Loans and ALLL (Summary of changes in ALLL by segments) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Summary of changes in the ALLL and the recorded investment in loans by segments
Allowance for loan losses, Beginning Balance	$ 7,500	$ 9,600	$ 7,400	$ 10,100
Allowance for loan losses, Charge-offs	(208)	(296)	(549)	(456)
Allowance for loan losses, Recoveries	296	231	581	617
Allowance for loan losses, Provision for loan losses	12	(535)	168	(1,261)
Allowance for loan losses, Ending Balance	7,600	9,000	7,600	9,000
Commercial [Member]
Summary of changes in the ALLL and the recorded investment in loans by segments
Allowance for loan losses, Beginning Balance	2,421	3,808	2,171	3,821
Allowance for loan losses, Charge-offs	(32)	(11)	(48)	(28)
Allowance for loan losses, Recoveries	189	106	278	319
Allowance for loan losses, Provision for loan losses	(459)	(421)	(282)	(630)
Allowance for loan losses, Ending Balance	2,119	3,482	2,119	3,482
Agricultural [Member]
Summary of changes in the ALLL and the recorded investment in loans by segments
Allowance for loan losses, Beginning Balance	336	206	329	216
Allowance for loan losses, Charge-offs	0	0	0	0
Allowance for loan losses, Recoveries	0	0	92	72
Allowance for loan losses, Provision for loan losses	198	157	113	75
Allowance for loan losses, Ending Balance	534	363	534	363
Residential Real Estate [Member]
Summary of changes in the ALLL and the recorded investment in loans by segments
Allowance for loan losses, Beginning Balance	3,130	3,728	3,330	4,235
Allowance for loan losses, Charge-offs	(128)	(205)	(369)	(255)
Allowance for loan losses, Recoveries	45	86	95	119
Allowance for loan losses, Provision for loan losses	83	(97)	74	(587)
Allowance for loan losses, Ending Balance	3,130	3,512	3,130	3,512
Consumer [Member]
Summary of changes in the ALLL and the recorded investment in loans by segments
Allowance for loan losses, Beginning Balance	540	711	522	645
Allowance for loan losses, Charge-offs	(48)	(80)	(132)	(173)
Allowance for loan losses, Recoveries	62	39	116	107
Allowance for loan losses, Provision for loan losses	(13)	(79)	35	12
Allowance for loan losses, Ending Balance	541	591	541	591
Unallocated [Member]
Summary of changes in the ALLL and the recorded investment in loans by segments
Allowance for loan losses, Beginning Balance	1,073	1,147	1,048	1,183
Allowance for loan losses, Charge-offs	0	0	0	0
Allowance for loan losses, Recoveries	0	0	0	0
Allowance for loan losses, Provision for loan losses	203	(95)	228	(131)
Allowance for loan losses, Ending Balance	$ 1,276	$ 1,052	$ 1,276	$ 1,052

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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- Definition

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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- Definition

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

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- Definition

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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=49124121&loc=SL6953423-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.11)
-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3602-108585

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