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Loans and ALLL (Summary of information pertaining to TDRs) (Details) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2018 USD ($) loan | Sep. 30, 2017 USD ($) loan | Sep. 30, 2018 USD ($) loan | Sep. 30, 2017 USD ($) loan
Financing Receivable, Modifications [Line Items] |  |  |  |
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment | $ 13,500 | $ 14,746 | $ 14,417 | $ 14,627
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method | $ 132 | $ 176 | $ 371 | $ 547
Number of Loans | loan | 8 | 5 | 34 | 19
Pre-Modification Recorded Investment | $ 1,426 | $ 1,564 | $ 7,671 | $ 7,585
Financing Receivable, Modifications, Post-Modification Recorded Investment | $ 1,426 | $ 1,564 | $ 7,647 | $ 7,585
Interest Rate Below Market Reduction [Member] |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of Loans | loan | 6 | 0 | 15 | 5
Pre-Modification Recorded Investment | $ 575 | $ 0 | $ 2,674 | $ 1,357
Below Market Interest Rate and Extension of Amortization Period [Member] |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of Loans | loan | 2 | 5 | 19 | 14
Pre-Modification Recorded Investment | $ 851 | $ 1,564 | $ 4,997 | $ 6,228
Commercial other [Member] |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment | 778 | 1,669 | 1,263 | 1,363
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method | $ 16 | $ 28 | $ 55 | $ 75
Number of Loans | loan | 0 | 3 | 4 | 6
Pre-Modification Recorded Investment | $ 0 | $ 1,385 | $ 1,360 | $ 1,698
Financing Receivable, Modifications, Post-Modification Recorded Investment | $ 0 | $ 1,385 | $ 1,360 | $ 1,698
Commercial other [Member] | Interest Rate Below Market Reduction [Member] |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of Loans | loan | 0 | 0 | 1 | 0
Pre-Modification Recorded Investment | $ 0 | $ 0 | $ 174 | $ 0
Commercial other [Member] | Below Market Interest Rate and Extension of Amortization Period [Member] |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of Loans | loan | 0 | 3 | 3 | 6
Pre-Modification Recorded Investment | $ 0 | $ 1,385 | $ 1,186 | $ 1,698
Agricultural other [Member] |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment | 324 | 0 | 108 | 22
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method | $ 45 | $ 0 | $ 45 | $ 0
Number of Loans | loan | 7 | 0 | 22 | 7
Pre-Modification Recorded Investment | $ 1,327 | $ 0 | $ 5,718 | $ 5,445
Financing Receivable, Modifications, Post-Modification Recorded Investment | $ 1,327 | $ 0 | $ 5,694 | $ 5,445
Agricultural other [Member] | Interest Rate Below Market Reduction [Member] |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of Loans | loan | 5 | 0 | 12 | 4
Pre-Modification Recorded Investment | $ 476 | $ 0 | $ 2,345 | $ 1,349
Agricultural other [Member] | Below Market Interest Rate and Extension of Amortization Period [Member] |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of Loans | loan | 2 | 0 | 10 | 3
Pre-Modification Recorded Investment | $ 851 | $ 0 | $ 3,373 | $ 4,096
Residential real estate senior liens [Member] |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment | 7,512 | 8,333 | 7,694 | 8,379
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method | $ 17 | $ 79 | $ 107 | $ 245
Number of Loans | loan | 1 | 2 | 8 | 5
Pre-Modification Recorded Investment | $ 99 | $ 179 | $ 593 | $ 434
Financing Receivable, Modifications, Post-Modification Recorded Investment | $ 99 | $ 179 | $ 593 | $ 434
Residential real estate senior liens [Member] | Interest Rate Below Market Reduction [Member] |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of Loans | loan | 1 | 0 | 2 | 0
Pre-Modification Recorded Investment | $ 99 | $ 0 | $ 155 | $ 0
Residential real estate senior liens [Member] | Below Market Interest Rate and Extension of Amortization Period [Member] |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of Loans | loan | 0 | 2 | 6 | 5
Pre-Modification Recorded Investment | $ 0 | $ 179 | $ 438 | $ 434
Residential real estate junior liens [Member] |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment | 18 | 73 | 29 | 75
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method | $ 0 | $ 1 | $ 0 | $ 2
Number of Loans | loan | 0 | 0 | 0 | 1
Pre-Modification Recorded Investment | $ 0 | $ 0 | $ 0 | $ 8
Financing Receivable, Modifications, Post-Modification Recorded Investment | $ 0 | $ 0 | $ 0 | $ 8
Residential real estate junior liens [Member] | Interest Rate Below Market Reduction [Member] |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of Loans | loan | 0 | 0 | 0 | 1
Pre-Modification Recorded Investment | $ 0 | $ 0 | $ 0 | $ 8
Residential real estate junior liens [Member] | Below Market Interest Rate and Extension of Amortization Period [Member] |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of Loans | loan | 0 | 0 | 0 | 0
Pre-Modification Recorded Investment | $ 0 | $ 0 | $ 0 | $ 0
Residential, Home Equity Line Of Credit, Financing Receivable [Member] |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment | 0 | 35 | 0 | 23
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method | $ 0 | $ 0 | $ 0 | $ 0
Total residential real estate [Member] |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of Loans | loan | 1 | 2 | 8 | 6
Pre-Modification Recorded Investment | $ 99 | $ 179 | $ 593 | $ 442
Financing Receivable, Modifications, Post-Modification Recorded Investment | $ 99 | $ 179 | $ 593 | $ 442
Total residential real estate [Member] | Interest Rate Below Market Reduction [Member] |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of Loans | loan | 1 | 0 | 2 | 1
Pre-Modification Recorded Investment | $ 99 | $ 0 | $ 155 | $ 8
Total residential real estate [Member] | Below Market Interest Rate and Extension of Amortization Period [Member] |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of Loans | loan | 0 | 2 | 6 | 5
Pre-Modification Recorded Investment | $ 0 | $ 179 | $ 438 | $ 434
Consumer Unsecured Financing Receivable [Member] |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of Loans | loan | 0 | 0 | 0 | 0
Pre-Modification Recorded Investment | $ 0 | $ 0 | $ 0 | $ 0
Financing Receivable, Modifications, Post-Modification Recorded Investment | $ 0 | $ 0 | $ 0 | $ 0
Consumer Unsecured Financing Receivable [Member] | Interest Rate Below Market Reduction [Member] |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of Loans | loan | 0 | 0 | 0 | 0
Pre-Modification Recorded Investment | $ 0 | $ 0 | $ 0 | $ 0
Consumer Unsecured Financing Receivable [Member] | Below Market Interest Rate and Extension of Amortization Period [Member] |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of Loans | loan | 0 | 0 | 0 | 0
Pre-Modification Recorded Investment | $ 0 | $ 0 | $ 0 | $ 0

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