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Loans and ALLL (Summary of information pertaining to impaired loans) (Details) - USD ($) $ in Thousands | 3 Months Ended |
--- | --- | ---
Mar. 31, 2021 | Mar. 31, 2020 | Dec. 31, 2020
Impaired Financing Receivable, Recorded Investment [Abstract] |  |  |
Impaired loans with a valuation allowance, Outstanding Balance | $ 7,966 |  | $ 9,823
Impaired loans without a valuation allowance, Outstanding Balance | 25,929 |  | 18,113
Impaired loans, Outstanding Balance | 33,895 |  | 27,936
Impaired Financing Receivable, Unpaid Principal Balance [Abstract] |  |  |
Impaired loans with a valuation allowance, Unpaid Principal Balance | 8,274 |  | 10,407
Impaired loans without a valuation allowance, Unpaid Principal Balance | 26,245 |  | 18,237
Impaired loans, Unpaid Principal Balance | 34,519 |  | 28,644
Impaired loans, Valuation Allowance | 1,380 |  | 911
Impaired Financing Receivable, Average Recorded Investment [Abstract] |  |  |
Impaired loans with a valuation allowance, Average Outstanding Balance | 8,894 | $ 9,857 |
Impaired loans without a valuation allowance, Average Outstanding Balance | 22,022 | 18,058 |
Impaired loans, Average Outstanding Balance | 30,916 | 27,915 |
Impaired Financing Receivable, Interest Income, Accrual Method [Abstract] |  |  |
Impaired loans with a valuation allowance, Interest Income Recognized | 82 | 132 |
Impaired loans without a valuation allowance, Interest Income Recognized | 334 | 146 |
Impaired loans, Interest Income Recognized | 416 | 278 |
Total commercial [Member] |  |  |
Impaired Financing Receivable, Recorded Investment [Abstract] |  |  |
Impaired loans, Outstanding Balance | 14,300 |  | 9,821
Impaired Financing Receivable, Unpaid Principal Balance [Abstract] |  |  |
Impaired loans, Unpaid Principal Balance | 14,616 |  | 10,137
Impaired loans, Valuation Allowance | 587 |  | 84
Impaired Financing Receivable, Average Recorded Investment [Abstract] |  |  |
Impaired loans, Average Outstanding Balance | 12,059 | 8,233 |
Impaired Financing Receivable, Interest Income, Accrual Method [Abstract] |  |  |
Impaired loans, Interest Income Recognized | 169 | 105 |
Commercial real estate [Member] |  |  |
Impaired Financing Receivable, Recorded Investment [Abstract] |  |  |
Impaired loans with a valuation allowance, Outstanding Balance | 2,805 |  | 2,048
Impaired loans without a valuation allowance, Outstanding Balance | 6,807 |  | 3,006
Impaired Financing Receivable, Unpaid Principal Balance [Abstract] |  |  |
Impaired loans with a valuation allowance, Unpaid Principal Balance | 2,805 |  | 2,290
Impaired loans without a valuation allowance, Unpaid Principal Balance | 7,123 |  | 3,080
Impaired loans, Valuation Allowance | 587 |  | 79
Impaired Financing Receivable, Average Recorded Investment [Abstract] |  |  |
Impaired loans with a valuation allowance, Average Outstanding Balance | 2,424 | 821 |
Impaired loans without a valuation allowance, Average Outstanding Balance | 4,907 | 4,562 |
Impaired Financing Receivable, Interest Income, Accrual Method [Abstract] |  |  |
Impaired loans with a valuation allowance, Interest Income Recognized | 28 | 25 |
Impaired loans without a valuation allowance, Interest Income Recognized | 101 | 59 |
Commercial other [Member] |  |  |
Impaired Financing Receivable, Recorded Investment [Abstract] |  |  |
Impaired loans with a valuation allowance, Outstanding Balance | 0 |  | 107
Impaired loans without a valuation allowance, Outstanding Balance | 4,688 |  | 4,660
Impaired Financing Receivable, Unpaid Principal Balance [Abstract] |  |  |
Impaired loans with a valuation allowance, Unpaid Principal Balance | 0 |  | 107
Impaired loans without a valuation allowance, Unpaid Principal Balance | 4,688 |  | 4,660
Impaired loans, Valuation Allowance | 0 |  | 5
Impaired Financing Receivable, Average Recorded Investment [Abstract] |  |  |
Impaired loans with a valuation allowance, Average Outstanding Balance | 54 | 460 |
Impaired loans without a valuation allowance, Average Outstanding Balance | 4,674 | 2,390 |
Impaired Financing Receivable, Interest Income, Accrual Method [Abstract] |  |  |
Impaired loans with a valuation allowance, Interest Income Recognized | 0 | 6 |
Impaired loans without a valuation allowance, Interest Income Recognized | 40 | 15 |
Total agricultural [Member] |  |  |
Impaired Financing Receivable, Recorded Investment [Abstract] |  |  |
Impaired loans, Outstanding Balance | 15,459 |  | 13,796
Impaired Financing Receivable, Unpaid Principal Balance [Abstract] |  |  |
Impaired loans, Unpaid Principal Balance | 15,509 |  | 13,846
