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Loans and ALLL (Summary of information pertaining to TDRs) (Details) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2019 USD ($) loan | Jun. 30, 2018 USD ($) loan | Jun. 30, 2019 USD ($) loan | Jun. 30, 2018 USD ($) loan
Financing Receivable, Modifications [Line Items] |  |  |  |
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment | $ 10,551 | $ 14,885 | $ 10,550 | $ 14,877
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method | $ 92 | $ 46 | $ 215 | $ 239
Number of Loans | loan | 2 | 19 | 5 | 26
Pre-Modification Recorded Investment | $ 1,348 | $ 3,762 | $ 2,018 | $ 6,244
Financing Receivable, Modifications, Post-Modification Recorded Investment | $ 1,348 | $ 3,738 | $ 2,018 | $ 6,221
Interest Rate Below Market Reduction [Member] |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of Loans | loan | 0 | 7 | 0 | 9
Pre-Modification Recorded Investment | $ 0 | $ 1,826 | $ 0 | $ 2,098
Below Market Interest Rate and Extension of Amortization Period [Member] |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of Loans | loan | 2 | 12 | 5 | 17
Pre-Modification Recorded Investment | $ 1,348 | $ 1,936 | $ 2,018 | $ 4,146
Commercial other [Member] |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment | 11 | 1,463 | 11 | 1,505
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method | $ 0 | $ 15 | $ 0 | $ 39
Number of Loans | loan | 1 | 1 | 2 | 4
Pre-Modification Recorded Investment | $ 37 | $ 105 | $ 184 | $ 1,360
Financing Receivable, Modifications, Post-Modification Recorded Investment | $ 37 | $ 105 | $ 184 | $ 1,360
Commercial other [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 | $ 174
Commercial other [Member] | Below Market Interest Rate and Extension of Amortization Period [Member] |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of Loans | loan | 1 | 1 | 2 | 3
Pre-Modification Recorded Investment | $ 37 | $ 105 | $ 184 | $ 1,186
Agricultural other [Member] |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment | 641 | 0 | 343 | 0
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method | $ 9 | $ 0 | $ 9 | $ 0
Number of Loans | loan | 1 | 13 | 3 | 15
Pre-Modification Recorded Investment | $ 1,311 | $ 3,330 | $ 1,834 | $ 4,391
Financing Receivable, Modifications, Post-Modification Recorded Investment | $ 1,311 | $ 3,306 | $ 1,834 | $ 4,368
Agricultural other [Member] | Interest Rate Below Market Reduction [Member] |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of Loans | loan | 0 | 6 | 0 | 7
Pre-Modification Recorded Investment | $ 0 | $ 1,770 | $ 0 | $ 1,868
Agricultural other [Member] | Below Market Interest Rate and Extension of Amortization Period [Member] |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of Loans | loan | 1 | 7 | 3 | 8
Pre-Modification Recorded Investment | $ 1,311 | $ 1,560 | $ 1,834 | $ 2,523
Residential real estate senior liens [Member] |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment | 6,439 | 7,747 | 6,561 | 7,785
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method | $ 19 | $ 16 | $ 87 | $ 90
Number of Loans | loan | 0 | 5 | 0 | 7
Pre-Modification Recorded Investment | $ 0 | $ 327 | $ 0 | $ 493
Financing Receivable, Modifications, Post-Modification Recorded Investment | $ 0 | $ 327 | $ 0 | $ 493
Residential real estate senior liens [Member] | Interest Rate Below Market Reduction [Member] |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of Loans | loan | 0 | 1 | 0 | 1
Pre-Modification Recorded Investment | $ 0 | $ 56 | $ 0 | $ 56
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 | 4 | 0 | 6
Pre-Modification Recorded Investment | $ 0 | $ 271 | $ 0 | $ 437
Residential real estate junior liens [Member] |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment | 12 | 30 | 12 | 35
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method | $ 0 | $ 0 | $ 0 | $ 0

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