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Loans and ALLL (Summary of changes in ALLL by segments) (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Loans and Leases Receivable, Allowance | $ 7,939 | $ 8,375 |
Summary of changes in the ALLL and the recorded investment in loans by segments |  |  |
Allowance for loan losses, Beginning Balance | 8,375 | 7,700 |
Allowance for loan losses, Charge-offs | (948) | (1,101) |
Allowance for loan losses, Recoveries | 482 | 798 |
Allowance for loan losses, Provision for loan losses | 30 | 978 | $ 253
Allowance for loan losses, Ending Balance | 7,939 | 8,375 | 7,700
Commercial [Member] |  |  |
Summary of changes in the ALLL and the recorded investment in loans by segments |  |  |
Allowance for loan losses, Beginning Balance | 2,563 | 1,706 |
Allowance for loan losses, Charge-offs | (143) | (575) |
Allowance for loan losses, Recoveries | 123 | 325 |
Allowance for loan losses, Provision for loan losses | (629) | 1,107 |
Allowance for loan losses, Ending Balance | 1,914 | 2,563 | 1,706
Agricultural [Member] |  |  |
Summary of changes in the ALLL and the recorded investment in loans by segments |  |  |
Allowance for loan losses, Beginning Balance | 775 | 611 |
Allowance for loan losses, Charge-offs | (240) | (51) |
Allowance for loan losses, Recoveries | 3 | 3 |
Allowance for loan losses, Provision for loan losses | 96 | 212 |
Allowance for loan losses, Ending Balance | 634 | 775 | 611
Residential Real Estate [Member] |  |  |
Summary of changes in the ALLL and the recorded investment in loans by segments |  |  |
Allowance for loan losses, Beginning Balance | 1,992 | 2,563 |
Allowance for loan losses, Charge-offs | (99) | (151) |
Allowance for loan losses, Recoveries | 189 | 261 |
Allowance for loan losses, Provision for loan losses | (35) | (681) |
Allowance for loan losses, Ending Balance | 2,047 | 1,992 | 2,563
Consumer [Member] |  |  |
Summary of changes in the ALLL and the recorded investment in loans by segments |  |  |
Allowance for loan losses, Beginning Balance | 857 | 900 |
Allowance for loan losses, Charge-offs | (466) | (324) |
Allowance for loan losses, Recoveries | 167 | 209 |
Allowance for loan losses, Provision for loan losses | 364 | 72 |
Allowance for loan losses, Ending Balance | 922 | 857 | 900
Unallocated [Member] |  |  |
Summary of changes in the ALLL and the recorded investment in loans by segments |  |  |
Allowance for loan losses, Beginning Balance | 2,188 | 1,920 |
Allowance for loan losses, Charge-offs | 0 | 0 |
Allowance for loan losses, Recoveries | 0 | 0 |
Allowance for loan losses, Provision for loan losses | 234 | 268 |
Allowance for loan losses, Ending Balance | $ 2,422 | $ 2,188 | $ 1,920

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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. + References No definition available. + Details
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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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- Definition Amount of recovery of financing receivables doubtful of collection that were previously charged off. + 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)(4) -URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524 + Details
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- Definition Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.7(d)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (b)(1)(ii) -URI http://asc.fasb.org/extlink&oid=82894903&loc=d3e15032-111544 Reference 4: 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 Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section S99 -Paragraph 4 -Subparagraph (SAB Topic 6.L.1) -URI http://asc.fasb.org/extlink&oid=27010918&loc=d3e74567-122707 + Details
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