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Loans Loans (Analysis of Troubled Debt Restructurings) (Details) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2020 USD ($) Modifications | Dec. 31, 2019 USD ($) Modifications | Dec. 31, 2018 USD ($) Modifications
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |
TDR Modifications, Number of Contracts | Modifications | 19 | 24 | 34
Pre-Modification Outstanding Recorded Investment | $ 7,566 | $ 7,348 | $ 22,047
Post-Modification Outstanding Recorded Investment | $ 7,566 | $ 7,348 | $ 22,047
Commercial Real Estate |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |
TDR Modifications, Number of Contracts | Modifications | 0 | 0 | 1
Pre-Modification Outstanding Recorded Investment | $ 0 | $ 0 | $ 891
Post-Modification Outstanding Recorded Investment | $ 0 | $ 0 | $ 891
Commercial Business |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |
TDR Modifications, Number of Contracts | Modifications | 11 | 10 | 10
Pre-Modification Outstanding Recorded Investment | $ 3,257 | $ 6,560 | $ 18,352
Post-Modification Outstanding Recorded Investment | $ 3,257 | $ 6,560 | $ 18,352
Agriculture |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |
TDR Modifications, Number of Contracts | Modifications | 2 | 0 | 2
Pre-Modification Outstanding Recorded Investment | $ 3,495 | $ 0 | $ 27
Post-Modification Outstanding Recorded Investment | $ 3,495 | $ 0 | $ 27
Real estate: One-to-four family residential |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |
TDR Modifications, Number of Contracts | Modifications | 6 | 13 | 21
Pre-Modification Outstanding Recorded Investment | $ 814 | $ 787 | $ 2,777
Post-Modification Outstanding Recorded Investment | $ 814 | $ 787 | $ 2,777
Consumer Loan |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |
TDR Modifications, Number of Contracts | Modifications | 0 | 1 | 0
Pre-Modification Outstanding Recorded Investment | $ 0 | $ 1 | $ 0
Post-Modification Outstanding Recorded Investment | $ 0 | $ 1 | $ 0

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