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Loans and ALLL (Summary of information pertaining to impaired loans) (Details) - USD ($) $ in Thousands | 3 Months Ended |
--- | --- | ---
Mar. 31, 2022 | Mar. 31, 2021 | Dec. 31, 2021
Impaired Financing Receivable, Recorded Investment [Abstract] |  |  |
Impaired loans with a valuation allowance, Outstanding Balance | $ 6,153 |  | $ 6,411
Impaired loans without a valuation allowance, Outstanding Balance | 17,310 |  | 20,499
Impaired loans, Outstanding Balance | 23,463 |  | 26,910
Impaired Financing Receivable, Unpaid Principal Balance [Abstract] |  |  |
Impaired loans with a valuation allowance, Unpaid Principal Balance | 6,425 |  | 6,683
Impaired loans without a valuation allowance, Unpaid Principal Balance | 17,626 |  | 20,815
Impaired loans, Unpaid Principal Balance | 24,051 |  | 27,498
Impaired loans, Valuation Allowance | 573 |  | 578
Impaired Financing Receivable, Average Recorded Investment [Abstract] |  |  |
Impaired loans with a valuation allowance, Average Outstanding Balance | 6,280 | $ 8,894 |
Impaired loans without a valuation allowance, Average Outstanding Balance | 18,907 | 22,022 |
Impaired loans, Average Outstanding Balance | 25,187 | 30,916 |
Impaired Financing Receivable, Interest Income, Accrual Method [Abstract] |  |  |
Impaired loans with a valuation allowance, Interest Income Recognized | 68 | 82 |
Impaired loans without a valuation allowance, Interest Income Recognized | 265 | 334 |
Impaired loans, Interest Income Recognized | 333 | 416 |
Total commercial [Member] |  |  |
Impaired Financing Receivable, Recorded Investment [Abstract] |  |  |
Impaired loans, Outstanding Balance | 9,072 |  | 9,267
Impaired Financing Receivable, Unpaid Principal Balance [Abstract] |  |  |
Impaired loans, Unpaid Principal Balance | 9,388 |  | 9,584
Impaired loans, Valuation Allowance | 9 |  | 13
Impaired Financing Receivable, Average Recorded Investment [Abstract] |  |  |
Impaired loans, Average Outstanding Balance | 9,168 | 12,059 |
Impaired Financing Receivable, Interest Income, Accrual Method [Abstract] |  |  |
Impaired loans, Interest Income Recognized | 129 | 169 |
Commercial real estate [Member] |  |  |
Impaired Financing Receivable, Recorded Investment [Abstract] |  |  |
Impaired loans with a valuation allowance, Outstanding Balance | 192 |  | 192
Impaired loans without a valuation allowance, Outstanding Balance | 5,740 |  | 5,829
Impaired Financing Receivable, Unpaid Principal Balance [Abstract] |  |  |
Impaired loans with a valuation allowance, Unpaid Principal Balance | 192 |  | 193
Impaired loans without a valuation allowance, Unpaid Principal Balance | 6,056 |  | 6,145
Impaired loans, Valuation Allowance | 8 |  | 9
Impaired Financing Receivable, Average Recorded Investment [Abstract] |  |  |
Impaired loans with a valuation allowance, Average Outstanding Balance | 189 | 2,424 |
Impaired loans without a valuation allowance, Average Outstanding Balance | 5,785 | 4,907 |
Impaired Financing Receivable, Interest Income, Accrual Method [Abstract] |  |  |
Impaired loans with a valuation allowance, Interest Income Recognized | 3 | 28 |
Impaired loans without a valuation allowance, Interest Income Recognized | 85 | 101 |
Commercial other [Member] |  |  |
Impaired Financing Receivable, Recorded Investment [Abstract] |  |  |
Impaired loans with a valuation allowance, Outstanding Balance | 2,671 |  | 2,802
Impaired loans without a valuation allowance, Outstanding Balance | 469 |  | 444
Impaired Financing Receivable, Unpaid Principal Balance [Abstract] |  |  |
Impaired loans with a valuation allowance, Unpaid Principal Balance | 2,671 |  | 2,802
Impaired loans without a valuation allowance, Unpaid Principal Balance | 469 |  | 444
Impaired loans, Valuation Allowance | 1 |  | 4
Impaired Financing Receivable, Average Recorded Investment [Abstract] |  |  |
Impaired loans with a valuation allowance, Average Outstanding Balance | 2,737 | 54 |
Impaired loans without a valuation allowance, Average Outstanding Balance | 457 | 4,674 |
Impaired Financing Receivable, Interest Income, Accrual Method [Abstract] |  |  |
Impaired loans with a valuation allowance, Interest Income Recognized | 30 | 0 |
Impaired loans without a valuation allowance, Interest Income Recognized | 11 | 40 |
Total agricultural [Member] |  |  |
Impaired Financing Receivable, Recorded Investment [Abstract] |  |  |
