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Loans and ALLL (Summary of information pertaining to impaired loans) (Details) - USD ($) $ in Thousands | 3 Months Ended |
--- | --- | ---
Mar. 31, 2019 | Mar. 31, 2018 | Dec. 31, 2018
Impaired Financing Receivable, Recorded Investment [Abstract] |  |  |
Impaired loans with a valuation allowance, Outstanding Balance | $ 9,834 |  | $ 11,263
Impaired loans without a valuation allowance, Outstanding Balance | 20,199 |  | 19,836
Impaired loans, Outstanding Balance | 30,033 |  | 31,099
Impaired Financing Receivable, Unpaid Principal Balance [Abstract] |  |  |
Impaired loans with a valuation allowance, Unpaid Principal Balance | 10,507 |  | 11,960
Impaired loans without a valuation allowance, Unpaid Principal Balance | 20,573 |  | 20,439
Impaired loans, Unpaid Principal Balance | 31,080 |  | 32,399
Impaired loans, Valuation Allowance | 1,509 |  | 1,938
Impaired Financing Receivable, Average Recorded Investment [Abstract] |  |  |
Impaired loans with a valuation allowance, Average Outstanding Balance | 10,549 | $ 14,870 |
Impaired loans without a valuation allowance, Average Outstanding Balance | 20,019 | 14,007 |
Impaired loans, Average Outstanding Balance | 30,568 | 28,877 |
Impaired Financing Receivable, Interest Income, Accrual Method [Abstract] |  |  |
Impaired loans with a valuation allowance, Interest Income Recognized | 123 | 193 |
Impaired loans without a valuation allowance, Interest Income Recognized | 157 | 133 |
Impaired loans, Interest Income Recognized | 280 | 326 |
Total commercial [Member] |  |  |
Impaired Financing Receivable, Recorded Investment [Abstract] |  |  |
Impaired loans, Outstanding Balance | 9,456 |  | 9,899
Impaired Financing Receivable, Unpaid Principal Balance [Abstract] |  |  |
Impaired loans, Unpaid Principal Balance | 9,773 |  | 10,401
Impaired loans, Valuation Allowance | 94 |  | 443
Impaired Financing Receivable, Average Recorded Investment [Abstract] |  |  |
Impaired loans, Average Outstanding Balance | 9,678 | 9,888 |
Impaired Financing Receivable, Interest Income, Accrual Method [Abstract] |  |  |
Impaired loans, Interest Income Recognized | 123 | 167 |
Commercial real estate [Member] |  |  |
Impaired Financing Receivable, Recorded Investment [Abstract] |  |  |
Impaired loans with a valuation allowance, Outstanding Balance | 2,849 |  | 3,969
Impaired loans without a valuation allowance, Outstanding Balance | 3,780 |  | 2,794
Impaired Financing Receivable, Unpaid Principal Balance [Abstract] |  |  |
Impaired loans with a valuation allowance, Unpaid Principal Balance | 3,092 |  | 4,211
Impaired loans without a valuation allowance, Unpaid Principal Balance | 3,854 |  | 2,947
Impaired loans, Valuation Allowance | 89 |  | 437
Impaired Financing Receivable, Average Recorded Investment [Abstract] |  |  |
Impaired loans with a valuation allowance, Average Outstanding Balance | 3,409 | 5,018 |
Impaired loans without a valuation allowance, Average Outstanding Balance | 3,287 | 2,129 |
Impaired Financing Receivable, Interest Income, Accrual Method [Abstract] |  |  |
Impaired loans with a valuation allowance, Interest Income Recognized | 49 | 91 |
Impaired loans without a valuation allowance, Interest Income Recognized | 53 | 35 |
Commercial other [Member] |  |  |
Impaired Financing Receivable, Recorded Investment [Abstract] |  |  |
Impaired loans with a valuation allowance, Outstanding Balance | 11 |  | 12
Impaired loans without a valuation allowance, Outstanding Balance | 2,816 |  | 3,124
Impaired Financing Receivable, Unpaid Principal Balance [Abstract] |  |  |
Impaired loans with a valuation allowance, Unpaid Principal Balance | 11 |  | 12
Impaired loans without a valuation allowance, Unpaid Principal Balance | 2,816 |  | 3,231
Impaired loans, Valuation Allowance | 5 |  | 6
Impaired Financing Receivable, Average Recorded Investment [Abstract] |  |  |
Impaired loans with a valuation allowance, Average Outstanding Balance | 12 | 1,547 |
Impaired loans without a valuation allowance, Average Outstanding Balance | 2,970 | 1,194 |
Impaired Financing Receivable, Interest Income, Accrual Method [Abstract] |  |  |
Impaired loans with a valuation allowance, Interest Income Recognized | 0 | 24 |
Impaired loans without a valuation allowance, Interest Income Recognized | 21 | 17 |
Total agricultural [Member] |  |  |
Impaired Financing Receivable, Recorded Investment [Abstract] |  |  |
Impaired loans, Outstanding Balance | 13,989 |  | 14,298
Impaired Financing Receivable, Unpaid Principal Balance [Abstract] |  |  |
Impaired loans, Unpaid Principal Balance | 13,989 |  | 14,341
Impaired loans, Valuation Allowance | 118 |  | 132
Impaired Financing Receivable, Average Recorded Investment [Abstract] |  |  |
Impaired loans, Average Outstanding Balance | 14,144 | 11,034 |
Impaired Financing Receivable, Interest Income, Accrual Method [Abstract] |  |  |
Impaired loans, Interest Income Recognized | 83 | 80 |
Agricultural real estate [Member] |  |  |
Impaired Financing Receivable, Recorded Investment [Abstract] |  |  |
Impaired loans with a valuation allowance, Outstanding Balance | 388 |  | 392
Impaired loans without a valuation allowance, Outstanding Balance | 7,628 |  | 7,618
