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Loans Receivable and Allowance for Loan Losses - Summary of loan portfolio (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Jun. 30, 2022	Dec. 31, 2021	Sep. 30, 2021	Jun. 30, 2021	Dec. 31, 2020
Loans and Leases Receivable Disclosure
Total loans	$ 2,286,793		$ 1,894,881
Allowance for loan losses	(18,167)	$ (15,773)	(16,902)	$ (16,803)	$ (16,672)	$ (21,009)
Deferred loan origination fees, net	(5,194)		(2,812)
Loans receivable, net	2,263,432		1,875,167
Real estate loan
Loans and Leases Receivable Disclosure
Total loans	1,826,947		1,535,037
Residential
Loans and Leases Receivable Disclosure
Total loans	61,664		79,987
Allowance for loan losses	(172)	(331)	(504)	(476)	(318)	(610)
Commercial
Loans and Leases Receivable Disclosure
Total loans	1,647,928		1,356,709
Allowance for loan losses	(12,926)	(11,480)	(12,751)	(13,246)	(13,209)	(16,425)
Construction
Loans and Leases Receivable Disclosure
Total loans	117,355		98,341
Allowance for loan losses	(133)	(95)	(4)	(142)	(133)	(221)
Commercial business
Loans and Leases Receivable Disclosure
Total loans	443,288		350,975
Allowance for loan losses	(4,808)	(3,802)	(3,590)	(2,903)	(2,976)	(3,753)
Commercial business \| PPP loans
Loans and Leases Receivable Disclosure
Total loans	36		200
Consumer
Loans and Leases Receivable Disclosure
Total loans	16,558		8,869
Allowance for loan losses	$ (128)	$ (65)	$ (53)	$ (36)	$ (36)	$ 0