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Loans and Allowance for Credit Losses on Loans - Schedule of Composition of Loan Portfolio (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Jun. 30, 2023	Jan. 01, 2023	Dec. 31, 2022	Sep. 30, 2022	Jun. 30, 2022	Dec. 31, 2021
Loans And Leases Receivable Disclosure [Line Items]
Gross loans receivable	$ 1,759,525			$ 1,678,292
Allowance for credit losses	(21,617)	$ (20,802)	$ (21,165)	(19,241)	$ (18,369)	$ (17,702)	$ (16,123)
Loans receivable, net	1,737,908			1,659,051
Deferred loan fees, unamortized premiums and unaccreted (discounts)	314			160
Real Estate \| Commercial real estate
Loans And Leases Receivable Disclosure [Line Items]
Gross loans receivable	878,824			842,208
Allowance for credit losses			(7,826)
Real Estate \| SBA—real estate
Loans And Leases Receivable Disclosure [Line Items]
Gross loans receivable	225,579			221,340
Allowance for credit losses			(1,369)
SBA—non-real estate
Loans And Leases Receivable Disclosure [Line Items]
Gross loans receivable	14,575			13,377
Allowance for credit losses	(150)	(55)	(65)	(207)	(147)	(135)	(199)
C&I
Loans And Leases Receivable Disclosure [Line Items]
Gross loans receivable	124,632			116,951
Allowance for credit losses	(1,155)	(1,270)	(1,323)	(1,643)	(2,393)	(2,102)	(2,848)
Home mortgage
Loans And Leases Receivable Disclosure [Line Items]
Gross loans receivable	515,789			482,949
Allowance for credit losses	(11,597)	(11,472)	(10,579)	(8,826)	(7,434)	(5,913)	(2,891)
Consumer
Loans And Leases Receivable Disclosure [Line Items]
Gross loans receivable	126			1,467
Allowance for credit losses	$ 0	$ (3)	$ (3)	$ (7)	$ (8)	$ (9)	$ (13)