Impaired loans, Valuation Allowance | 25 |  | 56
Impaired Financing Receivable, Average Recorded Investment [Abstract] |  |  |
Impaired loans, Average Outstanding Balance | 14,629 | 14,250 |
Impaired Financing Receivable, Interest Income, Accrual Method [Abstract] |  |  |
Impaired loans, Interest Income Recognized | 204 | 112 |
Agricultural real estate [Member] |  |  |
Impaired Financing Receivable, Recorded Investment [Abstract] |  |  |
Impaired loans with a valuation allowance, Outstanding Balance | 1,025 |  | 1,994
Impaired loans without a valuation allowance, Outstanding Balance | 10,155 |  | 8,681
Impaired Financing Receivable, Unpaid Principal Balance [Abstract] |  |  |
Impaired loans with a valuation allowance, Unpaid Principal Balance | 1,075 |  | 1,994
Impaired loans without a valuation allowance, Unpaid Principal Balance | 10,155 |  | 8,731
Impaired loans, Valuation Allowance | 25 |  | 54
Impaired Financing Receivable, Average Recorded Investment [Abstract] |  |  |
Impaired loans with a valuation allowance, Average Outstanding Balance | 1,510 | 1,878 |
Impaired loans without a valuation allowance, Average Outstanding Balance | 9,418 | 7,782 |
Impaired Financing Receivable, Interest Income, Accrual Method [Abstract] |  |  |
Impaired loans with a valuation allowance, Interest Income Recognized | 11 | 24 |
Impaired loans without a valuation allowance, Interest Income Recognized | 132 | 59 |
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 | 4,279 |  | 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 | 4,279 |  | 1,766
Impaired loans, Valuation Allowance | 0 |  | 2
Impaired Financing Receivable, Average Recorded Investment [Abstract] |  |  |
Impaired loans with a valuation allowance, Average Outstanding Balance | 678 | 1,355 |
Impaired loans without a valuation allowance, Average Outstanding Balance | 3,023 | 3,235 |
Impaired Financing Receivable, Interest Income, Accrual Method [Abstract] |  |  |
Impaired loans with a valuation allowance, Interest Income Recognized | 0 | 22 |
Impaired loans without a valuation allowance, Interest Income Recognized | 61 | 7 |
Total residential real estate [Member] |  |  |
Impaired Financing Receivable, Recorded Investment [Abstract] |  |  |
Impaired loans, Outstanding Balance | 4,136 |  | 4,319
Impaired Financing Receivable, Unpaid Principal Balance [Abstract] |  |  |
Impaired loans, Unpaid Principal Balance | 4,394 |  | 4,661
Impaired loans, Valuation Allowance | 768 |  | 771
Impaired Financing Receivable, Average Recorded Investment [Abstract] |  |  |
Impaired loans, Average Outstanding Balance | 4,228 | 5,430 |
Impaired Financing Receivable, Interest Income, Accrual Method [Abstract] |  |  |
Impaired loans, Interest Income Recognized | 43 | 61 |
Residential real estate senior liens [Member] |  |  |
Impaired Financing Receivable, Recorded Investment [Abstract] |  |  |
Impaired loans with a valuation allowance, Outstanding Balance | 4,136 |  | 4,319
Impaired Financing Receivable, Unpaid Principal Balance [Abstract] |  |  |
Impaired loans with a valuation allowance, Unpaid Principal Balance | 4,394 |  | 4,661
Impaired loans, Valuation Allowance | 768 |  | $ 771
Impaired Financing Receivable, Average Recorded Investment [Abstract] |  |  |
Impaired loans with a valuation allowance, Average Outstanding Balance | 4,228 | 5,343 |
Impaired Financing Receivable, Interest Income, Accrual Method [Abstract] |  |  |
Impaired loans with a valuation allowance, Interest Income Recognized | 43 | 55 |
Residential real estate home equity lines of credit [Member] |  |  |
Impaired Financing Receivable, Average Recorded Investment [Abstract] |  |  |
Impaired loans without a valuation allowance, Average Outstanding Balance | 0 | 87 |
Impaired Financing Receivable, Interest Income, Accrual Method [Abstract] |  |  |
Impaired loans without a valuation allowance, Interest Income Recognized | 0 | 6 |
Total Consumer [Member] |  |  |
Impaired Financing Receivable, Average Recorded Investment [Abstract] |  |  |
Impaired loans, Average Outstanding Balance | 0 | 2 |
Impaired Financing Receivable, Interest Income, Accrual Method [Abstract] |  |  |
Impaired loans, Interest Income Recognized | 0 | 0 |
Consumer secured [Member] |  |  |
Impaired Financing Receivable, Average Recorded Investment [Abstract] |  |  |
Impaired loans without a valuation allowance, Average Outstanding Balance | 0 | 2 |
Impaired Financing Receivable, Interest Income, Accrual Method [Abstract] |  |  |
Impaired loans without a valuation allowance, Interest Income Recognized | $ 0 | $ 0 |

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