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Fair Value of Assets and Liabilities - Valuation Technique (Details) $ in Thousands | 3 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | ---
Mar. 31, 2024 USD ($) item | Dec. 31, 2023 USD ($) | Mar. 31, 2023 USD ($) | Dec. 31, 2022 USD ($)
Valuation techniques and significant unobservable inputs |  |  |  |
Servicing rights | $ 2,083 | $ 2,062 | $ 2,236 | $ 2,314
Level 3 | Impaired loans | Appraisal value | Property specific adjustment |  |  |  |
Valuation techniques and significant unobservable inputs |  |  |  |
Individually evaluated | $ 4,033 | $ 3,998 |  |
Impaired Loans, Measurement Input | 0.100 | 0.100 |  |
Level 3 | Impaired loans | Appraisal value | Property specific adjustment | Weighted average |  |  |  |
Valuation techniques and significant unobservable inputs |  |  |  |
Impaired Loans, Measurement Input | 0.100 | 0.100 |  |
Level 3 | Foreclosed assets | Appraisal value | Property specific adjustment |  |  |  |
Valuation techniques and significant unobservable inputs |  |  |  |
Foreclosed assets | $ 3 | $ 32 |  |
Discount taken on Foreclosed assets balances | $ 0 | $ 0 |  |
Level 3 | Servicing rights |  |  |  |
Valuation techniques and significant unobservable inputs |  |  |  |
Servicing Asset, Valuation Technique [Extensible List] | us-gaap:ValuationTechniqueDiscountedCashFlowMember | us-gaap:ValuationTechniqueDiscountedCashFlowMember |  |
Level 3 | Servicing rights | Prepayment speed assumptions |  |  |  |
Valuation techniques and significant unobservable inputs |  |  |  |
Servicing rights | $ 1,983 | $ 2,052 |  |
Level 3 | Servicing rights | Prepayment speed assumptions | Minimum |  |  |  |
Valuation techniques and significant unobservable inputs |  |  |  |
Servicing Asset, Measurement Input | 82 | 85 |  |
Level 3 | Servicing rights | Prepayment speed assumptions | Maximum |  |  |  |
Valuation techniques and significant unobservable inputs |  |  |  |
Servicing Asset, Measurement Input | 172 | 151 |  |
Level 3 | Servicing rights | Prepayment speed assumptions | Weighted average |  |  |  |
Valuation techniques and significant unobservable inputs |  |  |  |
Servicing Asset, Measurement Input | 103 | 104 |  |
Level 3 | Servicing rights | Discount rate |  |  |  |
Valuation techniques and significant unobservable inputs |  |  |  |
Servicing Asset, Measurement Input | 0.111 | 0.111 |  |
Level 3 | Servicing rights | Discount rate | Weighted average |  |  |  |
Valuation techniques and significant unobservable inputs |  |  |  |
Servicing Asset, Measurement Input | 0.111 | 0.111 |  |

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