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Fair Value of Assets and Liabilities - Significant Unobservable Inputs Used in Valuation of Level 3 Fair Value Measurements (Details) - USD ($) $ in Thousands | 9 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2021 | Dec. 31, 2020
Mortgage Servicing Rights | Minimum | Level 3 | Third Party Valuations |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] |  |
Mortgage servicing rights | 230.00% | 242.00%
Mortgage Servicing Rights | Maximum | Level 3 | Third Party Valuations |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] |  |
Mortgage servicing rights | 438.00% | 441.00%
Mortgage Servicing Rights | Weighted Average | Level 3 | Third Party Valuations |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] |  |
Mortgage servicing rights | 281.00% | 384.00%
Collateral Dependent Loans | Minimum | Level 3 | Third Party Valuations |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] |  |
Collateral dependent loans | 0.00% | 0.00%
Collateral Dependent Loans | Maximum | Level 3 | Third Party Valuations |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] |  |
Collateral dependent loans | 40.00% | 40.00%
Collateral Dependent Loans | Weighted Average | Level 3 | Third Party Valuations |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] |  |
Collateral dependent loans | 20.00% | 20.00%
Foreclosed Assets Held-for-sale | Minimum | Level 3 | Third Party Valuations |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] |  |
Collateral dependent loans | 0.00% | 0.00%
Foreclosed Assets Held-for-sale | Maximum | Level 3 | Third Party Valuations |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] |  |
Collateral dependent loans | 40.00% | 40.00%
Foreclosed Assets Held-for-sale | Weighted Average | Level 3 | Third Party Valuations |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] |  |
Collateral dependent loans | 35.00% | 35.00%
Fair Value, Nonrecurring | Mortgage Servicing Rights |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] |  |
Assets, Fair Value | $ 455 | $ 517
Fair Value, Nonrecurring | Collateral Dependent Loans |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] |  |
Assets, Fair Value | 13,682 | 14,876
Fair Value, Nonrecurring | Collateral Dependent Loans | Level 3 |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] |  |
Assets, Fair Value | 13,682 | 14,876
Fair Value, Nonrecurring | Foreclosed Assets Held-for-sale |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] |  |
Assets, Fair Value | $ 1,720 | $ 290

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- Definition Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=123874694&loc=d3e19207-110258 + Details
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