Loans and Allowance for Loan Losses - Schedule of Activity in Allowance for Loan Losses by Portfolio Segment (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Analysis of allowance for loan losses
Beginning balance	$ 16,672,000	$ 15,339,000	$ 16,123,000	$ 15,352,000
Provision for (reversal of) loan losses	996,000	(625,000)	1,541,000	(641,000)
Charge-offs	(18,000)	(27,000)	(32,000)	(27,000)
Recoveries	52,000	0	70,000	3,000
Ending balance	17,702,000	14,687,000	17,702,000	14,687,000
Provision for (reversal of) loan losses	996,000	(1,112,000)	1,337,000	(492,000)
Uncollectible Accrued Interest Receivable
Analysis of allowance for loan losses
Provision for (reversal of) loan losses	0	(487,000)	(204,000)	149,000
Commercial real estate
Analysis of allowance for loan losses
Beginning balance	6,480,000	8,594,000	8,150,000	8,505,000
Provision for (reversal of) loan losses	1,263,000	(138,000)	(407,000)	(49,000)
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Ending balance	7,743,000	8,456,000	7,743,000	8,456,000
SBA loans—real estate
Analysis of allowance for loan losses
Beginning balance	1,750,000	2,030,000	2,022,000	1,802,000
Provision for (reversal of) loan losses	43,000	(33,000)	(215,000)	195,000
Charge-offs	0	0	(14,000)	0
Recoveries	7,000	0	7,000	0
Ending balance	1,800,000	1,997,000	1,800,000	1,997,000
SBA loans—non-real estate
Analysis of allowance for loan losses
Beginning balance	169,000	292,000	199,000	278,000
Provision for (reversal of) loan losses	(61,000)	(37,000)	(108,000)	(23,000)
Charge-offs	(18,000)	(27,000)	(18,000)	(27,000)
Recoveries	45,000	0	62,000	0
Ending balance	135,000	228,000	135,000	228,000
Commercial and industrial ("C&I")
Analysis of allowance for loan losses
Beginning balance	3,492,000	2,331,000	2,848,000	2,563,000
Provision for (reversal of) loan losses	(1,390,000)	(45,000)	(746,000)	(277,000)
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Ending balance	2,102,000	2,286,000	2,102,000	2,286,000
Home mortgage
Analysis of allowance for loan losses
Beginning balance	4,768,000	2,075,000	2,891,000	2,185,000
Provision for (reversal of) loan losses	1,145,000	(371,000)	3,022,000	(481,000)
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Ending balance	5,913,000	1,704,000	5,913,000	1,704,000
Consumer
Analysis of allowance for loan losses
Beginning balance	13,000	17,000	13,000	19,000
Provision for (reversal of) loan losses	(4,000)	(1,000)	(5,000)	(6,000)
Charge-offs	0	0	0	0
Recoveries	0	0	1,000	3,000
Ending balance	$ 9,000	$ 16,000	$ 9,000	$ 16,000