Loans and ALLL (Summary of changes in ALLL by segments) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Summary of changes in the ALLL and the recorded investment in loans by segments
Allowance for loan losses, Beginning Balance	$ 7,939	$ 8,375
Allowance for loan losses, Charge-offs	(158)	(138)
Allowance for loan losses, Recoveries	128	127
Allowance for loan losses, Provision for loan losses	788	34
Allowance for loan losses, Ending Balance	8,697	8,398
Commercial [Member]
Summary of changes in the ALLL and the recorded investment in loans by segments
Allowance for loan losses, Beginning Balance	1,914	2,563
Allowance for loan losses, Charge-offs	(4)	(8)
Allowance for loan losses, Recoveries	22	51
Allowance for loan losses, Provision for loan losses	443	(358)
Allowance for loan losses, Ending Balance	2,375	2,248
Agricultural [Member]
Summary of changes in the ALLL and the recorded investment in loans by segments
Allowance for loan losses, Beginning Balance	634	775
Allowance for loan losses, Charge-offs	(16)	0
Allowance for loan losses, Recoveries	33	1
Allowance for loan losses, Provision for loan losses	(161)	(1)
Allowance for loan losses, Ending Balance	490	775
Residential Real Estate [Member]
Summary of changes in the ALLL and the recorded investment in loans by segments
Allowance for loan losses, Beginning Balance	2,047	1,992
Allowance for loan losses, Charge-offs	(15)	(2)
Allowance for loan losses, Recoveries	27	27
Allowance for loan losses, Provision for loan losses	(342)	288
Allowance for loan losses, Ending Balance	1,717	2,305
Consumer Portfolio Segment [Member]
Summary of changes in the ALLL and the recorded investment in loans by segments
Allowance for loan losses, Beginning Balance	922	857
Allowance for loan losses, Charge-offs	(123)	(128)
Allowance for loan losses, Recoveries	46	48
Allowance for loan losses, Provision for loan losses	116	114
Allowance for loan losses, Ending Balance	961	891
Unallocated [Member]
Summary of changes in the ALLL and the recorded investment in loans by segments
Allowance for loan losses, Beginning Balance	2,422	2,188
Allowance for loan losses, Charge-offs	0	0
Allowance for loan losses, Recoveries	0	0
Allowance for loan losses, Provision for loan losses	732	(9)
Allowance for loan losses, Ending Balance	$ 3,154	$ 2,179

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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A valuation allowance for financing receivables that are expected to be uncollectible.

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Amount of recovery of financing receivables doubtful of collection that were previously charged off.

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Amount of direct write-downs of financing receivables charged against the allowance.

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Amount of expense related loan transactions, lease transactions, credit loss from transactions other than loan and lease transactions, and other loss based on assessment of uncollectability from the counterparty to reduce the account to their net realizable value.

+ 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)(2)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.11)
-URI http://asc.fasb.org/extlink&oid=114873765&loc=SL114874048-224260

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585

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