
Real Estate \| 30-59 Days \| Single-family Residential Mortgages
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due	1,454	1,548
Real Estate \| 60-89 Days \| Commercial Real Estate
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due		678
Real Estate \| 60-89 Days \| Single-family Residential Mortgages
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due	1,560	950
Real Estate \| 60-89 Days \| Single-family residential mortgages held for sale
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due		458
Real Estate \| 90 Days Or More \| Commercial Real Estate
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due	725
Real Estate \| 90 Days Or More \| Single-family Residential Mortgages
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due	450
Commercial \| SBA
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due	11,641	1,871
Loans Not Past Due	63,344	82,629
Total Loans	74,985	84,500
Non-Accrual Loans	9,378	914
Commercial \| Commercial and Industrial
Financing Receivable Recorded Investment Past Due [Line Items]
Loans Not Past Due	274,586	304,310
Total Loans	274,586	304,310
Commercial \| 30-59 Days \| SBA
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due	2,263	957
Commercial \| 90 Days Or More \| SBA
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due	9,378	$ 914
Other
Financing Receivable Recorded Investment Past Due [Line Items]
Loans Not Past Due	821
Total Loans	$ 821

Loans - Summary of Individually Impaired Loans Presented by Class of Loans (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Financing Receivable Impaired [Line Items]
Unpaid Principal Balance	$ 13,234	$ 3,281	$ 2,575
Recorded Investment	13,218	3,982	2,575
Average Balance	14,797	3,979	2,566
Interest Income	128	177	328
Construction and Land Development
Financing Receivable Impaired [Line Items]
Unpaid Principal Balance, With no related allowance recorded	264	276	289
Recorded Investment, With no related allowance recorded	264	276	289
Average Balance, With no related allowance recorded	271	283	296
Interest Income, With no related allowance recorded	24	23	16
Commercial Real Estate
Financing Receivable Impaired [Line Items]
Unpaid Principal Balance, With no related allowance recorded	2,198	2,033	2,131
Recorded Investment, With no related allowance recorded	2,197	2,033	2,131
Average Balance, With no related allowance recorded	2,384	2,126	2,192
Interest Income, With no related allowance recorded	100	134	297
Residential mortgage loans
Financing Receivable Impaired [Line Items]
Unpaid Principal Balance, With no related allowance recorded	1,349
Recorded Investment, With no related allowance recorded	1,334
Average Balance, With no related allowance recorded	1,351
Commercial \| SBA
Financing Receivable Impaired [Line Items]
Unpaid Principal Balance, With no related allowance recorded	9,423	797	155
Recorded Investment, With no related allowance recorded	9,423	1,498	155
Average Balance, With no related allowance recorded	10,791	1,377	78
Interest Income, With no related allowance recorded	4	19	$ 15
Unpaid Principal Balance, With related allowance recorded	0	175
Recorded Investment, With related allowance recorded	0	175
Average Balance, With related allowance recorded	0	193
Interest Income, With related allowance recorded	0	1
Related Allowance, With related allowance recorded	$ 0	$ 44

Loans - Additional Information (Details)	12 Months Ended
Loans - Additional Information (Details)	Dec. 31, 2019 USD ($) Loan	Dec. 31, 2018 USD ($) Loan	Dec. 31, 2017 USD ($)
Financing Receivable Recorded Investment [Line Items]
Interest income recognized on cash basis	$ 0	$ 0	$ 0
Interest income on nonaccrual loans	0	0
Troubled debt restructurings interest income	$ 128,000	$ 177,000
Number of loans identified as troubled debt restructurings \| Loan	4	4
Reserve for loans	$ 18,816,000	$ 17,577,000	$ 13,773,000
Commitments to lend an additional amounts of outstanding loans are classified as TDR's	$ 0	$ 0
Number of loans defaulted \| Loan	0	0
Outstanding balance of purchased credit-impaired loan	$ 0	$ 0
Minimum
Financing Receivable Recorded Investment [Line Items]
Moratorium on loan payments period granted	3 months
Maximum
Financing Receivable Recorded Investment [Line Items]
Moratorium on loan payments period granted	6 months
Specific Reserves
Financing Receivable Recorded Investment [Line Items]
Reserve for loans		44,000
One Loan \| Specific Reserves
Financing Receivable Recorded Investment [Line Items]
Reserve for loans	$ 0	$ 0

Loans - Summary of Loans by Class Modified as TDRs (Details) - Commercial Real Estate $ in Thousands	12 Months Ended
	Dec. 31, 2019 USD ($) Loan
Financing Receivable Recorded Investment [Line Items]
Number of Loans \| Loan	1
Pre-Modification Recorded Investment	$ 476
Post-Modification Recorded Investment	$ 476

Loans - Summary of Activity in Accretable Yield on Purchased Credit-impaired Loans (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Receivables [Abstract]
Beginning balance	$ 7	$ 142
Accretion of income	$ (7)	(135)
Ending balance		$ 7

Loan Servicing - Schedule of Principal Balances of Mortgage and SBA Loans Serviced for Others (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Mortgage Loans
Schedule Of Mortgage And Small Business Administration Loans Serviced [Line Items]
Loans serviced for others	$ 1,683,298	$ 1,586,499
SBA Loans
Schedule Of Mortgage And Small Business Administration Loans Serviced [Line Items]
Loans serviced for others	170,849	184,664
Commercial Real Estate Loans
Schedule Of Mortgage And Small Business Administration Loans Serviced [Line Items]
Loans serviced for others	$ 4,216	$ 2,838

Loan Servicing - Schedule of Activity for Servicing Assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Mortgage Loans
Servicing assets:
Beginning of period	$ 12,858	$ 1,540	$ 1,002
Acquisitions		10,651
Additions	2,088	1,562	1,115
Disposals	(128)	(197)	(172)
Amortized to expense	(1,821)	(698)	(405)
End of period	12,997	12,858	1,540
SBA Loans
Servicing assets:
Beginning of period	4,512	4,417	2,702
Additions	980	1,932	2,628
Disposals	(708)	(1,177)	(367)
Amortized to expense	(698)	(660)	(546)
End of period	$ 4,086	$ 4,512	$ 4,417

