Loans and Allowance for Loan Losses - Schedule of Activity in Allowance for Loan Losses by Portfolio Segment (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Analysis of allowance for loan losses
Beginning balance	$ 14,687,000	$ 12,764,000	$ 15,352,000	$ 10,050,000
(Reversal of) provision for loan losses	(557,000)	1,399,000	(1,198,000)	4,130,000
Charge-offs	0	0	(27,000)	(45,000)
Recoveries	4,000	1,000	7,000	29,000
Ending balance	14,134,000	14,164,000	14,134,000	14,164,000
(Reversal of) provision for loan losses	(884,000)	1,399,000	(1,376,000)	4,130,000
Uncollectible Accrued Interest Receivable
Analysis of allowance for loan losses
(Reversal of) provision for loan losses	(327,000)	0	(178,000)	0
Commercial Real Estate
Analysis of allowance for loan losses
Beginning balance	8,456,000	7,145,000	8,505,000	6,000,000
(Reversal of) provision for loan losses	(241,000)	994,000	(290,000)	2,139,000
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Ending balance	8,215,000	8,139,000	8,215,000	8,139,000
SBA Loans Real Estate
Analysis of allowance for loan losses
Beginning balance	1,997,000	1,346,000	1,802,000	939,000
(Reversal of) provision for loan losses	99,000	412,000	294,000	819,000
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Ending balance	2,096,000	1,758,000	2,096,000	1,758,000
SBA Loans Non- Real Estate
Analysis of allowance for loan losses
Beginning balance	228,000	253,000	278,000	121,000
(Reversal of) provision for loan losses	(35,000)	18,000	(58,000)	167,000
Charge-offs	0	0	(27,000)	(45,000)
Recoveries	3,000	0	3,000	28,000
Ending balance	196,000	271,000	196,000	271,000
Commercial and Industrial
Analysis of allowance for loan losses
Beginning balance	2,286,000	1,920,000	2,563,000	1,289,000
(Reversal of) provision for loan losses	(332,000)	(5,000)	(609,000)	626,000
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Ending balance	1,954,000	1,915,000	1,954,000	1,915,000
Home Mortgage
Analysis of allowance for loan losses
Beginning balance	1,704,000	2,074,000	2,185,000	1,667,000
(Reversal of) provision for loan losses	(46,000)	(15,000)	(527,000)	392,000
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Ending balance	1,658,000	2,059,000	1,658,000	2,059,000
Consumer
Analysis of allowance for loan losses
Beginning balance	16,000	26,000	19,000	34,000
(Reversal of) provision for loan losses	(2,000)	(5,000)	(8,000)	(13,000)
Charge-offs	0	0	0	0
Recoveries	1,000	1,000	4,000	1,000
Ending balance	$ 15,000	$ 22,000	$ 15,000	$ 22,000