Loans, Impaired Loans (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Impaired loans [Abstract]
Unpaid Contractual Principal Balance	$ 12,030	$ 20,678
Recorded Investment with no Allowance	5,361	12,031
Recorded Investment with Allowance	5,343	6,726
Total Recorded Investment	10,704	18,757
Related Allowance	860	1,125
Interest income on impaired loans recognized using a cash-basis method of accounting [Abstract]
Average Recorded Investment	13,797	15,135	15,295
Interest Income Recognized	635	340	389
Commercial [Member]
Impaired loans [Abstract]
Unpaid Contractual Principal Balance	2,803	5,794
Recorded Investment with no Allowance	2,147	5,010
Recorded Investment with Allowance	531	656
Total Recorded Investment	2,678	5,666
Related Allowance	39	83
Interest income on impaired loans recognized using a cash-basis method of accounting [Abstract]
Average Recorded Investment	3,292	3,937	3,639
Interest Income Recognized	53	38	44
Commercial Real Estate [Member]
Impaired loans [Abstract]
Unpaid Contractual Principal Balance	990	3,746
Recorded Investment with no Allowance	672	2,607
Recorded Investment with Allowance	304	1,122
Total Recorded Investment	976	3,729
Related Allowance	45	63
Interest income on impaired loans recognized using a cash-basis method of accounting [Abstract]
Average Recorded Investment	2,632	3,351	4,438
Interest Income Recognized	291	85	113
Agriculture [Member]
Impaired loans [Abstract]
Unpaid Contractual Principal Balance	0	1,878
Recorded Investment with no Allowance	0	1,591
Recorded Investment with Allowance	0	0
Total Recorded Investment	0	1,591
Related Allowance	0	0
Interest income on impaired loans recognized using a cash-basis method of accounting [Abstract]
Average Recorded Investment	257	398	737
Interest Income Recognized	75	0	35
Residential Mortgage [Member]
Impaired loans [Abstract]
Unpaid Contractual Principal Balance	5,666	6,524
Recorded Investment with no Allowance	1,691	2,166
Recorded Investment with Allowance	2,956	3,409
Total Recorded Investment	4,647	5,575
Related Allowance	646	701
Interest income on impaired loans recognized using a cash-basis method of accounting [Abstract]
Average Recorded Investment	5,157	5,455	4,312
Interest Income Recognized	124	136	107
Residential Construction [Member]
Impaired loans [Abstract]
Unpaid Contractual Principal Balance	1,065	1,115
Recorded Investment with no Allowance	71	94
Recorded Investment with Allowance	826	849
Total Recorded Investment	897	943
Related Allowance	107	254
Interest income on impaired loans recognized using a cash-basis method of accounting [Abstract]
Average Recorded Investment	914	989	1,166
Interest Income Recognized	38	42	52
Consumer [Member]
Impaired loans [Abstract]
Unpaid Contractual Principal Balance	1,506	1,621
Recorded Investment with no Allowance	780	563
Recorded Investment with Allowance	726	690
Total Recorded Investment	1,506	1,253
Related Allowance	23	24
Interest income on impaired loans recognized using a cash-basis method of accounting [Abstract]
Average Recorded Investment	1,545	1,005	1,003
Interest Income Recognized	$ 54	$ 39	$ 38

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

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=35738203&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=35738203&loc=d3e5258-111524

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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

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953550-111524

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