Loan Servicing - Additional Information (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Loan Sales And Mortgage Servicing Rights [Line Items]
Servicing assets	$ 17,083	$ 17,370
Servicing fees net of servicing asset amortization	3,383	850	$ 722
Mortgage Loans
Loan Sales And Mortgage Servicing Rights [Line Items]
Servicing assets	$ 15,100	$ 15,300
Mortgage Loans \| Fair Value Discount Rate
Loan Sales And Mortgage Servicing Rights [Line Items]
Fair value of servicing assets percentage	10.82	10.59
Mortgage Loans \| Fair Value Prepayment Rate \| Minimum
Loan Sales And Mortgage Servicing Rights [Line Items]
Fair value of servicing assets percentage	7.27	8.26
Mortgage Loans \| Fair Value Prepayment Rate \| Maximum
Loan Sales And Mortgage Servicing Rights [Line Items]
Fair value of servicing assets percentage	20.15	16.82
Mortgage Loans \| Fair Value Weighted Average Default Rate
Loan Sales And Mortgage Servicing Rights [Line Items]
Fair value of servicing assets percentage	0.11	0.20
SBA Loans
Loan Sales And Mortgage Servicing Rights [Line Items]
Servicing assets	$ 5,600	$ 6,100
SBA Loans \| Fair Value Discount Rate
Loan Sales And Mortgage Servicing Rights [Line Items]
Fair value of servicing assets percentage	8.50	8.50
SBA Loans \| Fair Value Prepayment Rate \| Minimum
Loan Sales And Mortgage Servicing Rights [Line Items]
Fair value of servicing assets percentage	12.50	11.43
SBA Loans \| Fair Value Prepayment Rate \| Maximum
Loan Sales And Mortgage Servicing Rights [Line Items]
Fair value of servicing assets percentage	14.66	12.11
SBA Loans \| Fair Value Weighted Average Default Rate
Loan Sales And Mortgage Servicing Rights [Line Items]
Fair value of servicing assets percentage	0.43	0.52

Premises and Equipment - Summary of Premises and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Property Plant And Equipment [Line Items]
Premises and equipment, gross	$ 24,684	$ 22,521
Less accumulated depreciation and amortization	(8,102)	(6,312)
Construction in progress	231	1,098
Premises and equipment	16,813	17,307
Land
Property Plant And Equipment [Line Items]
Premises and equipment, gross	5,020	5,020
Building and Improvements
Property Plant And Equipment [Line Items]
Premises and equipment, gross	7,822	7,823
Leasehold Improvements
Property Plant And Equipment [Line Items]
Premises and equipment, gross	5,590	4,845
Furnitures, Fixtures and Equipment
Property Plant And Equipment [Line Items]
Premises and equipment, gross	$ 6,252	$ 4,833

Premises and Equipment - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Property Plant And Equipment [Abstract]
Depreciation and leasehold amortization expense		$ 1,800,000	$ 989,000	$ 686,000
Operating leases expire at various dates through year	2028
Total rental expense, recognized on straight-line basis	$ 6,100,000	$ 2,700,000	$ 1,500,000
Operating lease expiration date	2018-05
Sub-lease income	$ 197,000

Premises and Equipment - Schedule of Future Minimum Rent Payments on Company's Leases (Details) $ in Thousands	Dec. 31, 2019 USD ($)
Commitments And Contingencies Disclosure [Abstract]
2020	$ 5,603
2021	4,634
2022	4,192
2023	3,250
2024	2,209
Thereafter	8,998
Total	$ 28,886

Deposits - Schedule of Maturities of Time Deposits (Details) $ in Thousands	Dec. 31, 2019 USD ($)
Maturities Of Time Deposits [Abstract]
One year	$ 1,215,913
Two to three years	34,863
Over three years	1,909
Total	$ 1,252,685

Deposits - Additional Information (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Maturities Of Time Deposits [Abstract]
Brokered time deposits	$ 67.1	$ 113.8

Long-term Debt - Schedule of Long-term Debt (Details) - USD ($)	Dec. 31, 2019	Dec. 31, 2018
Debt Instruments [Abstract]
Principal	$ 105,000,000	$ 105,000,000
Unamortized debt issuance costs	$ 951,000	$ 1,292,000

Long-term Debt - Additional Information (Details) - USD ($)	1 Months Ended		12 Months Ended
	Nov. 30, 2018	Mar. 31, 2016	Dec. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Debt instrument, face amount			$ 105,000,000	$ 105,000,000
6.5% Fixed to Floating Rate Subordinated Debentures, Due March 31, 2026
Debt Instrument [Line Items]
Debt instrument, face amount		$ 50,000,000
Long-term debt, fixed interest rate		6.50%
Debt instrument, due date		Mar. 31, 2026
Debt instrument, fixed to floating interest rate conversion date		Mar. 31, 2021
Debt instrument, floating rate description			3 month LIBOR plus 516 basis points
Debt instrument, basis points		5.16%
Tier-1 capital			$ 35,000,000
Debt instrument, redemption period, start date			Mar. 31, 2021
6.18% Fixed to Floating Rate Subordinated Debentures, Due December 1, 2028
Debt Instrument [Line Items]
Debt instrument, face amount	$ 55,000,000
Long-term debt, fixed interest rate	6.18%
Debt instrument, due date	Dec. 01, 2028
Debt instrument, fixed to floating interest rate conversion date	Dec. 01, 2023
Debt instrument, floating rate description			3 month LIBOR plus 315 basis points
Debt instrument, basis points	3.15%
Tier-1 capital			$ 25,000,000
Debt instrument, redemption period, start date			Dec. 01, 2023

Long-term Debt - Schedule of Interest and Amortization Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Interest Expense:
Interest	$ 6,649	$ 3,552
Amortization	$ 342	$ 162

