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Loans and ALLL (Summary of information pertaining to TDRs) (Details) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2019 USD ($) loan | Sep. 30, 2018 USD ($) loan | Sep. 30, 2019 USD ($) loan | Sep. 30, 2018 USD ($) loan
Financing Receivable, Modifications [Line Items] |  |  |  |
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment | $ 10,470 | $ 13,500 | $ 10,523 | $ 14,417
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method | $ 37 | $ 132 | $ 252 | $ 371
Number of Loans | loan | 1 | 8 | 6 | 34
Pre-Modification Recorded Investment | $ 25 | $ 1,426 | $ 2,043 | $ 7,671
Financing Receivable, Modifications, Post-Modification Recorded Investment | $ 25 | $ 1,426 | $ 2,043 | $ 7,647
Interest Rate Below Market Reduction [Member] |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of Loans | loan | 1 | 6 | 1 | 15
Pre-Modification Recorded Investment | $ 25 | $ 575 | $ 25 | $ 2,674
Below Market Interest Rate and Extension of Amortization Period [Member] |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of Loans | loan | 0 | 2 | 5 | 19
Pre-Modification Recorded Investment | $ 0 | $ 851 | $ 2,018 | $ 4,997
Commercial other [Member] |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment | 11 | 778 | 11 | 1,263
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method | 0 | 16 | $ 0 | $ 55
Number of Loans | loan |  |  | 2 | 4
Pre-Modification Recorded Investment |  |  | $ 184 | $ 1,360
Financing Receivable, Modifications, Post-Modification Recorded Investment |  |  | $ 184 | $ 1,360
Commercial other [Member] | Interest Rate Below Market Reduction [Member] |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of Loans | loan |  |  | 0 | 1
Pre-Modification Recorded Investment |  |  | $ 0 | $ 174
Commercial other [Member] | Below Market Interest Rate and Extension of Amortization Period [Member] |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of Loans | loan |  |  | 2 | 3
Pre-Modification Recorded Investment |  |  | $ 184 | $ 1,186
Agricultural other [Member] |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment | 1,292 | 324 | 659 | 108
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method | $ 11 | $ 45 | $ 20 | $ 45
Number of Loans | loan | 1 | 7 | 4 | 22
Pre-Modification Recorded Investment | $ 25 | $ 1,327 | $ 1,859 | $ 5,718
Financing Receivable, Modifications, Post-Modification Recorded Investment | $ 25 | $ 1,327 | $ 1,859 | $ 5,694
Agricultural other [Member] | Interest Rate Below Market Reduction [Member] |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of Loans | loan | 1 | 5 | 1 | 12
Pre-Modification Recorded Investment | $ 25 | $ 476 | $ 25 | $ 2,345
Agricultural other [Member] | Below Market Interest Rate and Extension of Amortization Period [Member] |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of Loans | loan | 0 | 2 | 3 | 10
Pre-Modification Recorded Investment | $ 0 | $ 851 | $ 1,834 | $ 3,373
Residential real estate senior liens [Member] |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment | 6,096 | 7,512 | 6,406 | 7,694
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method | $ 14 | $ 17 | $ 101 | $ 107
Number of Loans | loan | 0 | 1 | 0 | 8
Pre-Modification Recorded Investment | $ 0 | $ 99 | $ 0 | $ 593
Financing Receivable, Modifications, Post-Modification Recorded Investment | $ 0 | $ 99 | $ 0 | $ 593
Residential real estate senior liens [Member] | Interest Rate Below Market Reduction [Member] |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of Loans | loan | 0 | 1 | 0 | 2
Pre-Modification Recorded Investment | $ 0 | $ 99 | $ 0 | $ 155
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 | 0 | 0 | 6
Pre-Modification Recorded Investment | $ 0 | $ 0 | $ 0 | $ 438
Residential real estate junior liens [Member] |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment | 12 | 18 | 12 | 29
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method | $ 0 | $ 0 | $ 0 | $ 0

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