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Loans and ALLL (Summary of information pertaining to impaired loans) (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2021 | Dec. 31, 2020
Impaired Financing Receivable, Recorded Investment [Abstract] |  |
Impaired loans with a valuation allowance, Outstanding Balance | $ 6,411 | $ 9,823
Impaired loans without a valuation allowance, Outstanding Balance | 20,499 | 18,113
Impaired loans, Outstanding Balance | 26,910 | 27,936
Impaired Financing Receivable, Unpaid Principal Balance [Abstract] |  |
Impaired loans with a valuation allowance, Unpaid Principal Balance | 6,683 | 10,407
Impaired loans without a valuation allowance, Unpaid Principal Balance | 20,815 | 18,237
Impaired loans, Unpaid Principal Balance | 27,498 | 28,644
Impaired loans, Valuation Allowance | 578 | 911
Impaired Financing Receivable, Average Recorded Investment [Abstract] |  |
Impaired loans with a valuation allowance, Average Outstanding Balance | 8,093 | 10,138
Impaired loans without a valuation allowance, Average Outstanding Balance | 22,289 | 17,536
Impaired loans, Average Outstanding Balance | 30,382 | 27,674
Impaired Financing Receivable, Interest Income, Accrual Method [Abstract] |  |
Impaired loans with a valuation allowance, Interest Income Recognized | 334 | 519
Impaired loans without a valuation allowance, Interest Income Recognized | 1,400 | 772
Impaired loans, Interest Income Recognized | 1,734 | 1,291
Total commercial [Member] |  |
Impaired Financing Receivable, Recorded Investment [Abstract] |  |
Impaired loans, Outstanding Balance | 9,267 | 9,821
Impaired Financing Receivable, Unpaid Principal Balance [Abstract] |  |
Impaired loans, Unpaid Principal Balance | 9,584 | 10,137
Impaired loans, Valuation Allowance | 13 | 84
Impaired Financing Receivable, Average Recorded Investment [Abstract] |  |
Impaired loans, Average Outstanding Balance | 11,853 | 9,257
Impaired Financing Receivable, Interest Income, Accrual Method [Abstract] |  |
Impaired loans, Interest Income Recognized | 638 | 501
Commercial real estate [Member] |  |
Impaired Financing Receivable, Recorded Investment [Abstract] |  |
Impaired loans with a valuation allowance, Outstanding Balance | 192 | 2,048
Impaired loans without a valuation allowance, Outstanding Balance | 5,829 | 3,006
Impaired Financing Receivable, Unpaid Principal Balance [Abstract] |  |
Impaired loans with a valuation allowance, Unpaid Principal Balance | 193 | 2,290
Impaired loans without a valuation allowance, Unpaid Principal Balance | 6,145 | 3,080
Impaired loans, Valuation Allowance | 9 | 79
Impaired Financing Receivable, Average Recorded Investment [Abstract] |  |
Impaired loans with a valuation allowance, Average Outstanding Balance | 1,668 | 1,384
Impaired loans without a valuation allowance, Average Outstanding Balance | 6,313 | 3,679
Impaired Financing Receivable, Interest Income, Accrual Method [Abstract] |  |
Impaired loans with a valuation allowance, Interest Income Recognized | 69 | 121
Impaired loans without a valuation allowance, Interest Income Recognized | 398 | 210
Commercial other [Member] |  |
Impaired Financing Receivable, Recorded Investment [Abstract] |  |
Impaired loans with a valuation allowance, Outstanding Balance | 2,802 | 107
Impaired loans without a valuation allowance, Outstanding Balance | 444 | 4,660
Impaired Financing Receivable, Unpaid Principal Balance [Abstract] |  |
Impaired loans with a valuation allowance, Unpaid Principal Balance | 2,802 | 107
Impaired loans without a valuation allowance, Unpaid Principal Balance | 444 | 4,660
Impaired loans, Valuation Allowance | 4 | 5
Impaired Financing Receivable, Average Recorded Investment [Abstract] |  |
Impaired loans with a valuation allowance, Average Outstanding Balance | 1,909 | 464
Impaired loans without a valuation allowance, Average Outstanding Balance | 1,963 | 3,730
Impaired Financing Receivable, Interest Income, Accrual Method [Abstract] |  |
Impaired loans with a valuation allowance, Interest Income Recognized | 103 | 20
Impaired loans without a valuation allowance, Interest Income Recognized | 68 | 150
Total agricultural [Member] |  |
Impaired Financing Receivable, Recorded Investment [Abstract] |  |
Impaired loans, Outstanding Balance | 14,189 | 13,796
Impaired Financing Receivable, Unpaid Principal Balance [Abstract] |  |
Impaired loans, Unpaid Principal Balance | 14,189 | 13,846
Impaired loans, Valuation Allowance | 0 | 56
Impaired Financing Receivable, Average Recorded Investment [Abstract] |  |
Impaired loans, Average Outstanding Balance | 14,730 | 13,519
Impaired Financing Receivable, Interest Income, Accrual Method [Abstract] |  |
Impaired loans, Interest Income Recognized | 945 | 588
Agricultural real estate [Member] |  |
Impaired Financing Receivable, Recorded Investment [Abstract] |  |
Impaired loans with a valuation allowance, Outstanding Balance | 0 | 1,994
Impaired loans without a valuation allowance, Outstanding Balance | 9,538 | 8,681
Impaired Financing Receivable, Unpaid Principal Balance [Abstract] |  |