Impaired Financing Receivable, Unpaid Principal Balance [Abstract] |  |  |
Impaired loans with a valuation allowance, Unpaid Principal Balance | 388 |  | 392
Impaired loans without a valuation allowance, Unpaid Principal Balance | 7,628 |  | 7,618
Impaired loans, Valuation Allowance | 96 |  | 112
Impaired Financing Receivable, Average Recorded Investment [Abstract] |  |  |
Impaired loans with a valuation allowance, Average Outstanding Balance | 390 | 441 |
Impaired loans without a valuation allowance, Average Outstanding Balance | 7,623 | 7,998 |
Impaired Financing Receivable, Interest Income, Accrual Method [Abstract] |  |  |
Impaired loans with a valuation allowance, Interest Income Recognized | 6 | 4 |
Impaired loans without a valuation allowance, Interest Income Recognized | 7 | 40 |
Agricultural other [Member] |  |  |
Impaired Financing Receivable, Recorded Investment [Abstract] |  |  |
Impaired loans with a valuation allowance, Outstanding Balance | 44 |  | 44
Impaired loans without a valuation allowance, Outstanding Balance | 5,929 |  | 6,244
Impaired Financing Receivable, Unpaid Principal Balance [Abstract] |  |  |
Impaired loans with a valuation allowance, Unpaid Principal Balance | 44 |  | 44
Impaired loans without a valuation allowance, Unpaid Principal Balance | 5,929 |  | 6,287
Impaired loans, Valuation Allowance | 22 |  | 20
Impaired Financing Receivable, Average Recorded Investment [Abstract] |  |  |
Impaired loans with a valuation allowance, Average Outstanding Balance | 44 | 0 |
Impaired loans without a valuation allowance, Average Outstanding Balance | 6,087 | 2,595 |
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 | 70 | 36 |
Total residential real estate [Member] |  |  |
Impaired Financing Receivable, Recorded Investment [Abstract] |  |  |
Impaired loans, Outstanding Balance | 6,580 |  | 6,893
Impaired Financing Receivable, Unpaid Principal Balance [Abstract] |  |  |
Impaired loans, Unpaid Principal Balance | 7,310 |  | 7,648
Impaired loans, Valuation Allowance | 1,297 |  | 1,363
Impaired Financing Receivable, Average Recorded Investment [Abstract] |  |  |
Impaired loans, Average Outstanding Balance | 6,737 | 7,940 |
Impaired Financing Receivable, Interest Income, Accrual Method [Abstract] |  |  |
Impaired loans, Interest Income Recognized | 74 | 79 |
Residential real estate senior liens [Member] |  |  |
Impaired Financing Receivable, Recorded Investment [Abstract] |  |  |
Impaired loans with a valuation allowance, Outstanding Balance | 6,530 |  | 6,834
Impaired Financing Receivable, Unpaid Principal Balance [Abstract] |  |  |
Impaired loans with a valuation allowance, Unpaid Principal Balance | 6,960 |  | 7,289
Impaired loans, Valuation Allowance | 1,295 |  | 1,361
Impaired Financing Receivable, Average Recorded Investment [Abstract] |  |  |
Impaired loans with a valuation allowance, Average Outstanding Balance | 6,682 | 7,824 |
Impaired Financing Receivable, Interest Income, Accrual Method [Abstract] |  |  |
Impaired loans with a valuation allowance, Interest Income Recognized | 68 | 74 |
Residential real estate junior liens [Member] |  |  |
Impaired Financing Receivable, Recorded Investment [Abstract] |  |  |
Impaired loans with a valuation allowance, Outstanding Balance | 12 |  | 12
Impaired Financing Receivable, Unpaid Principal Balance [Abstract] |  |  |
Impaired loans with a valuation allowance, Unpaid Principal Balance | 12 |  | 12
Impaired loans, Valuation Allowance | 2 |  | 2
Impaired Financing Receivable, Average Recorded Investment [Abstract] |  |  |
Impaired loans with a valuation allowance, Average Outstanding Balance | 12 | 40 |
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 | 38 |  | 47
Impaired Financing Receivable, Unpaid Principal Balance [Abstract] |  |  |
Impaired loans without a valuation allowance, Unpaid Principal Balance | 338 |  | 347
Impaired Financing Receivable, Average Recorded Investment [Abstract] |  |  |
Impaired loans without a valuation allowance, Average Outstanding Balance | 43 | 76 |
Impaired Financing Receivable, Interest Income, Accrual Method [Abstract] |  |  |
Impaired loans without a valuation allowance, Interest Income Recognized | 6 | 5 |
Total Consumer [Member] |  |  |
Impaired Financing Receivable, Recorded Investment [Abstract] |  |  |
Impaired loans, Outstanding Balance | 8 |  | 9
Impaired Financing Receivable, Unpaid Principal Balance [Abstract] |  |  |
Impaired loans, Unpaid Principal Balance | 8 |  | 9
Impaired loans, Valuation Allowance | 0 |  | 0
Impaired Financing Receivable, Average Recorded Investment [Abstract] |  |  |
Impaired loans, Average Outstanding Balance | 9 | 15 |
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 | 8 |  | 9
Impaired Financing Receivable, Unpaid Principal Balance [Abstract] |  |  |
Impaired loans without a valuation allowance, Unpaid Principal Balance | 8 |  | $ 9
Impaired Financing Receivable, Average Recorded Investment [Abstract] |  |  |
Impaired loans without a valuation allowance, Average Outstanding Balance | 9 | 15 |
Impaired Financing Receivable, Interest Income, Accrual Method [Abstract] |  |  |
Impaired loans without a valuation allowance, Interest Income Recognized | $ 0 | $ 0 |

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