Subordinated Debentures - Additional Information (Details) - USD ($)			1 Months Ended	12 Months Ended
	Feb. 19, 2016	Mar. 15, 2012	Oct. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Debt instrument, face amount				$ 105,000,000	$ 105,000,000
Interest expenses, paid				6,649,000	3,552,000
Debt aggregate amortization expense				$ 167,000	$ 106,000	$ 90,000
Subordinated Debentures
Debt Instrument [Line Items]
Percentage of principal amount redeemed		100.00%
Debt instrument redemption period				Mar. 15, 2012
Debt instrument maturity period				Mar. 15, 2037
Defer interest payments maximum period				5 years
Debt instrument interest rate description				three month London Interbank Offered Rate (LIBOR) plus 1.65%, which was 3.54% as of December 31, 2019 and 4.66% at December 31, 2018.
Debt instrument interest percentage				3.54%	4.66%
Interest expenses, paid				$ 540,000	$ 263,000	$ 144,000
TFC Statutory Trust \| Private Offering
Debt Instrument [Line Items]
Number of trust preferred securities	5,000
Trust preferred securities liquidation amount per preferred security	$ 1,000
TFC Statutory Trust \| Subordinated Debentures
Debt Instrument [Line Items]
Debt instrument, face amount	$ 5,000,000
Debt valuation reserve				1,900,000
TFC Statutory Trust \| Fair Value, Inputs, Level 1
Debt Instrument [Line Items]
Subordinated debenture liability	$ 3,300,000
First American International Statutory Trust I
Debt Instrument [Line Items]
Number of units issued			7,000
Aggregate liquidation amount of units issued			$ 7,000,000
Floating rate maturity period			30 years
First American International Statutory Trust I \| Subordinated Debentures
Debt Instrument [Line Items]
Debt instrument, face amount			$ 7,000,000
Debt valuation reserve				$ 1,200,000
Debt instrument maturity period				Dec. 15, 2034
Defer interest payments maximum period				5 years
Debt instrument interest rate description				the three-month LIBOR plus 2.25% through final maturity on December 15, 2034. The rate at December 31, 2019, was 4.14% and 5.04% at December 31, 2018.
Debt instrument interest percentage				4.14%	5.04%
Other Assets
Debt Instrument [Line Items]
Investment in common stock				$ 155,000
Other Assets \| First American International Statutory Trust I
Debt Instrument [Line Items]
Investment in common stock				$ 217,000
London Interbank Offered Rate \| Subordinated Debentures
Debt Instrument [Line Items]
Debt instrument, basis points				1.65%
London Interbank Offered Rate \| First American International Statutory Trust I \| Subordinated Debentures
Debt Instrument [Line Items]
Debt instrument, basis points				2.25%

Borrowing Arrangements - Additional Information (Details) - USD ($)	Dec. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Line of credit amount outstanding	$ 0	$ 0
Overnight advances with FHLB	0	$ 319,500,000
FRB Secured Line of Credit
Debt Instrument [Line Items]
Borrowing capacity	14,300,000
Carrying value of collateral loan pledged	28,700,000
FHLB Secured Line of Credit
Debt Instrument [Line Items]
Borrowing capacity	636,500,000
Carrying value of collateral loan pledged	727,800,000
FHLB
Debt Instrument [Line Items]
Overnight advances interest percentage		2.56%
Zions Bank
Debt Instrument [Line Items]
Borrowing capacity	20,000,000
Wells Fargo Bank
Debt Instrument [Line Items]
Borrowing capacity	10,000,000
Wells Fargo Bank \| Letter of Credit
Debt Instrument [Line Items]
Borrowing capacity	2,000,000
First Tennessee National Bank
Debt Instrument [Line Items]
Borrowing capacity	12,000,000
Pacific Coast Bankers' Bank
Debt Instrument [Line Items]
Borrowing capacity	$ 5,000,000

Income Taxes - Components of Income Tax Expense (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Current:
Federal									$ 8,074	$ 6,616	$ 12,097
State									5,614	3,451	3,773
Current									13,688	10,067	15,870
Deferred									1,503	(131)	2,492
Deferred tax adjustment for change in tax rate									21	(479)	2,591
Amortization of investment in affordable housing tax credits									900	644	316
Income tax expense	$ 4,149	$ 3,689	$ 4,415	$ 3,859	$ 4,188	$ 2,041	$ 2,292	$ 1,580	$ 16,112	$ 10,101	$ 21,269

Income Taxes - Comparison of Federal Statutory Income Tax Rates to Effective Income Tax Rates (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Amount
Statutory federal tax									$ 11,617	$ 9,703	$ 16,379
State franchise tax, net of federal benefit									5,322	3,488	3,135
Tax-exempt income									(25)	(27)	(297)
Tax impact from change in tax rate									17	(479)	2,591
Stock-based compensation									(27)	(2,643)
Other items, net									(792)	59	(539)
Income tax expense	$ 4,149	$ 3,689	$ 4,415	$ 3,859	$ 4,188	$ 2,041	$ 2,292	$ 1,580	$ 16,112	$ 10,101	$ 21,269
Rate
Statutory federal tax									21.00%	21.00%	35.00%
State franchise tax, net of federal benefit									9.60%	7.50%	6.70%
Tax-exempt income									(0.00%)	(0.10%)	(0.60%)
Tax impact from change in tax rate									0.00%	(1.00%)	5.50%
Stock-based compensation									0.00%	(5.70%)	0.00%
Other items, net									(1.40%)	0.10%	(1.20%)
Actual tax expense									29.20%	21.80%	45.40%

Income Taxes - Components of Net Deferred Tax Asset (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Deferred tax assets:
Pre-opening expenses	$ 122	$ 154
Allowance for loan losses	5,883	5,545
Stock-based compensation	1,346	1,419
Off balance sheet reserve	258	217
Operating loss carryforwards	1,253	1,688
Other real estate owned	37	10
Unrealized loss on AFS securities		600
Mark to market on held for sale mortgage loans	359	2,451
Other	1,594	1,220
Deferred tax assets	10,852	13,304
Deferred tax liabilities:
Depreciation	(282)	(521)
Unrealized gain on AFS securities	(106)
Acquisition accounting fair value adjustments	(2,671)	(2,067)
Mortgage servicing rights	(3,745)	(3,586)
Other	(1,722)	(2,488)
Deferred tax liabilities	(8,526)	(8,662)
Net deferred tax assets	$ 2,326	$ 4,642

