Loans, Impaired Financing Receivable (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	12 Months Ended
Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Unpaid Contractual Principal Balance [Abstract]
Unpaid Contractual Principal Balance With No Related Allowance Recorded	$ 35,699	$ 37,232	$ 38,060
Unpaid Contractual Principal Balance With An Allowance Recorded	7,366	16,054	8,908
Unpaid Contractual Principal Balance, Total	43,065	53,286	46,968
Impaired Balance [Abstract]
Impaired Balance With No Related Allowance Recorded	28,083	32,134	29,491
Impaired Balance With An Allowance Recorded	7,188	13,237	8,829
Impaired Balance, Total	35,271	45,371	38,320
Related Allowance [Abstract]
Related Allowance With An Allowance Recorded	735	2,900	1,051
Related Allowance Total	735	2,900	1,051
Average Recorded Investment [Abstract]
Average Recorded Investment With No Related Allowance Recorded	28,083	32,134	29,505
Average Recorded Investment With An Allowance Recorded	7,188	13,237	10,722
Average Recorded Investment, Total	35,271	45,371	40,227
Interest Income Recognized [Abstract]
Interest Income Recognized With No Related Allowance Recorded	194	184	802
Interest Income Recognized With An Allowance Recorded	63	57	158
Interest Income Recognized, Total	257	241	960
Interest Income Collected [Abstract]
Interest Income Collected With No Related Allowance Recorded	241	207	859
Interest Income Collected With An Allowance Recorded	56	61	150
Interest Income Collected, Total	297	268	1,009
Commercial [Member]
Unpaid Contractual Principal Balance [Abstract]
Unpaid Contractual Principal Balance With No Related Allowance Recorded	492	599	310
Unpaid Contractual Principal Balance With An Allowance Recorded	94	1,380	97
Unpaid Contractual Principal Balance, Total	586	1,979	407
Impaired Balance [Abstract]
Impaired Balance With No Related Allowance Recorded	464	599	308
Impaired Balance With An Allowance Recorded	94	1,380	97
Impaired Balance, Total	558	1,979	405
Related Allowance [Abstract]
Related Allowance With An Allowance Recorded	94	423	97
Related Allowance Total	94	423	97
Average Recorded Investment [Abstract]
Average Recorded Investment With No Related Allowance Recorded	464	599	679
Average Recorded Investment With An Allowance Recorded	94	1,380	420
Average Recorded Investment, Total	558	1,979	1,099
Interest Income Recognized [Abstract]
Interest Income Recognized With No Related Allowance Recorded	(7)	5	9
Interest Income Recognized With An Allowance Recorded	0	0	0
Interest Income Recognized, Total	(7)	5	9
Interest Income Collected [Abstract]
Interest Income Collected With No Related Allowance Recorded	5	13	18
Interest Income Collected With An Allowance Recorded	0	0	0
Interest Income Collected, Total	5	13	18
Agricultural [Member]
Unpaid Contractual Principal Balance [Abstract]
Unpaid Contractual Principal Balance With No Related Allowance Recorded	174	56	50
Unpaid Contractual Principal Balance With An Allowance Recorded	0	0	0
Unpaid Contractual Principal Balance, Total	174	56	50
Impaired Balance [Abstract]
Impaired Balance With No Related Allowance Recorded	156	51	45
Impaired Balance With An Allowance Recorded	0	0	0
Impaired Balance, Total	156	51	45
Related Allowance [Abstract]
Related Allowance With An Allowance Recorded	0	0	0
Related Allowance Total	0	0	0
Average Recorded Investment [Abstract]
Average Recorded Investment With No Related Allowance Recorded	156	51	51
Average Recorded Investment With An Allowance Recorded	0	0	0
Average Recorded Investment, Total	156	51	51
Interest Income Recognized [Abstract]
Interest Income Recognized With No Related Allowance Recorded	(10)	(9)	(6)
Interest Income Recognized With An Allowance Recorded	0	0	0
Interest Income Recognized, Total	(10)	(9)	(6)
Interest Income Collected [Abstract]
Interest Income Collected With No Related Allowance Recorded	10	0	3
Interest Income Collected With An Allowance Recorded	0	0	0
Interest Income Collected, Total	10	0	3
Commercial Construction [Member]
Unpaid Contractual Principal Balance [Abstract]
Unpaid Contractual Principal Balance With No Related Allowance Recorded	9,537	7,460	9,573
Unpaid Contractual Principal Balance With An Allowance Recorded	206	5,922	207
Unpaid Contractual Principal Balance, Total	9,743	13,382	9,780
Impaired Balance [Abstract]
