Loans, Impaired Financing Receivable (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015	Dec. 31, 2015
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	$ 15,435		$ 15,435		$ 14,803
Recorded Investment With No Allowance	10,874		10,874		10,882
Recorded Investment With Allowance	1,730		1,730		1,402
Total Recorded Investment	12,604		12,604		12,284
Related Allowance	587		587		355
Average Recorded Investment	12,879	$ 8,691	12,838	$ 8,878
Interest Income Recognized	105	46	205	87
Interest Income Recognized Cash Basis	2	7	3	8
Real Estate Loans [Member] \| Mortgages [Member]
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	502		502		281
Recorded Investment With No Allowance	114		114		114
Recorded Investment With Allowance	345		345		129
Total Recorded Investment	459		459		243
Related Allowance	35		35		26
Average Recorded Investment	460	259	425	224
Interest Income Recognized	5	2	9	4
Interest Income Recognized Cash Basis	0	5	0	5
Real Estate Loans [Member] \| Home Equity [Member]
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	59		59		61
Recorded Investment With No Allowance	0		0		0
Recorded Investment With Allowance	59		59		61
Total Recorded Investment	59		59		61
Related Allowance	11		11		11
Average Recorded Investment	59	103	60	114
Interest Income Recognized	1	1	2	2
Interest Income Recognized Cash Basis	0	0	0	0
Real Estate Loans [Member] \| Commercial [Member]
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	8,888		8,888		8,654
Recorded Investment With No Allowance	5,944		5,944		5,843
Recorded Investment With Allowance	295		295		225
Total Recorded Investment	6,239		6,239		6,068
Related Allowance	126		126		62
Average Recorded Investment	6,158	5,700	6,142	5,862
Interest Income Recognized	26	19	52	32
Interest Income Recognized Cash Basis	0	0	0	0
Real Estate Loans [Member] \| Agricultural [Member]
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	165		165		167
Recorded Investment With No Allowance	165		165		167
Recorded Investment With Allowance	0		0		0
Total Recorded Investment	165		165		167
Related Allowance	0		0		0
Average Recorded Investment	165	0	165	0
Interest Income Recognized	3	0	5	0
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	5,717		5,717		5,535
Recorded Investment With No Allowance	4,547		4,547		4,653
Recorded Investment With Allowance	1,031		1,031		987
Total Recorded Investment	5,578		5,578		5,640
Related Allowance	415		415		256
Average Recorded Investment	5,933	2,629	5,942	2,678
Interest Income Recognized	68	24	134	49
Interest Income Recognized Cash Basis	2	2	3	3
Other Agricultural Loans [Member]
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	104		104		105
Recorded Investment With No Allowance	104		104		105
Recorded Investment With Allowance	0		0		0
Total Recorded Investment	104		104		105
Related Allowance	0		0		0
Average Recorded Investment	104	0	104	0
Interest Income Recognized	2	0	3	0
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
-SubTopic 10
-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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