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Loans and ALLL (Summary of information pertaining to impaired loans) (Details) - USD ($) $ in Thousands | 3 Months Ended |
--- | --- | ---
Mar. 31, 2020 | Mar. 31, 2019 | Dec. 31, 2019
Impaired Financing Receivable, Recorded Investment [Abstract] |  |  |
Impaired loans with a valuation allowance, Outstanding Balance | $ 10,931 |  | $ 8,782
Impaired loans without a valuation allowance, Outstanding Balance | 16,704 |  | 19,409
Impaired loans, Outstanding Balance | 27,635 |  | 28,191
Impaired Financing Receivable, Unpaid Principal Balance [Abstract] |  |  |
Impaired loans with a valuation allowance, Unpaid Principal Balance | 11,651 |  | 9,329
Impaired loans without a valuation allowance, Unpaid Principal Balance | 17,143 |  | 20,022
Impaired loans, Unpaid Principal Balance | 28,794 |  | 29,351
Impaired loans, Valuation Allowance | 1,309 |  | 1,114
Impaired Financing Receivable, Average Recorded Investment [Abstract] |  |  |
Impaired loans with a valuation allowance, Average Outstanding Balance | 9,857 | $ 10,549 |
Impaired loans without a valuation allowance, Average Outstanding Balance | 18,058 | 20,019 |
Impaired loans, Average Outstanding Balance | 27,915 | 30,568 |
Impaired Financing Receivable, Interest Income, Accrual Method [Abstract] |  |  |
Impaired loans with a valuation allowance, Interest Income Recognized | 132 | 123 |
Impaired loans without a valuation allowance, Interest Income Recognized | 146 | 157 |
Impaired loans, Interest Income Recognized | 278 | 280 |
Total commercial [Member] |  |  |
Impaired Financing Receivable, Recorded Investment [Abstract] |  |  |
Impaired loans, Outstanding Balance | 8,598 |  | 7,865
Impaired Financing Receivable, Unpaid Principal Balance [Abstract] |  |  |
Impaired loans, Unpaid Principal Balance | 8,979 |  | 8,246
Impaired loans, Valuation Allowance | 179 |  | 15
Impaired Financing Receivable, Average Recorded Investment [Abstract] |  |  |
Impaired loans, Average Outstanding Balance | 8,233 | 9,678 |
Impaired Financing Receivable, Interest Income, Accrual Method [Abstract] |  |  |
Impaired loans, Interest Income Recognized | 105 | 123 |
Commercial real estate [Member] |  |  |
Impaired Financing Receivable, Recorded Investment [Abstract] |  |  |
Impaired loans with a valuation allowance, Outstanding Balance | 1,125 |  | 517
Impaired loans without a valuation allowance, Outstanding Balance | 4,162 |  | 4,961
Impaired Financing Receivable, Unpaid Principal Balance [Abstract] |  |  |
Impaired loans with a valuation allowance, Unpaid Principal Balance | 1,367 |  | 635
Impaired loans without a valuation allowance, Unpaid Principal Balance | 4,301 |  | 5,224
Impaired loans, Valuation Allowance | 66 |  | 15
Impaired Financing Receivable, Average Recorded Investment [Abstract] |  |  |
Impaired loans with a valuation allowance, Average Outstanding Balance | 821 | 3,409 |
Impaired loans without a valuation allowance, Average Outstanding Balance | 4,562 | 3,287 |
Impaired Financing Receivable, Interest Income, Accrual Method [Abstract] |  |  |
Impaired loans with a valuation allowance, Interest Income Recognized | 25 | 49 |
Impaired loans without a valuation allowance, Interest Income Recognized | 59 | 53 |
Commercial other [Member] |  |  |
Impaired Financing Receivable, Recorded Investment [Abstract] |  |  |
Impaired loans with a valuation allowance, Outstanding Balance | 919 |  | 0
Impaired loans without a valuation allowance, Outstanding Balance | 2,392 |  | 2,387
Impaired Financing Receivable, Unpaid Principal Balance [Abstract] |  |  |
