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Loans and ALLL (Summary of information pertaining to TDRs) (Details) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2021 USD ($) loan | Jun. 30, 2020 USD ($) loan | Jun. 30, 2021 USD ($) loan | Jun. 30, 2020 USD ($) loan
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment | $ 8,763 | $ 10,174 | $ 8,828 | $ 10,014
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method | $ 106 | $ 116 | $ 188 | $ 248
Number of Loans | loan | 2 | 2 | 11 | 8
Pre-Modification Recorded Investment | $ 109 | $ 1,768 | $ 8,473 | $ 3,417
Financing Receivable, Troubled Debt Restructuring, Postmodification | $ 109 | $ 1,768 | $ 8,473 | $ 3,417
Interest Rate Below Market Reduction [Member] |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Number of Loans | loan | 0 | 0 | 7 | 1
Pre-Modification Recorded Investment | $ 0 | $ 0 | $ 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 | 2 | 4 | 7
Pre-Modification Recorded Investment | $ 109 | $ 1,768 | $ 1,572 | $ 2,498
Commercial other [Member] |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment | 1,563 | 460 | 808 | 460
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method | $ 36 | $ 0 | $ 36 | $ 6
Number of Loans | loan | 2 | 0 | 5 | 2
Pre-Modification Recorded Investment | $ 109 | $ 0 | $ 4,761 | $ 963
Financing Receivable, Troubled Debt Restructuring, Postmodification | $ 109 | $ 0 | $ 4,761 | $ 963
Commercial other [Member] | Interest Rate Below Market Reduction [Member] |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Number of Loans | loan | 0 | 0 | 1 | 1
Pre-Modification Recorded Investment | $ 0 | $ 0 | $ 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 | 0 | 4 | 1
Pre-Modification Recorded Investment | $ 109 | $ 0 | $ 1,572 | $ 44
Agricultural other [Member] |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment | 0 | 1,355 | 339 | 1,355
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method | $ 0 | $ 20 | $ 0 | $ 42
Number of Loans | loan | 0 | 2 | 6 | 4
Pre-Modification Recorded Investment | $ 0 | $ 1,768 | $ 3,712 | $ 2,361
Financing Receivable, Troubled Debt Restructuring, Postmodification | $ 0 | $ 1,768 | $ 3,712 | $ 2,361
Agricultural other [Member] | Interest Rate Below Market Reduction [Member] |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Number of Loans | loan | 0 | 0 | 6 | 0
Pre-Modification Recorded Investment | $ 0 | $ 0 | $ 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 | 0 | 4
Pre-Modification Recorded Investment | $ 0 | $ 1,768 | $ 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 | 3,912 | 5,050 | 4,070 | 5,197
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method | $ 35 | $ 49 | $ 78 | $ 104
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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