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Loans and ALLL (Summary of information pertaining to TDRs) (Details) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2021 USD ($) loan | Sep. 30, 2020 USD ($) loan | Sep. 30, 2021 USD ($) loan | Sep. 30, 2020 USD ($) loan
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment | $ 8,146 | $ 10,159 | $ 8,601 | $ 10,064
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method | 75 | 143 | $ 263 | $ 391
Number of Loans | loan |  |  | 11 | 12
Pre-Modification Recorded Investment |  |  | $ 8,473 | $ 7,157
Financing Receivable, Troubled Debt Restructuring, Postmodification |  |  | $ 8,473 | $ 7,157
Interest Rate Below Market Reduction [Member] |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Number of Loans | loan |  |  | 7 | 2
Pre-Modification Recorded Investment |  |  | $ 6,901 | $ 987
Below Market Interest Rate and Extension of Amortization Period [Member] |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Number of Loans | loan |  |  | 4 | 10
Pre-Modification Recorded Investment |  |  | $ 1,572 | $ 6,170
Commercial other [Member] |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment | 3,090 | 442 | 1,569 | 454
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method | $ 35 | $ 13 | $ 71 | $ 19
Number of Loans | loan | 0 | 4 | 5 | 6
Pre-Modification Recorded Investment | $ 0 | $ 3,740 | $ 4,761 | $ 4,702
Financing Receivable, Troubled Debt Restructuring, Postmodification | $ 0 | $ 3,740 | $ 4,761 | $ 4,702
Commercial other [Member] | Interest Rate Below Market Reduction [Member] |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Number of Loans | loan | 0 | 1 | 1 | 2
Pre-Modification Recorded Investment | $ 0 | $ 68 | $ 3,189 | $ 987
Commercial other [Member] | Below Market Interest Rate and Extension of Amortization Period [Member] |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Number of Loans | loan | 0 | 3 | 4 | 4
Pre-Modification Recorded Investment | $ 0 | $ 3,672 | $ 1,572 | $ 3,715
Agricultural other [Member] |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment | 0 | 1,355 | 226 | 1,355
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method | 0 | 18 | $ 0 | $ 60
Number of Loans | loan |  |  | 6 | 4
Pre-Modification Recorded Investment |  |  | $ 3,712 | $ 2,361
Financing Receivable, Troubled Debt Restructuring, Postmodification |  |  | $ 3,712 | $ 2,361
Agricultural other [Member] | Interest Rate Below Market Reduction [Member] |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Number of Loans | loan |  |  | 6 | 0
Pre-Modification Recorded Investment |  |  | $ 3,712 | $ 0
Agricultural other [Member] | Below Market Interest Rate and Extension of Amortization Period [Member] |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Number of Loans | loan |  |  | 0 | 4
Pre-Modification Recorded Investment |  |  | $ 0 | $ 2,361
Residential real estate senior liens [Member] |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment | 3,585 | 4,600 | 3,908 | 4,998
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method | $ 37 | $ 48 | $ 115 | $ 152
Number of Loans | loan |  |  | 0 | 2
Pre-Modification Recorded Investment |  |  | $ 0 | $ 94
Financing Receivable, Troubled Debt Restructuring, Postmodification |  |  | $ 0 | $ 94
Residential real estate senior liens [Member] | Interest Rate Below Market Reduction [Member] |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Number of Loans | loan |  |  | 0 | 0
Pre-Modification Recorded Investment |  |  | $ 0 | $ 0
Residential real estate senior liens [Member] | Below Market Interest Rate and Extension of Amortization Period [Member] |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Number of Loans | loan |  |  | 0 | 2
Pre-Modification Recorded Investment |  |  | $ 0 | $ 94

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