Income Taxes - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Tax [Line Items]
Net operating loss carry forwards expiration, description	begin to expire in 2028
Net operating loss carry forwards expiration year start	2028
Income tax return examination, description	Income tax returns for the years ended after December 31, 2015 are open to audit by the federal and New York authorities and for the years ended after December 31, 2014 are open to audit by California state authorities.
Interest or penalties related to uncertain tax positions	$ 0	$ 0	$ 0
Adjustment to uncertain tax position	0
California Tax
Income Tax [Line Items]
Net operating loss carryforwards	0
Net operating loss carryforwards, subject to 382 limitations	11,400,000
New York State Income Tax
Income Tax [Line Items]
Net operating loss carryforwards	9,600,000
Net operating loss carryforwards, subject to 382 limitations	12,300,000
New York City Income Tax
Income Tax [Line Items]
Net operating loss carryforwards	8,800,000
Net operating loss carryforwards, subject to 382 limitations	9,300,000
Federal
Income Tax [Line Items]
Net operating loss carryforwards	32,000
Net operating loss carryforwards, subject to 382 limitations	$ 3,800,000

Commitments - Schedule of Financial Commitments whose Contractual Amount Represents Credit Risk (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Loss Contingencies [Line Items]
Financial commitments, contractual amount, Fixed Rate	$ 58,274	$ 70,145
Financial commitments, contractual amount, Variable Rate	271,925	202,191
Commitments to Make Loans
Loss Contingencies [Line Items]
Financial commitments, contractual amount, Fixed Rate		5,211
Financial commitments, contractual amount, Variable Rate	167,496	125,610
Unused Lines of Credit
Loss Contingencies [Line Items]
Financial commitments, contractual amount, Fixed Rate	55,789	61,191
Financial commitments, contractual amount, Variable Rate	102,841	75,908
Commercial and Similar Letters of Credit
Loss Contingencies [Line Items]
Financial commitments, contractual amount, Fixed Rate		1,042
Financial commitments, contractual amount, Variable Rate	358
Standby Letters of Credit
Loss Contingencies [Line Items]
Financial commitments, contractual amount, Fixed Rate	2,485	2,701
Financial commitments, contractual amount, Variable Rate	$ 1,230	$ 673

Related Party Transactions - Schedule of Related Party Transactions (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Related Party Transactions [Abstract]
Beginning balance	$ 3,600	$ 2,300
New loans and advances	16,180	7,400
Repayments	(15,780)	(6,100)
Ending balance	$ 4,000	$ 3,600

Related Party Transactions - Additional Information (Details) - USD ($)	Dec. 31, 2019	Dec. 31, 2018
Executive Officers, Directors and their Related Interests
Related Party Transaction [Line Items]
Loan commitments outstanding to related parties	$ 0	$ 800,000
Principal Officers, Directors and their Affiliates
Related Party Transaction [Line Items]
Deposits from related parties	$ 84,600,000	$ 52,100,000

Stock Option Plan - Additional Information (Details) - USD ($)		12 Months Ended
	Aug. 15, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense		$ 689,000	$ 684,000	$ 779,000
Income tax benefits recognized		161,000	$ 202,000	$ 246,000
Unamortized restricted stock compensation		$ 691,000
Stock options granted		76,500	0	0
Total unrecognized compensation cost		$ 332,000
Unrecognized compensation costs, weighted-average recognition period		2 years
Option exercised of intrinsic value		$ 1,200,000	$ 13,600,000	$ 2,800,000
Total fair of share vested		$ 460,000	$ 734,000	$ 930,000
Number of nonvested stock options		76,500	62,008	163,996
Weighted average grant date fair value, nonvested stock options		$ 6.32	$ 6.48	$ 6.53
Stock options exercised, shares		200,629
Stock options exercised		$ 2,817,000	$ 9,629,000	$ 2,296,000
Restricted Stock Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period	3 years
Number of units granted	43,425	0		0
Closing price of units granted	$ 29.38
Number of units vested		14,475
Number of remaining unvested units		28,950
Weighted average grant price		$ 29.38
Intrinsic value of vested stock		$ 262,000
2017 Omnibus Stock Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock option expiration period from date of grant		10 years
Vesting period		3 years
Number of shares available for future grant		1,254,045
Maximum \| 2017 Omnibus Stock Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of option to purchase number of outstanding common stock		30.00%
Percentage of fair market value stock on date of the grant		100.00%

Stock Option Plan - Schedule of Weighted Average Assumption for Fair Value of Option Grant Estimated Using Black-Scholes Option Pricing Model (Details) - $ / shares	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2016
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Expected volatility	35.00%	35.00%
Expected term	6 years	6 years
Expected dividends	1.90%	0.00%
Risk free rate	2.66%	1.93%
Grant date fair value	$ 6.32	$ 6.76

Stock Option Plan - Summary of Stock Option Plan (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Beginning Balance, Shares	1,215,097
Granted, Shares	76,500	0	0
Exercised, Shares	(200,629)
Ending Balance, Shares	1,090,968	1,215,097
Options exercisable, Shares	1,014,468
Beginning Balance, Weighted Average Exercise Price	$ 12.83
Granted, Weighted Average Exercise Price	18.38
Exercised, Weighted Average Exercise Price	13.43
Ending Balance, Weighted Average Exercise Price	13.11	$ 12.83
Options exercisable, Weighted Average Exercise Price	$ 12.72
Ending Balance, Weighted Average Remaining Contractual Term	4 years 25 days
Options exercisable, Weighted Average Remaining Contractual Term	3 years 8 months 8 days
Ending Balance, Aggregate Intrinsic Value	$ 8,790
Options exercisable, Aggregate Intrinsic Value	$ 8,577

