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Loans and ALLL (Summary of information pertaining to TDRs) (Details) $ in Thousands | 3 Months Ended
--- | ---
Mar. 31, 2020 USD ($) loan | Mar. 31, 2019 USD ($) loan
Financing Receivable, Modifications [Line Items] |  |
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment | $ 9,857 | $ 10,549
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method | $ 132 | $ 123
Number of Loans | loan | 6 | 3
Pre-Modification Recorded Investment | $ 1,649 | $ 670
Financing Receivable, Modifications, Post-Modification Recorded Investment | $ 1,649 | $ 670
Interest Rate Below Market Reduction [Member] |  |
Financing Receivable, Modifications [Line Items] |  |
Number of Loans | loan | 1 | 0
Pre-Modification Recorded Investment | $ 919 | $ 0
Below Market Interest Rate and Extension of Amortization Period [Member] |  |
Financing Receivable, Modifications [Line Items] |  |
Number of Loans | loan | 5 | 3
Pre-Modification Recorded Investment | $ 730 | $ 670
Commercial other [Member] |  |
Financing Receivable, Modifications [Line Items] |  |
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment | 460 | 12
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method | $ 6 | $ 0
Number of Loans | loan | 2 | 1
Pre-Modification Recorded Investment | $ 963 | $ 147
Financing Receivable, Modifications, Post-Modification Recorded Investment | $ 963 | $ 147
Commercial other [Member] | Interest Rate Below Market Reduction [Member] |  |
Financing Receivable, Modifications [Line Items] |  |
Number of Loans | loan | 1 | 0
Pre-Modification Recorded Investment | $ 919 | $ 0
Commercial other [Member] | Below Market Interest Rate and Extension of Amortization Period [Member] |  |
Financing Receivable, Modifications [Line Items] |  |
Number of Loans | loan | 1 | 1
Pre-Modification Recorded Investment | $ 44 | $ 147
Agricultural other [Member] |  |
Financing Receivable, Modifications [Line Items] |  |
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment | 1,355 | 44
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method | $ 22 | $ 0
Number of Loans | loan | 2 | 2
Pre-Modification Recorded Investment | $ 593 | $ 523
Financing Receivable, Modifications, Post-Modification Recorded Investment | $ 593 | $ 523
Agricultural other [Member] | Interest Rate Below Market Reduction [Member] |  |
Financing Receivable, Modifications [Line Items] |  |
Number of Loans | loan | 0 | 0
Pre-Modification Recorded Investment | $ 0 | $ 0
Agricultural other [Member] | Below Market Interest Rate and Extension of Amortization Period [Member] |  |
Financing Receivable, Modifications [Line Items] |  |
Number of Loans | loan | 2 | 2
Pre-Modification Recorded Investment | $ 593 | $ 523
Residential real estate senior liens [Member] |  |
Financing Receivable, Modifications [Line Items] |  |
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment | 5,343 | 6,682
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method | $ 55 | $ 68
Number of Loans | loan | 2 | 0
Pre-Modification Recorded Investment | $ 93 | $ 0
Financing Receivable, Modifications, Post-Modification Recorded Investment | $ 93 | $ 0
Residential real estate senior liens [Member] | Interest Rate Below Market Reduction [Member] |  |
Financing Receivable, Modifications [Line Items] |  |
Number of Loans | loan | 0 | 0
Pre-Modification Recorded Investment | $ 0 | $ 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 | 2 | 0
Pre-Modification Recorded Investment | $ 93 | $ 0
Residential real estate junior liens [Member] |  |
Financing Receivable, Modifications [Line Items] |  |
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment | 0 | 12
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method | $ 0 | $ 0

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