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Loans and Allowance for Loan Losses - Narrative (Details) $ in Thousands | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | ---
Sep. 30, 2023 USD ($) loans | Sep. 30, 2022 USD ($) | Sep. 30, 2023 USD ($) loans | Sep. 30, 2022 USD ($) | Dec. 31, 2022 USD ($)
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |
Mortgage Loans in Process of Foreclosure, Amount | $ 63 |  | $ 63 |  | $ 0
Reversal of interest income on nonaccrual loans | 13 | $ 10 | 78 | $ 33 |
Nonaccrual loans, no allowance | 1,000 |  | 1,000 |  | 1,600
Collateral-dependent loans | 7,700 |  | 7,700 |  | 8,100
Restructured loans |  |  |  |  | 897
Accrued interest receivable on our loan portfolio | 20,300 |  | 20,300 |  | $ 18,800
Amortization Period Extension |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |
Restructured loans |  |  | $ 343 |  |
Commercial Real Estate Loans |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |
General Loan Term |  |  | 20 years |  |
Owner and nonowner-occupied real estate | 1,750,000 |  | $ 1,750,000 |  |
Loans secured by multi-family properties | 339,400 |  | 339,400 |  |
Loans secured by farmland | $ 29,400 |  | $ 29,400 |  |
Commercial loans | Amortization Period Extension |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |
Number of loans modified | loans | 3 |  | 3 |  |
Restructured loans |  |  | $ 343 |  |
1-4 Family Residential Real Estate Loans | Minimum |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |
General Loan Term |  |  | 15 years |  |
1-4 Family Residential Real Estate Loans | Maximum |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |
General Loan Term |  |  | 30 years |  |

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