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Fair Value of Assets and Liabilities - Valuation Technique (Details) - Level 3 | Mar. 31, 2021 USD ($) item | Dec. 31, 2020 USD ($) item
--- | --- | ---
Impaired loans | Appraisal value | Property specific adjustment |  |
Valuation techniques and significant unobservable inputs |  |
Impaired loans | $ 7,139,000 | $ 7,325,000
Foreclosed assets | Appraisal value | Property specific adjustment |  |
Valuation techniques and significant unobservable inputs |  |
Foreclosed assets | $ 139,000 | $ 63,000
Servicing rights |  |
Valuation techniques and significant unobservable inputs |  |
Servicing Asset, Valuation Technique [Extensible List] | us-gaap:ValuationTechniqueDiscountedCashFlowMember | us-gaap:ValuationTechniqueDiscountedCashFlowMember
Servicing rights | Prepayment speed assumptions |  |
Valuation techniques and significant unobservable inputs |  |
Servicing rights | $ 1,952,000 | $ 1,987,000
Servicing rights | Prepayment speed assumptions | Minimum |  |
Valuation techniques and significant unobservable inputs |  |
Servicing Asset, Measurement Input | item | 175 | 191
Servicing rights | Prepayment speed assumptions | Maximum |  |
Valuation techniques and significant unobservable inputs |  |
Servicing Asset, Measurement Input | item | 298 | 403
Servicing rights | Prepayment speed assumptions | Weighted average |  |
Valuation techniques and significant unobservable inputs |  |
Servicing Asset, Measurement Input | 269 | 285
Servicing rights | Discount rate |  |
Valuation techniques and significant unobservable inputs |  |
Servicing Asset, Measurement Input | 0.090 | 0.090
Servicing rights | Discount rate | Weighted average |  |
Valuation techniques and significant unobservable inputs |  |
Servicing Asset, Measurement Input | 0.090 | 0.090

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