Allowance for Credit Losses, Impaired Loans (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	9 Months Ended	12 Months Ended
Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Dec. 31, 2012
With no related allowance recorded [Abstract]
Recorded Investment	$ 2,135	$ 6,349	$ 2,135	$ 6,349	$ 9,214
Unpaid Principal Balance	2,572	6,451	2,572	6,451	9,435
Average Recorded Investment	5,473	4,826	7,090	4,183	5,653
Interest Income Recognized	11	19	28	51	71
With an allowance recorded [Abstract]
Recorded Investment	3,114	982	3,114	982	2,405
Unpaid Principal Balance	3,175	2,033	3,175	2,033	2,463
Related Allowance	2,213	962	2,213	962	1,374
Average Recorded Investment	3,167	1,012	3,628	1,655	1,423
Interest Income Recognized	11	3	33	5	9
Recorded Investment, Total	5,249	7,331	5,249	7,331	11,619
Unpaid Principal Balance, Total	5,747	8,484	5,747	8,484	11,898
Related Allowance	2,213	962	2,213	962	1,374
Average Recorded Investment, Total	8,640	5,838	10,718	5,838	7,076
Interest Income Recognized, Total	22	22	61	56	80
Commercial Real Estate [Member]
With no related allowance recorded [Abstract]
Recorded Investment	279	295	279	295	289
Unpaid Principal Balance	299	295	299	295	289
Average Recorded Investment	1,626	297	953	789	506
Interest Income Recognized	2	6	6	15	20
With an allowance recorded [Abstract]
Recorded Investment	0	0	0	0
Unpaid Principal Balance	0	0	0	0
Related Allowance	0	0	0	0
Average Recorded Investment	4	0	2	503
Interest Income Recognized	0	0	0	0
Related Allowance	0	0	0	0
Agricultural Real Estate [Member]
With no related allowance recorded [Abstract]
Recorded Investment	850	2,558	850	2,558	5,437
Unpaid Principal Balance	1,173	2,551	1,173	2,551	5,454
Average Recorded Investment	2,616	2,036	3,777	1,402	2,611
Interest Income Recognized	0	0	0	0	0
With an allowance recorded [Abstract]
Recorded Investment	0		0
Unpaid Principal Balance	0		0
Related Allowance	0		0
Average Recorded Investment	725		1,221
Interest Income Recognized	0		0
Related Allowance	0		0
Residential 1st Mortgages [Member]
With no related allowance recorded [Abstract]
Recorded Investment	535	494	535	494	658
Unpaid Principal Balance	588	521	588	521	761
Average Recorded Investment	533	438	643	512	458
Interest Income Recognized	4	0	11	0	3
With an allowance recorded [Abstract]
Recorded Investment	246	0	246	0	0
Unpaid Principal Balance	246	0	246	0	0
Related Allowance	50	0	50	0	0
Average Recorded Investment	123	54	27	72	54
Interest Income Recognized	0	0	0	0	0
Related Allowance	50	0	50	0	0
Home Equity Lines & Loans [Member]
With no related allowance recorded [Abstract]
Recorded Investment	287	785	287	785	792
Unpaid Principal Balance	306	862	306	862	871
Average Recorded Investment	331	743	379	717	775
Interest Income Recognized	3	6	5	17	23
With an allowance recorded [Abstract]
Recorded Investment	243	269	243	269	194
Unpaid Principal Balance	290	314	290	314	237
Related Allowance	132	248	132	248	173
Average Recorded Investment	243	174	195	152	182
Interest Income Recognized	0	1	0	3	4
Related Allowance	132	248	132	248	173
Agricultural [Member]
With no related allowance recorded [Abstract]
Recorded Investment	99	2,106	99	2,106	1,932
Unpaid Principal Balance	121	2,111	121	2,111	1,954
Average Recorded Investment	278	1,197	1,239	594	1,159
Interest Income Recognized	0	5	0	15	19
With an allowance recorded [Abstract]
Recorded Investment	488	547	488	547	2,006
Unpaid Principal Balance	488	1,551	488	1,551	2,019
Related Allowance	122	548	122	548	996
Average Recorded Investment	766	567	1,562	749	997
Interest Income Recognized	8	0	24	0	1
Related Allowance	122	548	122	548	996
Commercial [Member]
With no related allowance recorded [Abstract]
Recorded Investment	85	111	85	111	106
Unpaid Principal Balance	85	111	85	111	106
Average Recorded Investment	89	115	99	169	144
Interest Income Recognized	2	2	6	4	6
With an allowance recorded [Abstract]
Recorded Investment	2,084	146	2,084	146	144
Unpaid Principal Balance	2,095	146	2,095	146	144
Related Allowance	1,856	146	1,856	146	144
Average Recorded Investment	1,251	196	436	157	159
Interest Income Recognized	2	2	6	2	4
Related Allowance	1,856	146	1,856	146	144
Consumer & Other [Member]
With an allowance recorded [Abstract]
Recorded Investment	53	20	53	20	61
Unpaid Principal Balance	56	22	56	22	63
Related Allowance	53	20	53	20	61
Average Recorded Investment	55	21	185	22	31
Interest Income Recognized	1	0	3	0	0
Related Allowance	$ 53	$ 20	$ 53	$ 20	$ 61

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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=28368275&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=28368275&loc=d3e5258-111524

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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

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=28368275&loc=SL6953550-111524

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