Allowance for Credit Losses, Impaired Loans (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended	12 Months Ended
Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012	Dec. 31, 2012
With no related allowance recorded [Abstract]
Recorded Investment	$ 8,808	$ 3,355	$ 8,808	$ 3,355	$ 9,214
Unpaid Principal Balance	9,238	3,719	9,238	3,719	9,435
Average Recorded Investment	7,633	3,524	7,736	3,863	5,653
Interest Income Recognized	9	21	17	32	71
With an allowance recorded [Abstract]
Recorded Investment	3,216	1,039	3,216	1,039	2,405
Unpaid Principal Balance	3,694	2,031	3,694	2,031	2,463
Related Allowance	1,402	915	1,402	915	1,374
Average Recorded Investment	3,845	1,153	3,643	1,979	1,423
Interest Income Recognized	11	1	22	2	9
Recorded Investment, Total	12,024	4,394	12,024	4,394	11,619
Unpaid Principal Balance, Total	12,932	5,750	12,932	5,750	11,898
Related Allowance	1,402	915	1,402	915	1,374
Average Recorded Investment, Total	11,478	4,677	11,379	5,842	7,076
Interest Income Recognized, Total	20	22	39	34	80
Commercial Real Estate [Member]
With no related allowance recorded [Abstract]
Recorded Investment	2,973	298	2,973	298	289
Unpaid Principal Balance	2,993	299	2,993	299	289
Average Recorded Investment	1,540	720	869	1,035	506
Interest Income Recognized	2	6	4	9	20
With an allowance recorded [Abstract]
Recorded Investment	7	0	7	0
Unpaid Principal Balance	6	0	6	0
Related Allowance	6	0	6	0
Average Recorded Investment	4	0	2	755
Interest Income Recognized	0	0	0	0
Related Allowance	6	0	6	0
Agricultural Real Estate [Member]
With no related allowance recorded [Abstract]
Recorded Investment	4,382	1,514	4,382	1,514	5,437
Unpaid Principal Balance	4,673	1,777	4,673	1,777	5,454
Average Recorded Investment	3,945	1,224	4,209	1,085	2,611
Interest Income Recognized	0	0	0	0	0
With an allowance recorded [Abstract]
Recorded Investment	1,449		1,449
Unpaid Principal Balance	1,843		1,843
Related Allowance	300		300
Average Recorded Investment	1,645		1,283
Interest Income Recognized	0		0
Related Allowance	300		300
Residential 1st Mortgages [Member]
With no related allowance recorded [Abstract]
Recorded Investment	530	387	530	387	658
Unpaid Principal Balance	580	416	580	416	761
Average Recorded Investment	633	340	665	549	458
Interest Income Recognized	4	0	7	0	3
With an allowance recorded [Abstract]
Recorded Investment		108		108	0
Unpaid Principal Balance		109		109	0
Related Allowance		51		51	0
Average Recorded Investment		108		81	54
Interest Income Recognized		0		0	0
Related Allowance		51		51	0
Home Equity Lines & Loans [Member]
With no related allowance recorded [Abstract]
Recorded Investment	374	750	374	750	792
Unpaid Principal Balance	397	821	397	821	871
Average Recorded Investment	312	762	417	704	775
Interest Income Recognized	1	7	2	11	23
With an allowance recorded [Abstract]
Recorded Investment	243	78	243	78	194
Unpaid Principal Balance	289	82	289	82	237
Related Allowance	243	60	243	60	173
Average Recorded Investment	198	133	186	142	182
Interest Income Recognized	0	1	0	2	4
Related Allowance	243	60	243	60	173
Agricultural [Member]
With no related allowance recorded [Abstract]
Recorded Investment	457	288	457	288	1,932
Unpaid Principal Balance	503	288	503	288	1,954
Average Recorded Investment	1,105	299	1,474	293	1,159
Interest Income Recognized	0	6	0	10	19
With an allowance recorded [Abstract]
Recorded Investment	1,043	587	1,043	587	2,006
Unpaid Principal Balance	1,068	1,566	1,068	1,566	2,019
Related Allowance	596	586	596	586	996
Average Recorded Investment	1,516	717	1,757	840	997
Interest Income Recognized	8	0	16	0	1
Related Allowance	596	586	596	586	996
Commercial [Member]
With no related allowance recorded [Abstract]
Recorded Investment	92	118	92	118	106
Unpaid Principal Balance	92	118	92	118	106
Average Recorded Investment	98	179	102	197	144
Interest Income Recognized	2	2	4	2	6
With an allowance recorded [Abstract]
Recorded Investment	418	245	418	245	144
Unpaid Principal Balance	430	252	430	252	144
Related Allowance	202	197	202	197	144
Average Recorded Investment	281	173	213	138	159
Interest Income Recognized	2	0	4	0	4
Related Allowance	202	197	202	197	144
Consumer & Other [Member]
With an allowance recorded [Abstract]
Recorded Investment	56	21	56	21	61
Unpaid Principal Balance	58	22	58	22	63
Related Allowance	55	21	55	21	61
Average Recorded Investment	201	22	202	23	31
Interest Income Recognized	1	0	2	0	0
Related Allowance	$ 55	$ 21	$ 55	$ 21	$ 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=7512638&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=7512638&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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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=7512638&loc=SL6953550-111524

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