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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, 2024 USD ($) loans loan | Sep. 30, 2023 USD ($) | Sep. 30, 2024 USD ($) loans loan | Sep. 30, 2023 USD ($) | Dec. 31, 2023 USD ($)
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |
Mortgage Loans in Process of Foreclosure, Amount | $ 0 |  | $ 0 |  | $ 1,000
Reversal of interest income on nonaccrual loans | 13 | $ 13 | 75 | $ 78 |
Nonaccrual loans, no allowance | 4,500 |  | 4,500 |  | 1,000
Collateral-dependent loans | $ 11,500 |  | $ 11,500 |  | 7,500
Number of loans modified, nonaccrual | loans | 3 |  | 3 |  |
Modified in period, amount |  |  | $ 362 |  | 506
Restructured loans in default |  |  | 289 | 0 |
Accrued interest receivable on our loan portfolio | $ 21,300 |  | 21,300 |  | $ 21,300
Extended Maturity |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |
Modified in period, amount | 25 |  | $ 25 |  |
Commercial Real Estate Loans |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |
General Loan Term |  |  | 20 years |  |
Owner and nonowner-occupied real estate | 1,850,000 |  | $ 1,850,000 |  |
Loans secured by multi-family properties | 547,700 |  | 547,700 |  |
Loans secured by farmland | $ 27,700 |  | $ 27,700 |  |
Commercial loans | Commercial Portfolio Segment |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |
Modified in period, amount |  |  |  | $ 358 |
Number of loans modified |  |  |  | 4 |
Commercial loans | Extended Maturity |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |
Number of loans modified, nonaccrual | loan | 1 |  | 1 |  |
Commercial loans | Extended Maturity | Commercial Portfolio Segment |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |
Modified in period, amount |  |  |  | $ 293 |
Commercial loans | Extended Maturity and Interest Rate Reduction | Commercial Portfolio Segment |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |
Modified in period, amount |  |  |  | $ 65 |
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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