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Loans and ALLL (Summary of recorded investment in loans by segments) (Details) - USD ($) $ in Thousands | Jun. 30, 2021 | Mar. 31, 2021 | Dec. 31, 2020 | Jun. 30, 2020 | Mar. 31, 2020 | Dec. 31, 2019
--- | --- | --- | --- | --- | --- | ---
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |
Individually evaluated for impairment, ALLL | $ 1,201 |  | $ 911 |  |  |
Collectively evaluated for impairment, ALLL | 8,159 |  | 8,833 |  |  |
Total, ALLL | 9,360 | $ 9,271 | 9,744 | $ 8,877 | $ 8,697 | $ 7,939
Individually evaluated for impairment, Loans | 30,535 |  | 27,936 |  |  |
Collectively evaluated for impairment, Loans | 1,176,128 |  | 1,210,375 |  |  |
Total | 1,206,663 |  | 1,238,311 |  |  |
Commercial [Member] |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |
Individually evaluated for impairment, ALLL | 541 |  | 84 |  |  |
Collectively evaluated for impairment, ALLL | 1,770 |  | 2,078 |  |  |
Total, ALLL | 2,311 | 1,699 | 2,162 | 2,121 | 2,375 | 1,914
Individually evaluated for impairment, Loans | 12,004 |  | 9,821 |  |  |
Collectively evaluated for impairment, Loans | 711,884 |  | 746,865 |  |  |
Total | 723,888 |  | 756,686 |  |  |
Agricultural [Member] |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |
Individually evaluated for impairment, ALLL | 3 |  | 56 |  |  |
Collectively evaluated for impairment, ALLL | 245 |  | 255 |  |  |
Total, ALLL | 248 | 230 | 311 | 356 | 490 | 634
Individually evaluated for impairment, Loans | 14,843 |  | 13,796 |  |  |
Collectively evaluated for impairment, Loans | 80,354 |  | 86,665 |  |  |
Total | 95,197 |  | 100,461 |  |  |
Residential Real Estate [Member] |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |
Individually evaluated for impairment, ALLL | 657 |  | 771 |  |  |
Collectively evaluated for impairment, ALLL | 297 |  | 592 |  |  |
Total, ALLL | 954 | 1,163 | 1,363 | 1,193 | 1,717 | 2,047
Individually evaluated for impairment, Loans | 3,688 |  | 4,319 |  |  |
Collectively evaluated for impairment, Loans | 308,879 |  | 303,224 |  |  |
Total | 312,567 |  | 307,543 |  |  |
Total Consumer [Member] |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |
Individually evaluated for impairment, ALLL | 0 |  | 0 |  |  |
Collectively evaluated for impairment, ALLL | 938 |  | 798 |  |  |
Total, ALLL | 938 | 956 | 798 | 825 | 961 | 922
Individually evaluated for impairment, Loans | 0 |  | 0 |  |  |
Collectively evaluated for impairment, Loans | 75,011 |  | 73,621 |  |  |
Total | 75,011 |  | 73,621 |  |  |
Unallocated [Member] |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |
Individually evaluated for impairment, ALLL | 0 |  | 0 |  |  |
Collectively evaluated for impairment, ALLL | 4,909 |  | 5,110 |  |  |
Total, ALLL | $ 4,909 | $ 5,223 | $ 5,110 | $ 4,382 | $ 3,154 | $ 2,422

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