Fair Value Measurement - Fair Values and Carrying Amounts, Significant Financial Instruments (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Interest bearing deposits in banks	$ 14,192	$ 13,196
Loans held for sale	2,349	13,829
Deposits
Noninterest bearing	303,077	264,888
Interest bearing	726,864	723,479
Time	104,303	106,715
Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	50,802	65,922
Interest bearing deposits in banks	0	0
Investment securities	3,984	4,007
Loans held for sale	0	0
Accrued interest receivable	0	0
Deposits
Noninterest bearing	303,077	264,888
Interest bearing	726,864	723,479
Time	0	0
Borrowed funds
Subordinated notes	0	0
Accrued interest payable	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) | Residential real estate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans, net	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) | Construction real estate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans, net	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) | Commercial real estate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans, net	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) | Commercial
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans, net	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) | Consumer
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans, net	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) | Municipal
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans, net	0	0
Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	0	0
Interest bearing deposits in banks	14,192	13,196
Investment securities	269,440	264,944
Loans held for sale	2,398	14,088
Accrued interest receivable	837	734
Deposits
Noninterest bearing	0	0
Interest bearing	0	0
Time	103,028	106,588
Borrowed funds
Subordinated notes	15,448	16,179
Accrued interest payable	76	225
Significant Other Observable Inputs (Level 2) | Residential real estate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans, net	0	0
Significant Other Observable Inputs (Level 2) | Construction real estate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans, net	0	0
Significant Other Observable Inputs (Level 2) | Commercial real estate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans, net	0	0
Significant Other Observable Inputs (Level 2) | Commercial
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans, net	0	0
Significant Other Observable Inputs (Level 2) | Consumer
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans, net	0	0
Significant Other Observable Inputs (Level 2) | Municipal
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans, net	0	0
Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	0	0
Interest bearing deposits in banks	0	0
Investment securities	0	0
Loans held for sale	0	0
Accrued interest receivable	2,411	2,514
Deposits
Noninterest bearing	0	0
Interest bearing	0	0
Time	0	0
Borrowed funds
Subordinated notes	0	0
Accrued interest payable	0	0
Significant Unobservable Inputs (Level 3) | Residential real estate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans, net	271,384	246,573
Significant Unobservable Inputs (Level 3) | Construction real estate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans, net	68,104	64,539
Significant Unobservable Inputs (Level 3) | Commercial real estate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans, net	345,769	341,451
Significant Unobservable Inputs (Level 3) | Commercial
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans, net	43,754	48,682
Significant Unobservable Inputs (Level 3) | Consumer
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans, net	2,222	2,350
Significant Unobservable Inputs (Level 3) | Municipal
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans, net	81,782	78,748
Carrying Amount
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	50,802	65,922
Interest bearing deposits in banks	14,192	13,196
Investment securities	273,424	268,951
Loans held for sale	2,349	13,829
Accrued interest receivable	3,248	3,248
Nonmarketable equity securities	1,164	1,164
Deposits
Noninterest bearing	303,077	264,888
Interest bearing	726,864	723,479
Time	104,303	106,715
Borrowed funds
Subordinated notes	16,179	16,171
Accrued interest payable	76	225
Carrying Amount | Residential real estate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans, net	280,781	244,980
Carrying Amount | Construction real estate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans, net	67,971	64,370
Carrying Amount | Commercial real estate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans, net	343,920	340,066
Carrying Amount | Commercial
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans, net	44,574	49,558
Carrying Amount | Consumer
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans, net	2,234	2,367
Carrying Amount | Municipal
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans, net	80,798	78,078
Estimated Fair Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	50,802	65,922
Interest bearing deposits in banks	14,192	13,196
Investment securities	273,424	268,951
Loans held for sale	2,398	14,088
Accrued interest receivable	3,248	3,248
Deposits
Noninterest bearing	303,077	264,888
Interest bearing	726,864	723,479
Time	103,028	106,588
Borrowed funds
Subordinated notes	15,448	16,179
Accrued interest payable	76	225
Estimated Fair Value | Residential real estate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans, net	271,384	246,573
Estimated Fair Value | Construction real estate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans, net	68,104	64,539
Estimated Fair Value | Commercial real estate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans, net	345,769	341,451
Estimated Fair Value | Commercial
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans, net	43,754	48,682
Estimated Fair Value | Consumer
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans, net	2,222	2,350
Estimated Fair Value | Municipal
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans, net	$ 81,782	$ 78,748