Loans, Allowance for Loan Losses (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Allowance for loan losses [Roll Forward]
Balance, beginning of period	$ 3,121	$ 3,588
Provision charged to expenses	69	81
Losses charged off	(420)	(363)
Recoveries	67	64
Balance, end of period	2,837	3,370
Commercial and Industrial [Member]
Allowance for loan losses [Roll Forward]
Balance, beginning of period	129	175
Provision charged to expenses	1	(109)
Losses charged off	0	0
Recoveries	1	6
Balance, end of period	131	72
Commercial Secured By Real Estate [Member]
Allowance for loan losses [Roll Forward]
Balance, beginning of period	1,990	2,520
Provision charged to expenses	(37)	213
Losses charged off	(313)	(203)
Recoveries	0	0
Balance, end of period	1,640	2,530
Residential Real Estate [Member]
Allowance for loan losses [Roll Forward]
Balance, beginning of period	926	826
Provision charged to expenses	64	(25)
Losses charged off	(82)	(119)
Recoveries	26	21
Balance, end of period	934	703
Consumer [Member]
Allowance for loan losses [Roll Forward]
Balance, beginning of period	63	66
Provision charged to expenses	(29)	(3)
Losses charged off	(11)	(23)
Recoveries	31	24
Balance, end of period	54	64
Agricultural [Member]
Allowance for loan losses [Roll Forward]
Balance, beginning of period	11	0
Provision charged to expenses	66	0
Losses charged off	0	0
Recoveries	0	0
Balance, end of period	77	0
Other [Member]
Allowance for loan losses [Roll Forward]
Balance, beginning of period	2	1
Provision charged to expenses	4	5
Losses charged off	(14)	(18)
Recoveries	9	13
Balance, end of period	$ 1	$ 1

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

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)(1)

-URI http://asc.fasb.org/extlink&oid=49124121&loc=SL6953423-111524

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- Definition

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

+ 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)(4)

-URI http://asc.fasb.org/extlink&oid=49124121&loc=SL6953423-111524

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- Definition

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

+ 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)(3)

-URI http://asc.fasb.org/extlink&oid=49124121&loc=SL6953423-111524

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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 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3602-108585

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 310

-SubTopic 10

-Section 50

-Paragraph 11B

-Subparagraph (c)(2)

-URI http://asc.fasb.org/extlink&oid=49124121&loc=SL6953423-111524

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