Regulatory Matters - Additional Information (Details) - USD ($)					12 Months Ended
	Jan. 01, 2019	Jan. 02, 2018	Jan. 01, 2017	Jan. 02, 2016	Dec. 31, 2019	Dec. 31, 2015	Jan. 01, 2015
Compliance With Regulatory Capital Requirements Under Banking Regulations [Line Items]
Common equity Tier 1 capital to risk-weighted assets ratio with minimum for capital adequacy							4.50%
Common equity Tier 1 capital to risk-weighted assets ratio with minimum for prompt corrective action purposes							6.50%
Tier 1 capital to risk-weighted assets ratio with minimum for capital adequacy							4.00%
Increased Tier 1 capital to risk-weighted assets ratio with minimum for capital adequacy							6.00%
Tier 1 capital to risk-weighted assets ratio with minimum for prompt corrective action purposes							6.00%
Increased Tier 1 capital to risk-weighted assets ratio with minimum for prompt corrective action purposes							8.00%
Capital conservation buffer	2.50%				2.50%
Capital conservation buffer annual increase percentage	0.625%	0.625%	0.625%	0.625%
Capital conservation buffer phased-in on pro rata basis period				4 years
Capital conservation buffer phased					2.50%	0.00%
Minimum
Compliance With Regulatory Capital Requirements Under Banking Regulations [Line Items]
Regulatory assets	$ 3,000,000,000
Required assets to liabilities ratio after dividend effect					125.00%

Regulatory Matters - Summary of Actual Capital Amounts and Ratios and Related Regulatory Requirements (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Jan. 01, 2015
Compliance With Regulatory Capital Requirements Under Banking Regulations [Line Items]
Tier 1 Risk-Based Capital Ratio, Minimum Required for Capital Adequacy Purposes, Ratio			4.00%
Tier 1 Risk-Based Capital Ratio, To Be Well-Capitalized Under Prompt Corrective Provisions, Ratio			6.00%
RBB Bancorp
Compliance With Regulatory Capital Requirements Under Banking Regulations [Line Items]
Tier 1 Leverage Ratio, Amount	$ 353,572	$ 321,407
Tier 1 Leverage Ratio, Ratio	12.89%	11.80%
Common Equity Tier 1 Risk-Based Capital Ratio, Amount	$ 343,899	$ 311,901
Common Equity Tier 1 Risk-Based Capital Ratio, Ratio	17.16%	15.28%
Tier 1 Risk-Based Capital Ratio, Amount	$ 353,572	$ 321,407
Tier 1 Risk-Based Capital Ratio, Ratio	17.65%	15.74%
Total Risk-Based Capital Ratio, Amount	$ 477,262	$ 443,379
Total Risk-Based Capital Ratio, Ratio	23.82%	21.71%
Royal Business Bank
Compliance With Regulatory Capital Requirements Under Banking Regulations [Line Items]
Tier 1 Leverage Ratio, Amount	$ 417,036	$ 370,304
Tier 1 Leverage Ratio, Ratio	15.23%	13.66%
Tier 1 Leverage Ratio, Minimum Required for Capital Adequacy Purposes, Amount	$ 108,150	$ 108,445
Tier 1 Leverage Ratio, Minimum Required for Capital Adequacy Purposes, Ratio	4.00%	4.00%
Tier 1 Leverage Ratio, To Be Well-Capitalized Under Prompt Corrective Provisions, Amount	$ 135,187	$ 135,556
Tier 1 Leverage Ratio, To Be Well-Capitalized Under Prompt Corrective Provisions, Ratio	5.00%	5.00%
Common Equity Tier 1 Risk-Based Capital Ratio, Amount	$ 417,036	$ 370,304
Common Equity Tier 1 Risk-Based Capital Ratio, Ratio	20.87%	18.17%
Common Equity Tier 1 Risk-Based Capital Ratio, Minimum Required for Capital Adequacy Purposes, Amount	$ 89,127	$ 91,722
Common Equity Tier 1 Risk-Based Capital Ratio, Minimum Required for Capital Adequacy Purposes, Ratio	4.50%	4.50%
Common Equity Tier 1 Risk-Based Capital Ratio, To Be Well-Capitalized Under Prompt Corrective Provisions, Amount	$ 128,739	$ 132,487
Common Equity Tier 1 Risk-Based Capital Ratio, To Be Well-Capitalized Under Prompt Corrective Provisions, Ratio	6.50%	6.50%
Tier 1 Risk-Based Capital Ratio, Amount	$ 417,036	$ 370,304
Tier 1 Risk-Based Capital Ratio, Ratio	20.87%	18.17%
Tier 1 Risk-Based Capital Ratio, Minimum Required for Capital Adequacy Purposes, Amount	$ 118,836	$ 122,296
Tier 1 Risk-Based Capital Ratio, Minimum Required for Capital Adequacy Purposes, Ratio	6.00%	6.00%
Tier 1 Risk-Based Capital Ratio, To Be Well-Capitalized Under Prompt Corrective Provisions, Amount	$ 158,448	$ 163,061
Tier 1 Risk-Based Capital Ratio, To Be Well-Capitalized Under Prompt Corrective Provisions, Ratio	8.00%	8.00%
Total Risk-Based Capital Ratio, Amount	$ 436,677	$ 388,569
Total Risk-Based Capital Ratio, Ratio	21.86%	19.07%
Total Risk-Based Capital Ratio, Minimum Required for Capital Adequacy Purposes, Amount	$ 158,448	$ 163,061
Total Risk-Based Capital Ratio, Minimum Required for Capital Adequacy Purposes, Ratio	8.00%	8.00%
Total Risk-Based Capital Ratio, To Be Well-Capitalized Under Prompt Corrective Provisions, Amount	$ 198,061	$ 203,826
Total Risk-Based Capital Ratio, To Be Well-Capitalized Under Prompt Corrective Provisions, Ratio	10.00%	10.00%

