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Loans and ALLL (Summary of information pertaining to TDRs) (Details) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2020 USD ($) loan | Dec. 31, 2019 USD ($) loan
Financing Receivable, Modifications [Line Items] |  |
Number of Loans | loan | 18 | 11
Pre-Modification Recorded Investment | $ 8,554 | $ 4,491
Post-Modification Recorded Investment | $ 8,554 | $ 4,491
Commercial other [Member] |  |
Financing Receivable, Modifications [Line Items] |  |
Number of Loans | loan | 10 | 3
Pre-Modification Recorded Investment | $ 5,224 | $ 1,188
Post-Modification Recorded Investment | $ 5,224 | $ 1,188
Agricultural other [Member] |  |
Financing Receivable, Modifications [Line Items] |  |
Number of Loans | loan | 5 | 7
Pre-Modification Recorded Investment | $ 3,194 | $ 3,286
Post-Modification Recorded Investment | $ 3,194 | $ 3,286
Residential real estate senior liens [Member] |  |
Financing Receivable, Modifications [Line Items] |  |
Number of Loans | loan | 3 | 1
Pre-Modification Recorded Investment | $ 136 | $ 17
Post-Modification Recorded Investment | $ 136 | $ 17
Below Market Interest Rate and Extension of Amortization Period [Member] |  |
Financing Receivable, Modifications [Line Items] |  |
Number of Loans | loan | 16 | 9
Pre-Modification Recorded Investment | $ 7,567 | $ 3,302
Below Market Interest Rate and Extension of Amortization Period [Member] | Commercial other [Member] |  |
Financing Receivable, Modifications [Line Items] |  |
Number of Loans | loan | 8 | 3
Pre-Modification Recorded Investment | $ 4,237 | $ 1,188
Below Market Interest Rate and Extension of Amortization Period [Member] | Agricultural other [Member] |  |
Financing Receivable, Modifications [Line Items] |  |
Number of Loans | loan | 5 | 5
Pre-Modification Recorded Investment | $ 3,194 | $ 2,097
Below Market Interest Rate and Extension of Amortization Period [Member] | Residential real estate senior liens [Member] |  |
Financing Receivable, Modifications [Line Items] |  |
Number of Loans | loan | 3 | 1
Pre-Modification Recorded Investment | $ 136 | $ 17
Interest Rate Below Market Reduction [Member] |  |
Financing Receivable, Modifications [Line Items] |  |
Number of Loans | loan | 2 | 2
Pre-Modification Recorded Investment | $ 987 | $ 1,189
Interest Rate Below Market Reduction [Member] | Commercial other [Member] |  |
Financing Receivable, Modifications [Line Items] |  |
Number of Loans | loan | 2 | 0
Pre-Modification Recorded Investment | $ 987 | $ 0
Interest Rate Below Market Reduction [Member] | Agricultural other [Member] |  |
Financing Receivable, Modifications [Line Items] |  |
Number of Loans | loan | 0 | 2
Pre-Modification Recorded Investment | $ 0 | $ 1,189
Interest Rate Below Market Reduction [Member] | Residential real estate senior liens [Member] |  |
Financing Receivable, Modifications [Line Items] |  |
Number of Loans | loan | 0 | 0
Pre-Modification Recorded Investment | $ 0 | $ 0

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