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Financial Instruments with Off-Balance Sheet Risk (Details) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Dec. 31, 2020 | Dec. 31, 2022 | Dec. 31, 2021 | Sep. 30, 2020
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Increase (decrease) in available commitments |  | $ (318) | $ (993) |
Commercial lines of credit |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Loan commitments and standby letters of credit, off-balance sheet |  | 292,204 | 330,234 |
Revolving home equity lines |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Loan commitments and standby letters of credit, off-balance sheet |  | 218,907 | 210,938 |
Undisbursed construction loans |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Loan commitments and standby letters of credit, off-balance sheet |  | 43,179 | 78,381 |
Personal and other lines of credit |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Loan commitments and standby letters of credit, off-balance sheet |  | 10,842 | 11,001 |
Standby letters of credit |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Loan commitments and standby letters of credit, off-balance sheet |  | 1,738 | 3,657 |
Total unfunded loan commitments and standby letters of credit |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Loan commitments and standby letters of credit, off-balance sheet |  | $ 566,870 | 634,211 |
Percentage of commitments expiring in 2023 |  | 42.00% |  |
Percentage of commitments expiring between 2024 and 2030 |  | 42.00% |  |
Percentage of commitments expiring 2030 and thereafter |  | 16.00% |  |
Allowance for off-balance sheet commitments |  | $ 1,500 | $ 1,800 | $ 610
Increase (decrease) in available commitments | $ 36,900 |  |  |
Total unfunded loan commitments and standby letters of credit | Cumulative Effect, Period of Adoption, Adjusted Balance |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Allowance for off-balance sheet commitments | 1,100 |  |  |
Total unfunded loan commitments and standby letters of credit | Cumulative Effect, Period of Adoption, Adjustment |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Allowance for off-balance sheet commitments | $ 550 |  |  |

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