Fair Value Measurements - Schedule of Hierarchy and Fair Value for Each Major Category of Assets and Liabilities Measured at Fair Value (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Fair Value Measurements, Recurring Basis
Assets measured at fair value:
Assets measured at fair value	$ 126,069	$ 73,762
Fair Value Measurements, Recurring Basis \| Government Agency Securities
Assets measured at fair value:
Assets measured at fair value	1,572	1,815
Fair Value Measurements, Recurring Basis \| SBA Agency Securities
Assets measured at fair value:
Assets measured at fair value	4,691	5,169
Fair Value Measurements, Recurring Basis \| Mortgage-Backed Securities
Assets measured at fair value:
Assets measured at fair value	19,171	22,541
Fair Value Measurements, Recurring Basis \| Collateralized Mortgage Obligations
Assets measured at fair value:
Assets measured at fair value	11,654	12,066
Fair Value Measurements, Recurring Basis \| Commercial Paper
Assets measured at fair value:
Assets measured at fair value	69,898	14,918
Fair Value Measurements, Recurring Basis \| Corporate Debt Securities
Assets measured at fair value:
Assets measured at fair value	19,083	17,253
Fair Value Measurements, Nonrecurring Basis
Assets measured at fair value:
Assets measured at fair value	293	1,224
Fair Value Measurements, Nonrecurring Basis \| Commercial Real Estate \| Collateral Dependent Impaired Loans
Assets measured at fair value:
Assets measured at fair value		123
Fair Value Measurements, Nonrecurring Basis \| Other Real Estate Owned
Assets measured at fair value:
Assets measured at fair value	293	1,101
Fair Value Measurements Using Level 2 \| Fair Value Measurements, Recurring Basis
Assets measured at fair value:
Assets measured at fair value	126,069	73,762
Fair Value Measurements Using Level 2 \| Fair Value Measurements, Recurring Basis \| Government Agency Securities
Assets measured at fair value:
Assets measured at fair value	1,572	1,815
Fair Value Measurements Using Level 2 \| Fair Value Measurements, Recurring Basis \| SBA Agency Securities
Assets measured at fair value:
Assets measured at fair value	4,691	5,169
Fair Value Measurements Using Level 2 \| Fair Value Measurements, Recurring Basis \| Mortgage-Backed Securities
Assets measured at fair value:
Assets measured at fair value	19,171	22,541
Fair Value Measurements Using Level 2 \| Fair Value Measurements, Recurring Basis \| Collateralized Mortgage Obligations
Assets measured at fair value:
Assets measured at fair value	11,654	12,066
Fair Value Measurements Using Level 2 \| Fair Value Measurements, Recurring Basis \| Commercial Paper
Assets measured at fair value:
Assets measured at fair value	69,898	14,918
Fair Value Measurements Using Level 2 \| Fair Value Measurements, Recurring Basis \| Corporate Debt Securities
Assets measured at fair value:
Assets measured at fair value	19,083	17,253
Fair Value Measurements Using Level 3 \| Fair Value Measurements, Nonrecurring Basis
Assets measured at fair value:
Assets measured at fair value	293	1,224
Fair Value Measurements Using Level 3 \| Fair Value Measurements, Nonrecurring Basis \| Commercial Real Estate \| Collateral Dependent Impaired Loans
Assets measured at fair value:
Assets measured at fair value		123
Fair Value Measurements Using Level 3 \| Fair Value Measurements, Nonrecurring Basis \| Other Real Estate Owned
Assets measured at fair value:
Assets measured at fair value	$ 293	$ 1,101

Fair Value Measurements - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Fair Value Disclosures [Abstract]
Write-downs to OREO	$ 0	$ 0

Fair Value Measurements - Summary of Quantitative Information About Non-recurring Level 3 Fair Value Measurements (Details) $ in Thousands	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Fair Value Measurements, Nonrecurring Basis
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured at fair value	$ 293	$ 1,224
Fair Value Measurements, Nonrecurring Basis \| Other Real Estate Owned
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured at fair value	293	1,101
Fair Value Measurements Using Level 3 \| Fair Value Measurements, Nonrecurring Basis
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured at fair value	293	1,224
Fair Value Measurements Using Level 3 \| Fair Value Measurements, Nonrecurring Basis \| Other Real Estate Owned
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured at fair value	$ 293	$ 1,101
Fair Value Measurements Using Level 3 \| Third Party Appraisals \| Other Real Estate Owned \| Measurement Input, Comparability Adjustment
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair Value Adjustment	29	16
Fair Value Measurements Using Level 3 \| Third Party Appraisals \| Other Real Estate Owned \| Measurement Input, Comparability Adjustment \| Weighted Average
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair Value Adjustment	29	16
Fair Value Measurements Using Level 3 \| Third Party Appraisals \| Fair Value Measurements, Nonrecurring Basis \| Other Real Estate Owned
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured at fair value	$ 293	$ 1,101

Fair Value of Financial Instruments - Schedule of Fair Value Hierarchy Level and Estimated Fair Value of Significant Financial Instruments (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Financial Assets:
Investment securities - AFS	$ 126,069	$ 73,762
Investment securities - HTM	8,632	9,940
Carrying Value
Financial Assets:
Cash and due from banks	114,763	147,685
Federal funds sold and other cash equivalents	67,000
Interest-earning deposits in other financial institutions	600	600
Investment securities - AFS	126,069	73,762
Investment securities - HTM	8,332	9,961
Mortgage loans held for sale	108,194	434,522
Loans, net	2,178,118	2,124,438
Equity securities	11,826	10,039
Mortgage servicing rights	17,083	17,370
Financial Liabilities:
Deposits	2,248,938	2,144,041
FHLB advances		319,500
Long-term debt	104,049	103,708
Subordinated debenture liability	9,673	9,506
Fair Value \| Fair Value, Inputs, Level 1
Financial Assets:
Cash and due from banks	114,763	147,685
Federal funds sold and other cash equivalents	67,000
Interest-earning deposits in other financial institutions	600	600
Mortgage loans held for sale	109,385	438,948
Fair Value \| Fair Value Measurements Using Level 2
Financial Assets:
Investment securities - AFS	126,069	73,762
Investment securities - HTM	8,632	9,940
Mortgage servicing rights	20,752	21,361
Financial Liabilities:
Deposits	2,236,329	2,143,196
FHLB advances		319,500
Long-term debt	109,877	79,756
Fair Value \| Fair Value Measurements Using Level 3
Financial Assets:
Loans, net	2,158,970	2,114,341
Equity securities	11,826	10,039
Financial Liabilities:
Subordinated debenture liability	$ 11,709	$ 10,356