Impaired loans with a valuation allowance, Unpaid Principal Balance | 0 | 1,994
Impaired loans without a valuation allowance, Unpaid Principal Balance | 9,538 | 8,731
Impaired loans, Valuation Allowance | 0 | 54
Impaired Financing Receivable, Average Recorded Investment [Abstract] |  |
Impaired loans with a valuation allowance, Average Outstanding Balance | 553 | 2,099
Impaired loans without a valuation allowance, Average Outstanding Balance | 9,739 | 7,704
Impaired Financing Receivable, Interest Income, Accrual Method [Abstract] |  |
Impaired loans with a valuation allowance, Interest Income Recognized | 11 | 103
Impaired loans without a valuation allowance, Interest Income Recognized | 699 | 302
Agricultural other [Member] |  |
Impaired Financing Receivable, Recorded Investment [Abstract] |  |
Impaired loans with a valuation allowance, Outstanding Balance | 0 | 1,355
Impaired loans without a valuation allowance, Outstanding Balance | 4,651 | 1,766
Impaired Financing Receivable, Unpaid Principal Balance [Abstract] |  |
Impaired loans with a valuation allowance, Unpaid Principal Balance | 0 | 1,355
Impaired loans without a valuation allowance, Unpaid Principal Balance | 4,651 | 1,766
Impaired loans, Valuation Allowance | 0 | 2
Impaired Financing Receivable, Average Recorded Investment [Abstract] |  |
Impaired loans with a valuation allowance, Average Outstanding Balance | 169 | 1,355
Impaired loans without a valuation allowance, Average Outstanding Balance | 4,269 | 2,361
Impaired Financing Receivable, Interest Income, Accrual Method [Abstract] |  |
Impaired loans with a valuation allowance, Interest Income Recognized | 0 | 78
Impaired loans without a valuation allowance, Interest Income Recognized | 235 | 105
Total residential real estate [Member] |  |
Impaired Financing Receivable, Recorded Investment [Abstract] |  |
Impaired loans, Outstanding Balance | 3,454 | 4,319
Impaired Financing Receivable, Unpaid Principal Balance [Abstract] |  |
Impaired loans, Unpaid Principal Balance | 3,725 | 4,661
Impaired loans, Valuation Allowance | 565 | 771
Impaired Financing Receivable, Average Recorded Investment [Abstract] |  |
Impaired loans, Average Outstanding Balance | 3,799 | 4,897
Impaired Financing Receivable, Interest Income, Accrual Method [Abstract] |  |
Impaired loans, Interest Income Recognized | 151 | 202
Residential real estate senior liens [Member] |  |
Impaired Financing Receivable, Recorded Investment [Abstract] |  |
Impaired loans with a valuation allowance, Outstanding Balance | 3,417 | 4,319
Impaired Financing Receivable, Unpaid Principal Balance [Abstract] |  |
Impaired loans with a valuation allowance, Unpaid Principal Balance | 3,688 | 4,661
Impaired loans, Valuation Allowance | 565 | 771
Impaired Financing Receivable, Average Recorded Investment [Abstract] |  |
Impaired loans with a valuation allowance, Average Outstanding Balance | 3,794 | 4,836
Impaired Financing Receivable, Interest Income, Accrual Method [Abstract] |  |
Impaired loans with a valuation allowance, Interest Income Recognized | 151 | 197
Residential real estate home equity lines of credit [Member] |  |
Impaired Financing Receivable, Recorded Investment [Abstract] |  |
Impaired loans without a valuation allowance, Outstanding Balance | 37 | 0
Impaired Financing Receivable, Unpaid Principal Balance [Abstract] |  |
Impaired loans without a valuation allowance, Unpaid Principal Balance | 37 | 0
Impaired Financing Receivable, Average Recorded Investment [Abstract] |  |
Impaired loans without a valuation allowance, Average Outstanding Balance | 5 | 61
Impaired Financing Receivable, Interest Income, Accrual Method [Abstract] |  |
Impaired loans without a valuation allowance, Interest Income Recognized | $ 0 | 5
Total consumer [Member] |  |
Impaired Financing Receivable, Recorded Investment [Abstract] |  |
Impaired loans, Outstanding Balance |  | 0
Impaired Financing Receivable, Unpaid Principal Balance [Abstract] |  |
Impaired loans, Unpaid Principal Balance |  | 0
Impaired loans, Valuation Allowance |  | 0
Impaired Financing Receivable, Average Recorded Investment [Abstract] |  |
Impaired loans, Average Outstanding Balance |  | 1
Impaired Financing Receivable, Interest Income, Accrual Method [Abstract] |  |
Impaired loans, Interest Income Recognized |  | 0
Consumer secured [Member] |  |
Impaired Financing Receivable, Recorded Investment [Abstract] |  |
Impaired loans without a valuation allowance, Outstanding Balance |  | 0
Impaired Financing Receivable, Unpaid Principal Balance [Abstract] |  |
Impaired loans without a valuation allowance, Unpaid Principal Balance |  | 0
Impaired Financing Receivable, Average Recorded Investment [Abstract] |  |
Impaired loans without a valuation allowance, Average Outstanding Balance |  | 1
Impaired Financing Receivable, Interest Income, Accrual Method [Abstract] |  |
Impaired loans without a valuation allowance, Interest Income Recognized |  | $ 0

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