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Loans and ALLL (Summary of recorded investment in loans by segments) (Details) - USD ($) $ in Thousands | Sep. 30, 2021 | Jun. 30, 2021 | Dec. 31, 2020 | Sep. 30, 2020 | Jun. 30, 2020 | Dec. 31, 2019
--- | --- | --- | --- | --- | --- | ---
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |
Individually evaluated for impairment, ALLL | $ 583 |  | $ 911 |  |  |
Collectively evaluated for impairment, ALLL | 8,510 |  | 8,833 |  |  |
Total, ALLL | 9,093 | $ 9,360 | 9,744 | $ 9,506 | $ 8,877 | $ 7,939
Individually evaluated for impairment, Loans | 29,668 |  | 27,936 |  |  |
Collectively evaluated for impairment, Loans | 1,218,890 |  | 1,210,375 |  |  |
Total | 1,248,558 |  | 1,238,311 |  |  |
Commercial [Member] |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |
Individually evaluated for impairment, ALLL | 21 |  | 84 |  |  |
Collectively evaluated for impairment, ALLL | 1,510 |  | 2,078 |  |  |
Total, ALLL | 1,531 | 2,311 | 2,162 | 1,945 | 2,121 | 1,914
Individually evaluated for impairment, Loans | 11,563 |  | 9,821 |  |  |
Collectively evaluated for impairment, Loans | 746,430 |  | 746,865 |  |  |
Total | 757,993 |  | 756,686 |  |  |
Agricultural [Member] |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |
Individually evaluated for impairment, ALLL | 0 |  | 56 |  |  |
Collectively evaluated for impairment, ALLL | 466 |  | 255 |  |  |
Total, ALLL | 466 | 248 | 311 | 342 | 356 | 634
Individually evaluated for impairment, Loans | 14,623 |  | 13,796 |  |  |
Collectively evaluated for impairment, Loans | 79,159 |  | 86,665 |  |  |
Total | 93,782 |  | 100,461 |  |  |
Residential Real Estate [Member] |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |
Individually evaluated for impairment, ALLL | 562 |  | 771 |  |  |
Collectively evaluated for impairment, ALLL | 195 |  | 592 |  |  |
Total, ALLL | 757 | 954 | 1,363 | 1,306 | 1,193 | 2,047
Individually evaluated for impairment, Loans | 3,482 |  | 4,319 |  |  |
Collectively evaluated for impairment, Loans | 318,138 |  | 303,224 |  |  |
Total | 321,620 |  | 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 | 849 |  | 798 |  |  |
Total, ALLL | 849 | 938 | 798 | 855 | 825 | 922
Individually evaluated for impairment, Loans | 0 |  | 0 |  |  |
Collectively evaluated for impairment, Loans | 75,163 |  | 73,621 |  |  |
Total | 75,163 |  | 73,621 |  |  |
Unallocated [Member] |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |
Individually evaluated for impairment, ALLL | 0 |  | 0 |  |  |
Collectively evaluated for impairment, ALLL | 5,490 |  | 5,110 |  |  |
Total, ALLL | $ 5,490 | $ 4,909 | $ 5,110 | $ 5,058 | $ 4,382 | $ 2,422

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