Earnings Per Share ("EPS") - Computation of Basic and Diluted Earnings Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Earnings Per Share [Abstract]
Net income as reported	$ 10,675	$ 8,012	$ 10,142	$ 10,380	$ 9,490	$ 8,331	$ 9,437	$ 8,847	$ 39,209	$ 36,105	$ 25,528
Less: Earnings allocated to Participating Securities									$ (74)
Shares outstanding									20,030,866	20,000,022	15,908,893
Impact of weighting shares									(13,560)	(2,848,800)	(1,830,612)
Used in basic EPS, Income									$ 39,135	$ 36,105	$ 25,528
Used in basic EPS, Shares									20,017,306	17,151,222	14,078,281
Dilutive effect of outstanding
Stock options, Shares									376,118	816,431	1,160,084
Used in dilutive EPS, Income									$ 39,135	$ 36,105	$ 25,528
Used in dilutive EPS, Shares									20,393,424	17,967,653	15,238,365
Basic earnings per common share	$ 0.53	$ 0.40	$ 0.51	$ 0.52	$ 0.48	$ 0.50	$ 0.58	$ 0.55	$ 1.96	$ 2.11	$ 1.81
Diluted earnings per common share	$ 0.52	$ 0.39	$ 0.50	$ 0.51	$ 0.47	$ 0.48	$ 0.54	$ 0.52	$ 1.92	$ 2.01	$ 1.68

Earnings Per Share ("EPS") - Additional Information (Details) - shares	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Stock options \| Common Stock
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Excluded common stock for computation of diluted earnings per share	76,500	399,000	0

Revenue From Contracts With Customers - Additional Information (Details)	Jan. 01, 2019 USD ($)
ASU 2014-09
Disaggregation Of Revenue [Line Items]
Cumulative effect adjustment to retained earnings	$ 0

Revenue From Contracts With Customers - Summary of Revenue From Contracts With Customers in-Scope and Not in-Scope under Topic 606 (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disaggregation Of Revenue [Line Items]
Total in-scope non-interest income									$ 3,813	$ 2,547	$ 1,952
Non-interest income, not in scope									14,507	10,295	11,249
Total noninterest income	$ 5,823	$ 2,799	$ 5,496	$ 4,202	$ 5,489	$ 2,105	$ 2,793	$ 2,455	18,320	12,842	13,201
Fees and Service Charges on Deposit Accounts
Disaggregation Of Revenue [Line Items]
Total in-scope non-interest income									1,366	1,115	1,164
Other Fees
Disaggregation Of Revenue [Line Items]
Total in-scope non-interest income									1,118	723	145
Other Income
Disaggregation Of Revenue [Line Items]
Total in-scope non-interest income									1,429	$ 709	501
(Loss) Gain on Sale of OREO and Fixed Assets
Disaggregation Of Revenue [Line Items]
Total in-scope non-interest income									$ (100)		$ 142

Qualified Affordable Housing Project Investments - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Schedule Of Equity Method Investments [Line Items]
Investment for qualified affordable housing projects	$ 8,600,000	$ 9,500,000
Unfunded commitments related to the investments in qualified affordable housing projects	4,200,000	6,800,000
Amortization expense	900,000	644,000	$ 316,000
Recognized tax credits from its investment in affordable housing tax credits	1,100,000	573,000	275,000
Impairment losses	$ 0	$ 0	$ 0
Minimum
Schedule Of Equity Method Investments [Line Items]
Expected year in which commitments are fulfilled	2020
Maximum
Schedule Of Equity Method Investments [Line Items]
Expected year in which commitments are fulfilled	2027

Parent Only Condensed Financial Information - Schedule of Parent Only Condensed Statements of Financial Condition (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Assets
Cash and cash equivalents	$ 114,763	$ 147,685
Total assets	2,788,535	2,974,002
Liabilities and Shareholders’ Equity
Reserve for unfunded commitments	826	688
Long term debt	104,049	103,708
Accrued interest and other liabilities	17,359	21,938
Total liabilities	2,380,845	2,599,381
Shareholders' equity:
Common stock	290,395	288,610
Additional paid-in capital	4,938	5,659
Retained earnings	112,046	81,618
Non-controlling interest	72	72
Accumulated other comprehensive income (loss)	239	(1,338)
Total shareholders’ equity	407,690	374,621	$ 265,176	$ 181,585
Total liabilities and shareholders’ equity	2,788,535	2,974,002
RBB Bancorp
Assets
Cash and cash equivalents	29,985	45,540
Other assets	4,202	2,820
Total assets	521,760	488,179
Liabilities and Shareholders’ Equity
Long term debt	104,049	103,708
Subordinated debentures	9,673	9,506
Other liabilities	348	344
Total liabilities	114,070	113,558
Shareholders' equity:
Common stock	290,395	288,610
Additional paid-in capital	4,938	5,659
Retained earnings	112,046	81,618
Non-controlling interest	72	72
Accumulated other comprehensive income (loss)	239	(1,338)
Total shareholders’ equity	407,690	374,621
Total liabilities and shareholders’ equity	521,760	488,179
RBB Bancorp \| Royal Business Bank
Assets
Investment	480,703	433,023
RBB Bancorp \| Royal Asset Management
Assets
Investment	$ 6,870	$ 6,796

