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Loans and ALLL (Summary of recorded investment in loans by segments) (Details) - USD ($) $ in Thousands | Jun. 30, 2019 | Mar. 31, 2019 | Dec. 31, 2018 | Jun. 30, 2018 | Mar. 31, 2018 | Dec. 31, 2017
--- | --- | --- | --- | --- | --- | ---
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |  |  |  |
Individually evaluated for impairment, ALLL | $ 1,479 |  | $ 1,938 |  |  |
Collectively evaluated for impairment, ALLL | 6,558 |  | 6,437 |  |  |
Total, ALLL | 8,037 | $ 8,398 | 8,375 | $ 8,200 | $ 8,200 | $ 7,700
Individually evaluated for impairment, Loans | 28,897 |  | 31,099 |  |  |
Collectively evaluated for impairment, Loans | 1,147,725 |  | 1,097,608 |  |  |
Total | 1,176,622 |  | 1,128,707 |  |  |
Commercial [Member] |  |  |  |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |  |  |  |
Individually evaluated for impairment, ALLL | 58 |  | 443 |  |  |
Collectively evaluated for impairment, ALLL | 2,022 |  | 2,120 |  |  |
Total, ALLL | 2,080 | 2,248 | 2,563 | 2,197 | 1,840 | 1,706
Individually evaluated for impairment, Loans | 9,029 |  | 9,899 |  |  |
Collectively evaluated for impairment, Loans | 692,925 |  | 649,630 |  |  |
Total | 701,954 |  | 659,529 |  |  |
Agricultural [Member] |  |  |  |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |  |  |  |
Individually evaluated for impairment, ALLL | 123 |  | 132 |  |  |
Collectively evaluated for impairment, ALLL | 489 |  | 643 |  |  |
Total, ALLL | 612 | 775 | 775 | 982 | 1,224 | 611
Individually evaluated for impairment, Loans | 13,472 |  | 14,298 |  |  |
Collectively evaluated for impairment, Loans | 106,891 |  | 112,863 |  |  |
Total | 120,363 |  | 127,161 |  |  |
Residential Real Estate [Member] |  |  |  |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |  |  |  |
Individually evaluated for impairment, ALLL | 1,298 |  | 1,363 |  |  |
Collectively evaluated for impairment, ALLL | 584 |  | 629 |  |  |
Total, ALLL | 1,882 | 2,305 | 1,992 | 2,167 | 2,482 | 2,563
Individually evaluated for impairment, Loans | 6,389 |  | 6,893 |  |  |
Collectively evaluated for impairment, Loans | 276,896 |  | 268,450 |  |  |
Total | 283,285 |  | 275,343 |  |  |
Total Consumer [Member] |  |  |  |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |  |  |  |
Individually evaluated for impairment, ALLL | 0 |  | 0 |  |  |
Collectively evaluated for impairment, ALLL | 927 |  | 857 |  |  |
Total, ALLL | 927 | 891 | 857 | 882 | 795 | 900
Individually evaluated for impairment, Loans | 7 |  | 9 |  |  |
Collectively evaluated for impairment, Loans | 71,013 |  | 66,665 |  |  |
Total | 71,020 |  | 66,674 |  |  |
Unallocated [Member] |  |  |  |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |  |  |  |
Individually evaluated for impairment, ALLL | 0 |  | 0 |  |  |
Collectively evaluated for impairment, ALLL | 2,536 |  | 2,188 |  |  |
Total, ALLL | $ 2,536 | $ 2,179 | $ 2,188 | $ 1,972 | $ 1,859 | $ 1,920

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- Definition A valuation allowance for financing receivables that are expected to be uncollectible. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524 + Details
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