Impaired loans with a valuation allowance, Unpaid Principal Balance | 919 |  | 0
Impaired loans without a valuation allowance, Unpaid Principal Balance | 2,392 |  | 2,387
Impaired loans, Valuation Allowance | 113 |  | 0
Impaired Financing Receivable, Average Recorded Investment [Abstract] |  |  |
Impaired loans with a valuation allowance, Average Outstanding Balance | 460 | 12 |
Impaired loans without a valuation allowance, Average Outstanding Balance | 2,390 | 2,970 |
Impaired Financing Receivable, Interest Income, Accrual Method [Abstract] |  |  |
Impaired loans with a valuation allowance, Interest Income Recognized | 6 | 0 |
Impaired loans without a valuation allowance, Interest Income Recognized | 15 | 21 |
Total agricultural [Member] |  |  |
Impaired Financing Receivable, Recorded Investment [Abstract] |  |  |
Impaired loans, Outstanding Balance | 13,660 |  | 14,840
Impaired Financing Receivable, Unpaid Principal Balance [Abstract] |  |  |
Impaired loans, Unpaid Principal Balance | 13,710 |  | 14,890
Impaired loans, Valuation Allowance | 78 |  | 26
Impaired Financing Receivable, Average Recorded Investment [Abstract] |  |  |
Impaired loans, Average Outstanding Balance | 14,250 | 14,144 |
Impaired Financing Receivable, Interest Income, Accrual Method [Abstract] |  |  |
Impaired loans, Interest Income Recognized | 112 | 83 |
Agricultural real estate [Member] |  |  |
Impaired Financing Receivable, Recorded Investment [Abstract] |  |  |
Impaired loans with a valuation allowance, Outstanding Balance | 2,247 |  | 1,509
Impaired loans without a valuation allowance, Outstanding Balance | 7,192 |  | 8,372
Impaired Financing Receivable, Unpaid Principal Balance [Abstract] |  |  |
Impaired loans with a valuation allowance, Unpaid Principal Balance | 2,297 |  | 1,509
Impaired loans without a valuation allowance, Unpaid Principal Balance | 7,192 |  | 8,422
Impaired loans, Valuation Allowance | 70 |  | 12
Impaired Financing Receivable, Average Recorded Investment [Abstract] |  |  |
Impaired loans with a valuation allowance, Average Outstanding Balance | 1,878 | 390 |
Impaired loans without a valuation allowance, Average Outstanding Balance | 7,782 | 7,623 |
Impaired Financing Receivable, Interest Income, Accrual Method [Abstract] |  |  |
Impaired loans with a valuation allowance, Interest Income Recognized | 24 | 6 |
Impaired loans without a valuation allowance, Interest Income Recognized | 59 | 7 |
Agricultural other [Member] |  |  |
Impaired Financing Receivable, Recorded Investment [Abstract] |  |  |
Impaired loans with a valuation allowance, Outstanding Balance | 1,355 |  | 1,355
Impaired loans without a valuation allowance, Outstanding Balance | 2,866 |  | 3,604
Impaired Financing Receivable, Unpaid Principal Balance [Abstract] |  |  |
Impaired loans with a valuation allowance, Unpaid Principal Balance | 1,355 |  | 1,355
Impaired loans without a valuation allowance, Unpaid Principal Balance | 2,866 |  | 3,604
Impaired loans, Valuation Allowance | 8 |  | 14
Impaired Financing Receivable, Average Recorded Investment [Abstract] |  |  |
Impaired loans with a valuation allowance, Average Outstanding Balance | 1,355 | 44 |
Impaired loans without a valuation allowance, Average Outstanding Balance | 3,235 | 6,087 |
Impaired Financing Receivable, Interest Income, Accrual Method [Abstract] |  |  |
Impaired loans with a valuation allowance, Interest Income Recognized | 22 | 0 |
Impaired loans without a valuation allowance, Interest Income Recognized | 7 | 70 |
Total residential real estate [Member] |  |  |
Impaired Financing Receivable, Recorded Investment [Abstract] |  |  |
Impaired loans, Outstanding Balance | 5,374 |  | 5,486