Parent Only Condensed Financial Information - Schedule of Parent Only Condensed Statements of Income (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Consolidated Statements of Income and Comprehensive Income
Interest income	$ 33,907	$ 34,669	$ 35,943	$ 37,206	$ 35,181	$ 24,473	$ 22,284	$ 20,177	$ 141,725	$ 102,115	$ 74,104
Interest expense	10,784	11,157	11,626	11,294	9,599	5,857	4,457	3,732	44,861	23,645	13,938
Noninterest expense	13,463	13,786	14,899	15,325	15,503	8,654	8,191	8,289	57,473	40,637	27,623
Income before income taxes	14,824	11,701	14,557	14,239	13,678	10,372	11,729	10,427	55,321	46,206	46,797
Income tax benefit	(4,149)	(3,689)	(4,415)	(3,859)	(4,188)	(2,041)	(2,292)	(1,580)	(16,112)	(10,101)	(21,269)
Net income	$ 10,675	$ 8,012	$ 10,142	$ 10,380	$ 9,490	$ 8,331	$ 9,437	$ 8,847	39,209	36,105	25,528
Other comprehensive income (loss)									1,577	(895)	(104)
Total comprehensive income									40,786	35,210	25,424
RBB Bancorp
Consolidated Statements of Income and Comprehensive Income
Interest income										15
Interest expense									7,697	4,083	3,629
Noninterest expense									1,300	1,255	642
Loss before equity in undistributed income of subsidiaries									(8,997)	(5,323)	(4,271)
Income before income taxes									36,401	34,403	23,492
Income tax benefit									2,808	1,702	2,036
Net income									39,209	36,105	25,528
Other comprehensive income (loss)									1,577	(895)	(104)
Total comprehensive income									40,786	35,210	25,424
RBB Bancorp \| Royal Business Bank
Consolidated Statements of Income and Comprehensive Income
Equity in undistributed income									45,324	39,198	27,620
RBB Bancorp \| Royal Asset Management
Consolidated Statements of Income and Comprehensive Income
Equity in undistributed income									$ 74	$ 528	$ 143

Parent Only Condensed Financial Information - Schedule of Parent Only Condensed Statements of Cash Flows (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Cash flows from operating activities:
Net income	$ 39,209	$ 36,105	$ 25,528
Net cash provided by (used in) operating activities	476,468	(84,648)	28,783
Cash flows from investment activities:
Net cash acquired (outlay) in connection with acquisition		25,073
Net cash used in investing activities	(219,353)	(322,390)	(264,446)
Cash flows from financing activities:
Issuance of subordinated debentures, net of issuance costs		54,018
Issuance of common stock, net of issuance costs			60,210
Dividends paid	(8,033)	(5,753)	(5,118)
Common stock repurchased, net of repurchased costs	(3,190)
Stock options exercised	2,817	9,629	2,296
Net cash (used in) provided by financing activities	(223,037)	404,675	266,998
Net increase (decrease) in cash and cash equivalents	34,078	(2,363)	31,335
Cash and cash equivalents at beginning of period	147,685	150,048	118,713
Cash and cash equivalents at end of period	181,763	147,685	150,048
RBB Bancorp
Cash flows from operating activities:
Net income	39,209	36,105	25,528
Net amortization of other	508	268	235
Provision for deferred income taxes	513	(1,905)	1,807
Undistributed income of subsidiaries	(45,398)	(39,726)	(27,763)
Change in other assets and liabilities	(1,981)	3,492	(3,923)
Net cash provided by (used in) operating activities	(7,149)	(1,766)	(4,116)
Cash flows from investment activities:
Net cash acquired (outlay) in connection with acquisition		(41,358)
Investment in subsidiaries		(15,000)	(25,000)
Net cash used in investing activities		(56,358)	(25,000)
Cash flows from financing activities:
Issuance of subordinated debentures, net of issuance costs		54,018
Issuance of common stock, net of issuance costs			60,210
Dividends paid	(8,033)	(5,753)	(5,118)
Common stock repurchased, net of repurchased costs	(3,190)
Stock options exercised	2,817	9,630	2,296
Net cash (used in) provided by financing activities	(8,406)	57,895	57,388
Net increase (decrease) in cash and cash equivalents	(15,555)	(229)	28,272
Cash and cash equivalents at beginning of period	45,540	45,769	17,497
Cash and cash equivalents at end of period	$ 29,985	$ 45,540	$ 45,769

Subsequent Events - Additional Information (Details) - Subsequent Event - PGB $ in Millions	Jan. 10, 2020 USD ($) Branch
Subsequent Event [Line Items]
Business acquisition, date	Jan. 10, 2020
Cash consideration	$ 32.9
Illinois
Subsequent Event [Line Items]
Business Combination, Identifiable assets acquired	217.6
Deposits	$ 192.3
Number of branches \| Branch	3

Quarterly Income Statements (Unaudited) - Schedule of Quarterly Condensed Income Statements (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Quarterly Financial Information Disclosure [Abstract]
Interest income	$ 33,907	$ 34,669	$ 35,943	$ 37,206	$ 35,181	$ 24,473	$ 22,284	$ 20,177	$ 141,725	$ 102,115	$ 74,104
Interest expense	10,784	11,157	11,626	11,294	9,599	5,857	4,457	3,732	44,861	23,645	13,938
Net interest income	23,123	23,512	24,317	25,912	25,582	18,616	17,827	16,445	96,864	78,470	60,166
Provision for credit losses	659	824	357	550	1,890	1,695	700	184	2,390	4,469	(1,053)
Net interest income after provision (recapture) for credit losses	22,464	22,688	23,960	25,362	23,692	16,921	17,127	16,261	94,474	74,001	61,219
Noninterest income:	5,823	2,799	5,496	4,202	5,489	2,105	2,793	2,455	18,320	12,842	13,201
Noninterest expense	13,463	13,786	14,899	15,325	15,503	8,654	8,191	8,289	57,473	40,637	27,623
Income before income taxes	14,824	11,701	14,557	14,239	13,678	10,372	11,729	10,427	55,321	46,206	46,797
Income tax expense	4,149	3,689	4,415	3,859	4,188	2,041	2,292	1,580	16,112	10,101	21,269
Net income	$ 10,675	$ 8,012	$ 10,142	$ 10,380	$ 9,490	$ 8,331	$ 9,437	$ 8,847	$ 39,209	$ 36,105	$ 25,528
Net income per share
Basic	$ 0.53	$ 0.40	$ 0.51	$ 0.52	$ 0.48	$ 0.50	$ 0.58	$ 0.55	$ 1.96	$ 2.11	$ 1.81
Diluted	$ 0.52	$ 0.39	$ 0.50	$ 0.51	$ 0.47	$ 0.48	$ 0.54	$ 0.52	$ 1.92	$ 2.01	$ 1.68

Repurchase of Common Stock - Additional Information (Details)	12 Months Ended
	Dec. 31, 2019 $ / shares shares
Equity [Abstract]
Number of shares authorized to be repurchased	1,000,000,000,000
Number of shares repurchased during period	169,785
Share repurchased average price per share \| $ / shares	$ 18.79