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Loans and Allowance for Loan Losses - Composition of Loan Portfolio (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Loans And Leases Receivable Disclosure [Line Items]
Gross loans receivable	$ 1,314,019	$ 1,099,736
Allowance for loan losses	(16,123)	(15,352)	$ (10,050)	$ (9,636)
Loans receivable, net	1,297,896	1,084,384
Deferred loan fees, unamortized premiums and unaccreted discounts	7,000	5,900
Real Estate \| Commercial real estate
Loans And Leases Receivable Disclosure [Line Items]
Gross loans receivable	701,450	651,684
Real Estate \| SBA Loans—Real Estate
Loans And Leases Receivable Disclosure [Line Items]
Gross loans receivable	220,099	136,224
SBA loans—non-real estate
Loans And Leases Receivable Disclosure [Line Items]
Gross loans receivable	55,759	75,151
Allowance for loan losses	(199)	(278)	(121)	(505)
SBA loans—non-real estate \| PPP loans
Loans And Leases Receivable Disclosure [Line Items]
Loans receivable, net	40,600	64,900
Commercial and industrial ("C&I")
Loans And Leases Receivable Disclosure [Line Items]
Gross loans receivable	162,543	107,307
Allowance for loan losses	(2,848)	(2,563)	(1,289)	(1,746)
Home mortgage
Loans And Leases Receivable Disclosure [Line Items]
Gross loans receivable	173,303	128,212
Allowance for loan losses	(2,891)	(2,185)	(1,667)	(1,653)
Consumer
Loans And Leases Receivable Disclosure [Line Items]
Gross loans receivable	865	1,158
Allowance for loan losses	$ (13)	$ (19)	$ (34)	$ (33)