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Loans and ALLL (Summary of information pertaining to impaired loans) (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2022 | Sep. 30, 2021 | Sep. 30, 2022 | Sep. 30, 2021 | Dec. 31, 2021
Impaired Financing Receivable, Recorded Investment [Abstract] |  |  |  |  |
Impaired loans with a valuation allowance, Outstanding Balance | $ 3,045 |  | $ 3,045 |  | $ 6,411
Impaired loans without a valuation allowance, Outstanding Balance | 16,706 |  | 16,706 |  | 20,499
Impaired loans, Outstanding Balance | 19,751 |  | 19,751 |  | 26,910
Impaired Financing Receivable, Unpaid Principal Balance [Abstract] |  |  |  |  |
Impaired loans with a valuation allowance, Unpaid Principal Balance | 3,289 |  | 3,289 |  | 6,683
Impaired loans without a valuation allowance, Unpaid Principal Balance | 17,022 |  | 17,022 |  | 20,815
Impaired loans, Unpaid Principal Balance | 20,311 |  | 20,311 |  | 27,498
Impaired loans, Valuation Allowance | 474 |  | 474 |  | 578
Impaired Financing Receivable, Average Recorded Investment [Abstract] |  |  |  |  |
Impaired loans with a valuation allowance, Average Outstanding Balance | 4,528 | $ 8,146 | 5,630 | $ 8,601 |
Impaired loans without a valuation allowance, Average Outstanding Balance | 16,840 | 21,957 | 17,629 | 22,478 |
Impaired loans, Average Outstanding Balance | 21,368 | 30,103 | 23,259 | 31,079 |
Impaired Financing Receivable, Interest Income, Accrual Method [Abstract] |  |  |  |  |
Impaired loans with a valuation allowance, Interest Income Recognized | 34 | 75 | 168 | 263 |
Impaired loans without a valuation allowance, Interest Income Recognized | 244 | 301 | 729 | 926 |
Impaired loans, Interest Income Recognized | 278 | 376 | 897 | 1,189 |
Total commercial [Member] |  |  |  |  |
Impaired Financing Receivable, Recorded Investment [Abstract] |  |  |  |  |
Impaired loans, Outstanding Balance | 5,703 |  | 5,703 |  | 9,267
Impaired Financing Receivable, Unpaid Principal Balance [Abstract] |  |  |  |  |
Impaired loans, Unpaid Principal Balance | 6,019 |  | 6,019 |  | 9,584
Impaired loans, Valuation Allowance | 14 |  | 14 |  | 13
Impaired Financing Receivable, Average Recorded Investment [Abstract] |  |  |  |  |
Impaired loans, Average Outstanding Balance | 7,168 | 11,785 | 8,396 | 12,333 |
Impaired Financing Receivable, Interest Income, Accrual Method [Abstract] |  |  |  |  |
Impaired loans, Interest Income Recognized | 88 | 168 | 345 | 511 |
Commercial real estate [Member] |  |  |  |  |
Impaired Financing Receivable, Recorded Investment [Abstract] |  |  |  |  |
Impaired loans with a valuation allowance, Outstanding Balance | 185 |  | 185 |  | 192
Impaired loans without a valuation allowance, Outstanding Balance | 5,319 |  | 5,319 |  | 5,829
Impaired Financing Receivable, Unpaid Principal Balance [Abstract] |  |  |  |  |
Impaired loans with a valuation allowance, Unpaid Principal Balance | 185 |  | 185 |  | 193
Impaired loans without a valuation allowance, Unpaid Principal Balance | 5,635 |  | 5,635 |  | 6,145
Impaired loans, Valuation Allowance | 14 |  | 14 |  | 9
Impaired Financing Receivable, Average Recorded Investment [Abstract] |  |  |  |  |
Impaired loans with a valuation allowance, Average Outstanding Balance | 188 | 1,377 | 190 | 2,161 |
Impaired loans without a valuation allowance, Average Outstanding Balance | 5,359 | 7,013 | 5,571 | 6,109 |
Impaired Financing Receivable, Interest Income, Accrual Method [Abstract] |  |  |  |  |
Impaired loans with a valuation allowance, Interest Income Recognized | 3 | 3 | 9 | 66 |
Impaired loans without a valuation allowance, Interest Income Recognized | 82 | 121 | 256 | 315 |
Commercial other [Member] |  |  |  |  |
Impaired Financing Receivable, Recorded Investment [Abstract] |  |  |  |  |
Impaired loans with a valuation allowance, Outstanding Balance | 0 |  | 0 |  | 2,802
Impaired loans without a valuation allowance, Outstanding Balance | 199 |  | 199 |  | 444
Impaired Financing Receivable, Unpaid Principal Balance [Abstract] |  |  |  |  |
Impaired loans with a valuation allowance, Unpaid Principal Balance | 0 |  | 0 |  | 2,802
Impaired loans without a valuation allowance, Unpaid Principal Balance | 199 |  | 199 |  | 444
Impaired loans, Valuation Allowance | 0 |  | 0 |  | 4
Impaired Financing Receivable, Average Recorded Investment [Abstract] |  |  |  |  |
Impaired loans with a valuation allowance, Average Outstanding Balance | 1,413 | 3,090 | 2,299 | 1,569 |
Impaired loans without a valuation allowance, Average Outstanding Balance | 208 | 305 | 336 | 2,494 |
Impaired Financing Receivable, Interest Income, Accrual Method [Abstract] |  |  |  |  |
Impaired loans with a valuation allowance, Interest Income Recognized | 0 | 35 | 62 | 71 |
Impaired loans without a valuation allowance, Interest Income Recognized | 3 | 9 | 18 | 59 |
