Loans, Impaired Financing Receivable (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	$ 14,330		$ 14,330		$ 14,803
Recorded Investment With No Allowance	10,505		10,505		10,882
Recorded Investment With Allowance	1,459		1,459		1,402
Total Recorded Investment	11,964		11,964		12,284
Related Allowance	482		482		355
Average Recorded Investment	11,943	$ 7,995	12,556	$ 8,584
Interest Income Recognized	92	36	297	123
Interest Income Recognized Cash Basis	2	1	5	9
Real Estate Loans [Member] \| Mortgages [Member]
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	959		959		281
Recorded Investment With No Allowance	574		574		114
Recorded Investment With Allowance	337		337		129
Total Recorded Investment	911		911		243
Related Allowance	28		28		26
Average Recorded Investment	607	269	486	239
Interest Income Recognized	1	4	10	8
Interest Income Recognized Cash Basis	0	0	0	5
Real Estate Loans [Member] \| Home Equity [Member]
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	58		58		61
Recorded Investment With No Allowance	0		0		0
Recorded Investment With Allowance	58		58		61
Total Recorded Investment	58		58		61
Related Allowance	11		11		11
Average Recorded Investment	58	62	59	97
Interest Income Recognized	1	1	3	3
Interest Income Recognized Cash Basis	0	0	0	0
Real Estate Loans [Member] \| Commercial [Member]
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	7,722		7,722		8,654
Recorded Investment With No Allowance	5,437		5,437		5,843
Recorded Investment With Allowance	130		130		225
Total Recorded Investment	5,567		5,567		6,068
Related Allowance	46		46		62
Average Recorded Investment	5,980	5,462	6,088	5,728
Interest Income Recognized	35	14	87	46
Interest Income Recognized Cash Basis	0	0	0	0
Real Estate Loans [Member] \| Agricultural [Member]
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	0		0		167
Recorded Investment With No Allowance	0		0		167
Recorded Investment With Allowance	0		0		0
Total Recorded Investment	0		0		167
Related Allowance	0		0		0
Average Recorded Investment	0	57	110	19
Interest Income Recognized	2	1	7	1
Interest Income Recognized Cash Basis	0	0	0	0
Real Estate Loans [Member] \| Construction [Member]
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	0		0		0
Recorded Investment With No Allowance	0		0		0
Recorded Investment With Allowance	0		0		0
Total Recorded Investment	0		0		0
Related Allowance	0		0		0
Average Recorded Investment	0	0	0	0
Interest Income Recognized	0	0	0	0
Interest Income Recognized Cash Basis	0	0	0	0
Consumer [Member]
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	0		0		0
Recorded Investment With No Allowance	0		0		0
Recorded Investment With Allowance	0		0		0
Total Recorded Investment	0		0		0
Related Allowance	0		0		0
Average Recorded Investment	0	0	0	0
Interest Income Recognized	0	0	0	0
Interest Income Recognized Cash Basis	0	0	0	0
Other Commercial Loans [Member]
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	5,591		5,591		5,535
Recorded Investment With No Allowance	4,494		4,494		4,653
Recorded Investment With Allowance	934		934		987
Total Recorded Investment	5,428		5,428		5,640
Related Allowance	397		397		256
Average Recorded Investment	5,298	2,107	5,743	2,488
Interest Income Recognized	53	15	187	64
Interest Income Recognized Cash Basis	2	1	5	4
Other Agricultural Loans [Member]
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	0		0		105
Recorded Investment With No Allowance	0		0		105
Recorded Investment With Allowance	0		0		0
Total Recorded Investment	0		0		105
Related Allowance	0		0		0
Average Recorded Investment	0	38	70	13
Interest Income Recognized	0	1	3	1
Interest Income Recognized Cash Basis	0	0	0	0
State and Political Subdivision Loans [Member]
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	0		0		0
Recorded Investment With No Allowance	0		0		0
Recorded Investment With Allowance	0		0		0
Total Recorded Investment	0		0		0
Related Allowance	0		0		$ 0
Average Recorded Investment	0	0	0	0
Interest Income Recognized	0	0	0	0
Interest Income Recognized Cash Basis	$ 0	$ 0	$ 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=66008989&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=66008989&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.

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 14A
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-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953550-111524

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Amount of allowance for credit losses related to recorded investment.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Recorded Investment
-URI http://asc.fasb.org/extlink&oid=65880944

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
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-Section 50
-Paragraph 15
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-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5212-111524

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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.

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

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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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