Impaired loans, Outstanding Balance | 11,101 |  | 14,189
Impaired Financing Receivable, Unpaid Principal Balance [Abstract] |  |  |
Impaired loans, Unpaid Principal Balance | 11,101 |  | 14,189
Impaired loans, Valuation Allowance | 0 |  | 0
Impaired Financing Receivable, Average Recorded Investment [Abstract] |  |  |
Impaired loans, Average Outstanding Balance | 12,646 | 14,629 |
Impaired Financing Receivable, Interest Income, Accrual Method [Abstract] |  |  |
Impaired loans, Interest Income Recognized | 169 | 204 |
Agricultural real estate [Member] |  |  |
Impaired Financing Receivable, Recorded Investment [Abstract] |  |  |
Impaired loans without a valuation allowance, Outstanding Balance | 7,967 |  | 9,538
Impaired Financing Receivable, Unpaid Principal Balance [Abstract] |  |  |
Impaired loans without a valuation allowance, Unpaid Principal Balance | 7,967 |  | 9,538
Impaired Financing Receivable, Average Recorded Investment [Abstract] |  |  |
Impaired loans with a valuation allowance, Average Outstanding Balance | 0 | 1,510 |
Impaired loans without a valuation allowance, Average Outstanding Balance | 8,753 | 9,418 |
Impaired Financing Receivable, Interest Income, Accrual Method [Abstract] |  |  |
Impaired loans with a valuation allowance, Interest Income Recognized | 0 | 11 |
Impaired loans without a valuation allowance, Interest Income Recognized | 124 | 132 |
Agricultural other [Member] |  |  |
Impaired Financing Receivable, Recorded Investment [Abstract] |  |  |
Impaired loans without a valuation allowance, Outstanding Balance | 3,134 |  | 4,651
Impaired Financing Receivable, Unpaid Principal Balance [Abstract] |  |  |
Impaired loans without a valuation allowance, Unpaid Principal Balance | 3,134 |  | 4,651
Impaired Financing Receivable, Average Recorded Investment [Abstract] |  |  |
Impaired loans with a valuation allowance, Average Outstanding Balance | 0 | 678 |
Impaired loans without a valuation allowance, Average Outstanding Balance | 3,893 | 3,023 |
Impaired Financing Receivable, Interest Income, Accrual Method [Abstract] |  |  |
Impaired loans with a valuation allowance, Interest Income Recognized | 0 | 0 |
Impaired loans without a valuation allowance, Interest Income Recognized | 45 | 61 |
Total residential real estate [Member] |  |  |
Impaired Financing Receivable, Recorded Investment [Abstract] |  |  |
Impaired loans, Outstanding Balance | 3,290 |  | 3,454
Impaired Financing Receivable, Unpaid Principal Balance [Abstract] |  |  |
Impaired loans, Unpaid Principal Balance | 3,562 |  | 3,725
Impaired loans, Valuation Allowance | 564 |  | 565
Impaired Financing Receivable, Average Recorded Investment [Abstract] |  |  |
Impaired loans, Average Outstanding Balance | 3,373 | 4,228 |
Impaired Financing Receivable, Interest Income, Accrual Method [Abstract] |  |  |
Impaired loans, Interest Income Recognized | 35 | 43 |
Residential real estate senior liens [Member] |  |  |
Impaired Financing Receivable, Recorded Investment [Abstract] |  |  |
Impaired loans with a valuation allowance, Outstanding Balance | 3,290 |  | 3,417
Impaired Financing Receivable, Unpaid Principal Balance [Abstract] |  |  |
Impaired loans with a valuation allowance, Unpaid Principal Balance | 3,562 |  | 3,688
Impaired loans, Valuation Allowance | 564 |  | 565
Impaired Financing Receivable, Average Recorded Investment [Abstract] |  |  |
Impaired loans with a valuation allowance, Average Outstanding Balance | 3,354 | 4,228 |
Impaired Financing Receivable, Interest Income, Accrual Method [Abstract] |  |  |
Impaired loans with a valuation allowance, Interest Income Recognized | 35 | 43 |
Residential real estate home equity lines of credit [Member] |  |  |
Impaired Financing Receivable, Recorded Investment [Abstract] |  |  |
Impaired loans without a valuation allowance, Outstanding Balance | 0 |  | 37
Impaired Financing Receivable, Unpaid Principal Balance [Abstract] |  |  |
Impaired loans without a valuation allowance, Unpaid Principal Balance | 0 |  | $ 37
Impaired Financing Receivable, Average Recorded Investment [Abstract] |  |  |
Impaired loans without a valuation allowance, Average Outstanding Balance | 19 | 0 |
Impaired Financing Receivable, Interest Income, Accrual Method [Abstract] |  |  |
Impaired loans without a valuation allowance, Interest Income Recognized | $ 0 | $ 0 |

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