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Loans and ALLL (Summary of recorded investment in loans by segments) (Details) - USD ($) $ in Thousands | Sep. 30, 2020 | Jun. 30, 2020 | Dec. 31, 2019 | Sep. 30, 2019 | Jun. 30, 2019 | Dec. 31, 2018
--- | --- | --- | --- | --- | --- | ---
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |
Individually evaluated for impairment, ALLL | $ 869 |  | $ 1,114 |  |  |
Collectively evaluated for impairment, ALLL | 8,637 |  | 6,825 |  |  |
Total, ALLL | 9,506 | $ 8,877 | 7,939 | $ 8,169 | $ 8,037 | $ 8,375
Individually evaluated for impairment, Loans | 28,639 |  | 28,191 |  |  |
Collectively evaluated for impairment, Loans | 1,274,669 |  | 1,158,379 |  |  |
Total | 1,303,308 |  | 1,186,570 |  |  |
Commercial [Member] |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |
Individually evaluated for impairment, ALLL | 59 |  | 15 |  |  |
Collectively evaluated for impairment, ALLL | 1,886 |  | 1,899 |  |  |
Total, ALLL | 1,945 | 2,121 | 1,914 | 2,060 | 2,080 | 2,563
Individually evaluated for impairment, Loans | 11,351 |  | 7,865 |  |  |
Collectively evaluated for impairment, Loans | 809,751 |  | 693,076 |  |  |
Total | 821,102 |  | 700,941 |  |  |
Agricultural [Member] |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |
Individually evaluated for impairment, ALLL | 67 |  | 26 |  |  |
Collectively evaluated for impairment, ALLL | 275 |  | 608 |  |  |
Total, ALLL | 342 | 356 | 634 | 555 | 612 | 775
Individually evaluated for impairment, Loans | 12,903 |  | 14,840 |  |  |
Collectively evaluated for impairment, Loans | 89,360 |  | 102,080 |  |  |
Total | 102,263 |  | 116,920 |  |  |
Residential Real Estate [Member] |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |
Individually evaluated for impairment, ALLL | 743 |  | 1,073 |  |  |
Collectively evaluated for impairment, ALLL | 563 |  | 974 |  |  |
Total, ALLL | 1,306 | 1,193 | 2,047 | 1,869 | 1,882 | 1,992
Individually evaluated for impairment, Loans | 4,385 |  | 5,486 |  |  |
Collectively evaluated for impairment, Loans | 300,174 |  | 293,083 |  |  |
Total | 304,559 |  | 298,569 |  |  |
Total Consumer [Member] |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |
Individually evaluated for impairment, ALLL | 0 |  | 0 |  |  |
Collectively evaluated for impairment, ALLL | 855 |  | 922 |  |  |
Total, ALLL | 855 | 825 | 922 | 1,020 | 927 | 857
Individually evaluated for impairment, Loans | 0 |  | 0 |  |  |
Collectively evaluated for impairment, Loans | 75,384 |  | 70,140 |  |  |
Total | 75,384 |  | 70,140 |  |  |
Unallocated [Member] |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |
Individually evaluated for impairment, ALLL | 0 |  | 0 |  |  |
Collectively evaluated for impairment, ALLL | 5,058 |  | 2,422 |  |  |
Total, ALLL | $ 5,058 | $ 4,382 | $ 2,422 | $ 2,665 | $ 2,536 | $ 2,188

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