Impaired Balance With No Related Allowance Recorded	3,428	4,354	3,464
Impaired Balance With An Allowance Recorded	134	3,470	136
Impaired Balance, Total	3,562	7,824	3,600
Related Allowance [Abstract]
Related Allowance With An Allowance Recorded	49	1,548	54
Related Allowance Total	49	1,548	54
Average Recorded Investment [Abstract]
Average Recorded Investment With No Related Allowance Recorded	3,428	4,354	3,376
Average Recorded Investment With An Allowance Recorded	134	3,470	1,529
Average Recorded Investment, Total	3,562	7,824	4,905
Interest Income Recognized [Abstract]
Interest Income Recognized With No Related Allowance Recorded	6	8	13
Interest Income Recognized With An Allowance Recorded	0	0	0
Interest Income Recognized, Total	6	8	13
Interest Income Collected [Abstract]
Interest Income Collected With No Related Allowance Recorded	7	8	13
Interest Income Collected With An Allowance Recorded	0	0	0
Interest Income Collected, Total	7	8	13
Residential Construction [Member]
Unpaid Contractual Principal Balance [Abstract]
Unpaid Contractual Principal Balance With No Related Allowance Recorded	0	0
Unpaid Contractual Principal Balance With An Allowance Recorded	0	0
Unpaid Contractual Principal Balance, Total	0	0
Impaired Balance [Abstract]
Impaired Balance With No Related Allowance Recorded	0	0
Impaired Balance With An Allowance Recorded	0	0
Impaired Balance, Total	0	0
Related Allowance [Abstract]
Related Allowance With An Allowance Recorded	0	0
Related Allowance Total	0	0
Average Recorded Investment [Abstract]
Average Recorded Investment With No Related Allowance Recorded	0	0
Average Recorded Investment With An Allowance Recorded	0	0
Average Recorded Investment, Total	0	0
Interest Income Recognized [Abstract]
Interest Income Recognized With No Related Allowance Recorded	0	0
Interest Income Recognized With An Allowance Recorded	0	0
Interest Income Recognized, Total	0	0
Interest Income Collected [Abstract]
Interest Income Collected With No Related Allowance Recorded	0	0
Interest Income Collected With An Allowance Recorded	0	0
Interest Income Collected, Total	0	0
Commercial Real Estate [Member]
Unpaid Contractual Principal Balance [Abstract]
Unpaid Contractual Principal Balance With No Related Allowance Recorded	17,531	21,196	17,130
Unpaid Contractual Principal Balance With An Allowance Recorded	5,463	6,466	6,135
Unpaid Contractual Principal Balance, Total	22,994	27,662	23,265
Impaired Balance [Abstract]
Impaired Balance With No Related Allowance Recorded	17,037	20,686	16,228
Impaired Balance With An Allowance Recorded	5,463	6,109	6,135
Impaired Balance, Total	22,500	26,795	22,363
Related Allowance [Abstract]
Related Allowance With An Allowance Recorded	209	407	457
Related Allowance Total	209	407	457
Average Recorded Investment [Abstract]
Average Recorded Investment With No Related Allowance Recorded	17,037	20,686	18,350
Average Recorded Investment With An Allowance Recorded	5,463	6,109	6,415
Average Recorded Investment, Total	22,500	26,795	24,765
Interest Income Recognized [Abstract]
Interest Income Recognized With No Related Allowance Recorded	157	130	462
Interest Income Recognized With An Allowance Recorded	45	46	61
Interest Income Recognized, Total	202	176	523
Interest Income Collected [Abstract]
Interest Income Collected With No Related Allowance Recorded	163	132	474
Interest Income Collected With An Allowance Recorded	45	46	51
Interest Income Collected, Total	208	178	525
Residential Real Estate [Member]
Unpaid Contractual Principal Balance [Abstract]
Unpaid Contractual Principal Balance With No Related Allowance Recorded	6,141	7,113	9,137
Unpaid Contractual Principal Balance With An Allowance Recorded	1,209	962	2,073
Unpaid Contractual Principal Balance, Total	7,350	8,075	11,210
Impaired Balance [Abstract]
Impaired Balance With No Related Allowance Recorded	5,195	5,642	7,600
Impaired Balance With An Allowance Recorded	1,103	954	2,065
Impaired Balance, Total	6,298	6,596	9,665
Related Allowance [Abstract]
Related Allowance With An Allowance Recorded	330	289	414
Related Allowance Total	330	289	414
Average Recorded Investment [Abstract]
Average Recorded Investment With No Related Allowance Recorded	5,195	5,642	5,691
Average Recorded Investment With An Allowance Recorded	1,103	954	1,829
Average Recorded Investment, Total	6,298	6,596	7,520