Impaired Financing Receivable, Unpaid Principal Balance [Abstract] |  |  |
Impaired loans, Unpaid Principal Balance | 6,102 |  | 6,215
Impaired loans, Valuation Allowance | 1,052 |  | 1,073
Impaired Financing Receivable, Average Recorded Investment [Abstract] |  |  |
Impaired loans, Average Outstanding Balance | 5,430 | 6,737 |
Impaired Financing Receivable, Interest Income, Accrual Method [Abstract] |  |  |
Impaired loans, Interest Income Recognized | 61 | 74 |
Residential real estate senior liens [Member] |  |  |
Impaired Financing Receivable, Recorded Investment [Abstract] |  |  |
Impaired loans with a valuation allowance, Outstanding Balance | 5,285 |  | 5,401
Impaired Financing Receivable, Unpaid Principal Balance [Abstract] |  |  |
Impaired loans with a valuation allowance, Unpaid Principal Balance | 5,713 |  | 5,830
Impaired loans, Valuation Allowance | 1,052 |  | 1,073
Impaired Financing Receivable, Average Recorded Investment [Abstract] |  |  |
Impaired loans with a valuation allowance, Average Outstanding Balance | 5,343 | 6,682 |
Impaired Financing Receivable, Interest Income, Accrual Method [Abstract] |  |  |
Impaired loans with a valuation allowance, Interest Income Recognized | 55 | 68 |
Residential real estate junior liens [Member] |  |  |
Impaired Financing Receivable, Average Recorded Investment [Abstract] |  |  |
Impaired loans with a valuation allowance, Average Outstanding Balance | 0 | 12 |
Impaired Financing Receivable, Interest Income, Accrual Method [Abstract] |  |  |
Impaired loans with a valuation allowance, Interest Income Recognized | 0 | 0 |
Residential real estate home equity lines of credit [Member] |  |  |
Impaired Financing Receivable, Recorded Investment [Abstract] |  |  |
Impaired loans without a valuation allowance, Outstanding Balance | 89 |  | 85
Impaired Financing Receivable, Unpaid Principal Balance [Abstract] |  |  |
Impaired loans without a valuation allowance, Unpaid Principal Balance | 389 |  | 385
Impaired Financing Receivable, Average Recorded Investment [Abstract] |  |  |
Impaired loans without a valuation allowance, Average Outstanding Balance | 87 | 43 |
Impaired Financing Receivable, Interest Income, Accrual Method [Abstract] |  |  |
Impaired loans without a valuation allowance, Interest Income Recognized | 6 | 6 |
Total Consumer [Member] |  |  |
Impaired Financing Receivable, Recorded Investment [Abstract] |  |  |
Impaired loans, Outstanding Balance | 3 |  | 0
Impaired Financing Receivable, Unpaid Principal Balance [Abstract] |  |  |
Impaired loans, Unpaid Principal Balance | 3 |  | 0
Impaired loans, Valuation Allowance | 0 |  | 0
Impaired Financing Receivable, Average Recorded Investment [Abstract] |  |  |
Impaired loans, Average Outstanding Balance | 2 | 9 |
Impaired Financing Receivable, Interest Income, Accrual Method [Abstract] |  |  |
Impaired loans, Interest Income Recognized | 0 | 0 |
Consumer secured [Member] |  |  |
Impaired Financing Receivable, Recorded Investment [Abstract] |  |  |
Impaired loans without a valuation allowance, Outstanding Balance | 3 |  | 0
Impaired Financing Receivable, Unpaid Principal Balance [Abstract] |  |  |
Impaired loans without a valuation allowance, Unpaid Principal Balance | 3 |  | $ 0
Impaired Financing Receivable, Average Recorded Investment [Abstract] |  |  |
Impaired loans without a valuation allowance, Average Outstanding Balance | 2 | 9 |
Impaired Financing Receivable, Interest Income, Accrual Method [Abstract] |  |  |
Impaired loans without a valuation allowance, Interest Income Recognized | $ 0 | $ 0 |

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