Total agricultural [Member] |  |  |  |  |
Impaired Financing Receivable, Recorded Investment [Abstract] |  |  |  |  |
Impaired loans, Outstanding Balance | 11,188 |  | 11,188 |  | 14,189
Impaired Financing Receivable, Unpaid Principal Balance [Abstract] |  |  |  |  |
Impaired loans, Unpaid Principal Balance | 11,188 |  | 11,188 |  | 14,189
Impaired loans, Valuation Allowance | 0 |  | 0 |  | 0
Impaired Financing Receivable, Average Recorded Investment [Abstract] |  |  |  |  |
Impaired loans, Average Outstanding Balance | 11,273 | 14,733 | 11,716 | 14,838 |
Impaired Financing Receivable, Interest Income, Accrual Method [Abstract] |  |  |  |  |
Impaired loans, Interest Income Recognized | 159 | 171 | 455 | 563 |
Agricultural real estate [Member] |  |  |  |  |
Impaired Financing Receivable, Recorded Investment [Abstract] |  |  |  |  |
Impaired loans without a valuation allowance, Outstanding Balance | 8,611 |  | 8,611 |  | 9,538
Impaired Financing Receivable, Unpaid Principal Balance [Abstract] |  |  |  |  |
Impaired loans without a valuation allowance, Unpaid Principal Balance | 8,611 |  | 8,611 |  | 9,538
Impaired Financing Receivable, Average Recorded Investment [Abstract] |  |  |  |  |
Impaired loans with a valuation allowance, Average Outstanding Balance | 0 | 94 | 0 | 737 |
Impaired loans without a valuation allowance, Average Outstanding Balance | 8,638 | 9,845 | 8,569 | 9,760 |
Impaired Financing Receivable, Interest Income, Accrual Method [Abstract] |  |  |  |  |
Impaired loans with a valuation allowance, Interest Income Recognized | 0 | 0 | 0 | 11 |
Impaired loans without a valuation allowance, Interest Income Recognized | 116 | 113 | 341 | 378 |
Agricultural other [Member] |  |  |  |  |
Impaired Financing Receivable, Recorded Investment [Abstract] |  |  |  |  |
Impaired loans without a valuation allowance, Outstanding Balance | 2,577 |  | 2,577 |  | 4,651
Impaired Financing Receivable, Unpaid Principal Balance [Abstract] |  |  |  |  |
Impaired loans without a valuation allowance, Unpaid Principal Balance | 2,577 |  | 2,577 |  | 4,651
Impaired Financing Receivable, Average Recorded Investment [Abstract] |  |  |  |  |
Impaired loans with a valuation allowance, Average Outstanding Balance |  |  | 0 | 226 |
Impaired loans without a valuation allowance, Average Outstanding Balance | 2,635 | 4,794 | 3,147 | 4,115 |
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 | 43 | 58 | 114 | 174 |
Total residential real estate [Member] |  |  |  |  |
Impaired Financing Receivable, Recorded Investment [Abstract] |  |  |  |  |
Impaired loans, Outstanding Balance | 2,860 |  | 2,860 |  | 3,454
Impaired Financing Receivable, Unpaid Principal Balance [Abstract] |  |  |  |  |
Impaired loans, Unpaid Principal Balance | 3,104 |  | 3,104 |  | 3,725
Impaired loans, Valuation Allowance | 460 |  | 460 |  | 565
Impaired Financing Receivable, Average Recorded Investment [Abstract] |  |  |  |  |
Impaired loans, Average Outstanding Balance | 2,927 | 3,585 | 3,147 | 3,908 |
Impaired Financing Receivable, Interest Income, Accrual Method [Abstract] |  |  |  |  |
Impaired loans, Interest Income Recognized | 31 | 37 | 97 | 115 |
Residential real estate senior liens [Member] |  |  |  |  |
Impaired Financing Receivable, Recorded Investment [Abstract] |  |  |  |  |
Impaired loans with a valuation allowance, Outstanding Balance | 2,860 |  | 2,860 |  | 3,417
Impaired Financing Receivable, Unpaid Principal Balance [Abstract] |  |  |  |  |
Impaired loans with a valuation allowance, Unpaid Principal Balance | 3,104 |  | 3,104 |  | 3,688
Impaired loans, Valuation Allowance | 460 |  | 460 |  | 565
Impaired Financing Receivable, Average Recorded Investment [Abstract] |  |  |  |  |
Impaired loans with a valuation allowance, Average Outstanding Balance | 2,927 | 3,585 | 3,141 | 3,908 |
Impaired Financing Receivable, Interest Income, Accrual Method [Abstract] |  |  |  |  |
Impaired loans with a valuation allowance, Interest Income Recognized | 31 | $ 37 | 97 | 115 |
Residential real estate home equity lines of credit [Member] |  |  |  |  |
Impaired Financing Receivable, Recorded Investment [Abstract] |  |  |  |  |
Impaired loans without a valuation allowance, Outstanding Balance | 0 |  | 0 |  | 37
Impaired Financing Receivable, Unpaid Principal Balance [Abstract] |  |  |  |  |
Impaired loans without a valuation allowance, Unpaid Principal Balance | $ 0 |  | 0 |  | $ 37
Impaired Financing Receivable, Average Recorded Investment [Abstract] |  |  |  |  |
Impaired loans without a valuation allowance, Average Outstanding Balance |  |  | 6 | 0 |
Impaired Financing Receivable, Interest Income, Accrual Method [Abstract] |  |  |  |  |
Impaired loans without a valuation allowance, Interest Income Recognized |  |  | $ 0 | $ 0 |

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