Loans, Impaired Financing Receivable (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	$ 16,050		$ 14,803
Recorded Investment With No Allowance	11,570		10,882
Recorded Investment With Allowance	1,668		1,402
Total Recorded Investment	13,238		12,284
Related Allowance	475		355
Average Recorded Investment	12,852	$ 9,064
Interest Income Recognized	100	41
Interest Income Recognized Cash Basis	1	1
Real Estate Loans [Member] \| Mortgages [Member]
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	504		281
Recorded Investment With No Allowance	115		114
Recorded Investment With Allowance	348		129
Total Recorded Investment	463		243
Related Allowance	38		26
Average Recorded Investment	391	188
Interest Income Recognized	4	2
Interest Income Recognized Cash Basis	0	0
Real Estate Loans [Member] \| Home Equity [Member]
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	60		61
Recorded Investment With No Allowance	0		0
Recorded Investment With Allowance	60		61
Total Recorded Investment	60		61
Related Allowance	11		11
Average Recorded Investment	60	124
Interest Income Recognized	1	1
Interest Income Recognized Cash Basis	0	0
Real Estate Loans [Member] \| Commercial [Member]
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	8,922		8,654
Recorded Investment With No Allowance	6,064		5,843
Recorded Investment With Allowance	209		225
Total Recorded Investment	6,273		6,068
Related Allowance	103		62
Average Recorded Investment	6,179	6,023
Interest Income Recognized	26	13
Interest Income Recognized Cash Basis	0	0
Real Estate Loans [Member] \| Agricultural [Member]
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	165		167
Recorded Investment With No Allowance	165		167
Recorded Investment With Allowance	0		0
Total Recorded Investment	165		167
Related Allowance	0		0
Average Recorded Investment	165	0
Interest Income Recognized	2	0
Interest Income Recognized Cash Basis	0	0
Real Estate Loans [Member] \| Construction [Member]
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	0		0
Recorded Investment With No Allowance	0		0
Recorded Investment With Allowance	0		0
Total Recorded Investment	0		0
Related Allowance	0		0
Average Recorded Investment	0	0
Interest Income Recognized	0	0
Interest Income Recognized Cash Basis	0	0
Consumer [Member]
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	0		0
Recorded Investment With No Allowance	0		0
Recorded Investment With Allowance	0		0
Total Recorded Investment	0		0
Related Allowance	0		0
Average Recorded Investment	0	0
Interest Income Recognized	0	0
Interest Income Recognized Cash Basis	0	0
Other Commercial Loans [Member]
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	6,295		5,535
Recorded Investment With No Allowance	5,122		4,653
Recorded Investment With Allowance	1,051		987
Total Recorded Investment	6,173		5,640
Related Allowance	323		256
Average Recorded Investment	5,952	2,729
Interest Income Recognized	66	25
Interest Income Recognized Cash Basis	1	1
Other Agricultural Loans [Member]
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	104		105
Recorded Investment With No Allowance	104		105
Recorded Investment With Allowance	0		0
Total Recorded Investment	104		105
Related Allowance	0		0
Average Recorded Investment	105	0
Interest Income Recognized	1	0
Interest Income Recognized Cash Basis	0	0
State and Political Subdivision Loans [Member]
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	0		0
Recorded Investment With No Allowance	0		0
Recorded Investment With Allowance	0		0
Total Recorded Investment	0		0
Related Allowance	0		$ 0
Average Recorded Investment	0	0
Interest Income Recognized	0	0
Interest Income Recognized Cash Basis	$ 0	$ 0

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- Definition

Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=49124121&loc=d3e5212-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=49124121&loc=d3e5258-111524

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- Definition

Amount of interest income recognized that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

+ References

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- Definition

Amount of interest income recognized on a cash-basis method of accounting that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

+ References

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Amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 14A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=49124121&loc=SL6953550-111524

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Amount of allowance for credit losses related to recorded investment.

+ References

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Amount of unpaid principal balance of impaired financing receivables with related allowance for credit losses and without related allowance for credit losses.

+ References

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- Definition

Amount of investment in impaired financing receivables for which there is no related allowance for credit losses.

+ References

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Amount of investment in impaired financing receivables for which there is a related allowance for credit losses.

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