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Loans and ALLL (Summary of information pertaining to TDRs) (Details) $ in Thousands | 3 Months Ended
--- | ---
Mar. 31, 2021 USD ($) loan | Mar. 31, 2020 USD ($) loan
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment | $ 8,894 | $ 9,857
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method | $ 82 | $ 132
Number of Loans | loan | 9 | 6
Pre-Modification Recorded Investment | $ 8,364 | $ 1,649
Financing Receivable, Troubled Debt Restructuring, Postmodification | $ 8,364 | $ 1,649
Interest Rate Below Market Reduction [Member] |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Number of Loans | loan | 7 | 1
Pre-Modification Recorded Investment | $ 6,901 | $ 919
Below Market Interest Rate and Extension of Amortization Period [Member] |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Number of Loans | loan | 2 | 5
Pre-Modification Recorded Investment | $ 1,463 | $ 730
Commercial other [Member] |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment | 54 | 460
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method | $ 0 | $ 6
Number of Loans | loan | 3 | 2
Pre-Modification Recorded Investment | $ 4,652 | $ 963
Financing Receivable, Troubled Debt Restructuring, Postmodification | $ 4,652 | $ 963
Commercial other [Member] | Interest Rate Below Market Reduction [Member] |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Number of Loans | loan | 1 | 1
Pre-Modification Recorded Investment | $ 3,189 | $ 919
Commercial other [Member] | Below Market Interest Rate and Extension of Amortization Period [Member] |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Number of Loans | loan | 2 | 1
Pre-Modification Recorded Investment | $ 1,463 | $ 44
Agricultural other [Member] |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment | 678 | 1,355
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method | $ 0 | $ 22
Number of Loans | loan | 6 | 2
Pre-Modification Recorded Investment | $ 3,712 | $ 593
Financing Receivable, Troubled Debt Restructuring, Postmodification | $ 3,712 | $ 593
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 | 2
Pre-Modification Recorded Investment | $ 0 | $ 593
Residential real estate senior liens [Member] |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment | 4,228 | 5,343
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method | $ 43 | $ 55
Number of Loans | loan | 0 | 2
Pre-Modification Recorded Investment | $ 0 | $ 93
Financing Receivable, Troubled Debt Restructuring, Postmodification | $ 0 | $ 93
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 | $ 93

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