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Loans and ALLL (Summary of recorded investment in loans by segments) (Details) - USD ($) $ in Thousands | Mar. 31, 2021 | Dec. 31, 2020 | Mar. 31, 2020 | Dec. 31, 2019
--- | --- | --- | --- | ---
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |
Individually evaluated for impairment, ALLL | $ 1,380 | $ 911 |  |
Collectively evaluated for impairment, ALLL | 7,891 | 8,833 |  |
Total, ALLL | 9,271 | 9,744 | $ 8,697 | $ 7,939
Individually evaluated for impairment, Loans | 33,895 | 27,936 |  |
Collectively evaluated for impairment, Loans | 1,162,023 | 1,210,375 |  |
Total | 1,195,918 | 1,238,311 |  |
Commercial [Member] |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |
Individually evaluated for impairment, ALLL | 587 | 84 |  |
Collectively evaluated for impairment, ALLL | 1,112 | 2,078 |  |
Total, ALLL | 1,699 | 2,162 | 2,375 | 1,914
Individually evaluated for impairment, Loans | 14,300 | 9,821 |  |
Collectively evaluated for impairment, Loans | 711,240 | 746,865 |  |
Total | 725,540 | 756,686 |  |
Agricultural [Member] |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |
Individually evaluated for impairment, ALLL | 25 | 56 |  |
Collectively evaluated for impairment, ALLL | 205 | 255 |  |
Total, ALLL | 230 | 311 | 490 | 634
Individually evaluated for impairment, Loans | 15,459 | 13,796 |  |
Collectively evaluated for impairment, Loans | 76,170 | 86,665 |  |
Total | 91,629 | 100,461 |  |
Residential Real Estate [Member] |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |
Individually evaluated for impairment, ALLL | 768 | 771 |  |
Collectively evaluated for impairment, ALLL | 395 | 592 |  |
Total, ALLL | 1,163 | 1,363 | 1,717 | 2,047
Individually evaluated for impairment, Loans | 4,136 | 4,319 |  |
Collectively evaluated for impairment, Loans | 301,773 | 303,224 |  |
Total | 305,909 | 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 | 956 | 798 |  |
Total, ALLL | 956 | 798 | 961 | 922
Individually evaluated for impairment, Loans | 0 | 0 |  |
Collectively evaluated for impairment, Loans | 72,840 | 73,621 |  |
Total | 72,840 | 73,621 |  |
Unallocated [Member] |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |
Individually evaluated for impairment, ALLL | 0 | 0 |  |
Collectively evaluated for impairment, ALLL | 5,223 | 5,110 |  |
Total, ALLL | $ 5,223 | $ 5,110 | $ 3,154 | $ 2,422

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