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Loans and Allowance for Loan Losses - Composition of Loan Portfolio (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021	Mar. 31, 2021	Dec. 31, 2020
Loans And Leases Receivable Disclosure [Line Items]
Gross loans receivable	$ 1,428,410	$ 1,314,019
Allowance for loan losses	(16,672)	(16,123)	$ (15,339)	$ (15,352)
Loans receivable, net	1,411,738	1,297,896
Deferred loan fees, unamortized premiums and unaccreted discounts	4,700	7,000
Real Estate \| Commercial real estate
Loans And Leases Receivable Disclosure [Line Items]
Gross loans receivable	730,841	701,450
Real Estate \| SBA Loans—Real Estate
Loans And Leases Receivable Disclosure [Line Items]
Gross loans receivable	217,169	220,099
SBA loans—non-real estate
Loans And Leases Receivable Disclosure [Line Items]
Gross loans receivable	35,895	55,759
Allowance for loan losses	(169)	(199)	(292)	(278)
SBA loans—non-real estate \| PPP loans
Loans And Leases Receivable Disclosure [Line Items]
Loans receivable, net	22,100	40,600
Commercial and industrial ("C&I")
Loans And Leases Receivable Disclosure [Line Items]
Gross loans receivable	176,934	162,543
Allowance for loan losses	(3,492)	(2,848)	(2,331)	(2,563)
Home mortgage
Loans And Leases Receivable Disclosure [Line Items]
Gross loans receivable	266,465	173,303
Allowance for loan losses	(4,768)	(2,891)	(2,075)	(2,185)
Consumer
Loans And Leases Receivable Disclosure [Line Items]
Gross loans receivable	1,106	865
Allowance for loan losses	$ (13)	$ (13)	$ (17)	$ (19)