Interest Income Recognized [Abstract]
Interest Income Recognized With No Related Allowance Recorded	42	46	312
Interest Income Recognized With An Allowance Recorded	13	11	84
Interest Income Recognized, Total	55	57	396
Interest Income Collected [Abstract]
Interest Income Collected With No Related Allowance Recorded	47	46	306
Interest Income Collected With An Allowance Recorded	6	15	87
Interest Income Collected, Total	53	61	393
Farmland [Member]
Unpaid Contractual Principal Balance [Abstract]
Unpaid Contractual Principal Balance With No Related Allowance Recorded	1,419	349	1,451
Unpaid Contractual Principal Balance With An Allowance Recorded	394	1,324	396
Unpaid Contractual Principal Balance, Total	1,813	1,673	1,847
Impaired Balance [Abstract]
Impaired Balance With No Related Allowance Recorded	1,417	348	1,449
Impaired Balance With An Allowance Recorded	394	1,324	396
Impaired Balance, Total	1,811	1,672	1,845
Related Allowance [Abstract]
Related Allowance With An Allowance Recorded	53	233	29
Related Allowance Total	53	233	29
Average Recorded Investment [Abstract]
Average Recorded Investment With No Related Allowance Recorded	1,417	348	949
Average Recorded Investment With An Allowance Recorded	394	1,324	529
Average Recorded Investment, Total	1,811	1,672	1,478
Interest Income Recognized [Abstract]
Interest Income Recognized With No Related Allowance Recorded	3	(2)	(8)
Interest Income Recognized With An Allowance Recorded	5	0	13
Interest Income Recognized, Total	8	(2)	5
Interest Income Collected [Abstract]
Interest Income Collected With No Related Allowance Recorded	3	1	18
Interest Income Collected With An Allowance Recorded	5	0	12
Interest Income Collected, Total	8	1	30
Consumer [Member]
Unpaid Contractual Principal Balance [Abstract]
Unpaid Contractual Principal Balance With No Related Allowance Recorded	200	256	202
Unpaid Contractual Principal Balance With An Allowance Recorded	0	0	0
Unpaid Contractual Principal Balance, Total	200	256	202
Impaired Balance [Abstract]
Impaired Balance With No Related Allowance Recorded	192	251	202
Impaired Balance With An Allowance Recorded	0	0	0
Impaired Balance, Total	192	251	202
Related Allowance [Abstract]
Related Allowance With An Allowance Recorded	0	0	0
Related Allowance Total	0	0	0
Average Recorded Investment [Abstract]
Average Recorded Investment With No Related Allowance Recorded	192	251	212
Average Recorded Investment With An Allowance Recorded	0	0	0
Average Recorded Investment, Total	192	251	212
Interest Income Recognized [Abstract]
Interest Income Recognized With No Related Allowance Recorded	1	4	14
Interest Income Recognized With An Allowance Recorded	0	0	0
Interest Income Recognized, Total	1	4	14
Interest Income Collected [Abstract]
Interest Income Collected With No Related Allowance Recorded	4	5	16
Interest Income Collected With An Allowance Recorded	0	0	0
Interest Income Collected, Total	4	5	16
Other [Member]
Unpaid Contractual Principal Balance [Abstract]
Unpaid Contractual Principal Balance With No Related Allowance Recorded	205	203	207
Unpaid Contractual Principal Balance With An Allowance Recorded	0	0	0
Unpaid Contractual Principal Balance, Total	205	203	207
Impaired Balance [Abstract]
Impaired Balance With No Related Allowance Recorded	194	203	195
Impaired Balance With An Allowance Recorded	0	0	0
Impaired Balance, Total	194	203	195
Related Allowance [Abstract]
Related Allowance With An Allowance Recorded	0	0	0
Related Allowance Total	0	0	0
Average Recorded Investment [Abstract]
Average Recorded Investment With No Related Allowance Recorded	194	203	197
Average Recorded Investment With An Allowance Recorded	0	0	0
Average Recorded Investment, Total	194	203	197
Interest Income Recognized [Abstract]
Interest Income Recognized With No Related Allowance Recorded	2	2	6
Interest Income Recognized With An Allowance Recorded	0	0	0
Interest Income Recognized, Total	2	2	6
Interest Income Collected [Abstract]
Interest Income Collected With No Related Allowance Recorded	2	2	11
Interest Income Collected With An Allowance Recorded	0	0	0
Interest Income Collected, Total	$ 2	$ 2	$ 11

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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=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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