Loans and Allowance for Credit Losses - Loans - Major Categories of Loans (Details) - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Loans and Allowance for Credit Losses - Loans
Loans, net of deferred fees and costs	$ 176,307,000	$ 186,440,000
Less: Allowance for credit losses	(2,157,000)	(2,162,000)	$ (2,470,000)
Loans, net	174,150,000	184,278,000
Increase (decrease) in loans and leases receivable	$ 10,100,000
Percentage of increase (decrease) in loans and leases receivable	5.50%
Related party loans	$ 150,000	0
Real Estate Loan
Loans and Allowance for Credit Losses - Loans
Loans, net of deferred fees and costs	136,230,000	133,323,000
Commercial and Industrial
Loans and Allowance for Credit Losses - Loans
Loans, net of deferred fees and costs	16,774,000	15,148,000
Consumer Loans
Loans and Allowance for Credit Losses - Loans
Loans, net of deferred fees and costs	23,303,000	37,969,000
Construction and Land | Real Estate Loan
Loans and Allowance for Credit Losses - Loans
Loans, net of deferred fees and costs	4,636,000	4,499,000
Less: Allowance for credit losses	(31,000)	(44,000)	(5,000)
Loans, net	4,600,000	4,500,000
Increase (decrease) in loans and leases receivable	$ 100,000
Percentage of increase (decrease) in loans and leases receivable	3.04%
Farmland | Real Estate Loan
Loans and Allowance for Credit Losses - Loans
Loans, net of deferred fees and costs	$ 325,000	333,000
Less: Allowance for credit losses	(18,000)	(20,000)	(11,000)
Loans, net	300,000
Single-family Residential | Real Estate Loan
Loans and Allowance for Credit Losses - Loans
Loans, net of deferred fees and costs	86,887,000	80,251,000
Less: Allowance for credit losses	(1,290,000)	(1,230,000)	(1,357,000)
Loans, net	86,900,000	80,300,000
Increase (decrease) in loans and leases receivable	$ 6,600,000
Percentage of increase (decrease) in loans and leases receivable	8.27%
Multi-family | Real Estate Loan
Loans and Allowance for Credit Losses - Loans
Loans, net of deferred fees and costs	$ 5,165,000	5,304,000
Less: Allowance for credit losses	(96,000)	(103,000)	(105,000)
Loans, net	5,200,000	5,300,000
Increase (decrease) in loans and leases receivable	$ 100,000
Percentage of increase (decrease) in loans and leases receivable	2.62%
Commercial | Real Estate Loan
Loans and Allowance for Credit Losses - Loans
Loans, net of deferred fees and costs	$ 39,217,000	42,936,000
Less: Allowance for credit losses	(190,000)	(221,000)	(278,000)
Loans, net	39,200,000	42,900,000
Increase (decrease) in loans and leases receivable	$ 3,700,000
Percentage of increase (decrease) in loans and leases receivable	8.66%
Commercial | Commercial and Industrial
Loans and Allowance for Credit Losses - Loans
Loans, net of deferred fees and costs	$ 16,774,000	15,148,000
Commercial and industrial | Commercial and Industrial
Loans and Allowance for Credit Losses - Loans
Loans, net of deferred fees and costs	10,850,000	8,990,000
Less: Allowance for credit losses	(304,000)	(174,000)	(115,000)
Loans, net	10,900,000	9,000,000.0
Increase (decrease) in loans and leases receivable	$ 1,900,000
Percentage of increase (decrease) in loans and leases receivable	20.69%
SBA Guaranty | Commercial and Industrial
Loans and Allowance for Credit Losses - Loans
Loans, net of deferred fees and costs	$ 5,924,000	6,158,000
Less: Allowance for credit losses	(21,000)	(22,000)	(30,000)
Loans, net	5,900,000	6,200,000
Increase (decrease) in loans and leases receivable	$ 300,000
Percentage of increase (decrease) in loans and leases receivable	3.79%
Consumer
Loans and Allowance for Credit Losses - Loans
Loans, net	$ 21,300,000	36,400,000
Consumer | Consumer Loans
Loans and Allowance for Credit Losses - Loans
Loans, net of deferred fees and costs	2,039,000	1,521,000
Less: Allowance for credit losses	(30,000)	(23,000)	(36,000)
Loans, net	2,000,000.0	1,500,000
Increase (decrease) in loans and leases receivable	$ 500,000
Percentage of increase (decrease) in loans and leases receivable	34.06%
Automobile | Consumer Loans
Loans and Allowance for Credit Losses - Loans
Loans, net of deferred fees and costs	$ 21,264,000	36,448,000
Less: Allowance for credit losses	(177,000)	(325,000)	$ (533,000)
Loans, net	21,300,000	$ 36,400,000
Increase (decrease) in loans and leases receivable	$ 15,100,000
Percentage of increase (decrease) in loans and leases receivable	41.66%