Loans, Impaired Financing Receivable (Details) (USD $) In Thousands, unless otherwise specified	6 Months Ended		12 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Dec. 31, 2012
Unpaid Contractual Principal Balance [Abstract]
Unpaid Contractual Principal Balance With No Related Allowance Recorded	$ 21,873	$ 52,828	$ 36,332
Unpaid Contractual Principal Balance With An Allowance Recorded	31,618	28,266	28,034
Unpaid Contractual Principal Balance, Total	53,491	81,094	64,366
Impaired Balance [Abstract]
Impaired Balance With No Related Allowance Recorded	18,217	44,171	29,820
Impaired Balance With An Allowance Recorded	28,355	22,536	26,278
Impaired Balance, Total	46,572	66,707	56,098
Related Allowance [Abstract]
Related Allowance With No Related Allowance Recorded	0	0	0
Related Allowance With An Allowance Recorded	4,193	4,741	4,272
Related Allowance, Total	4,193	4,741	4,272
Average Recorded Investment [Abstract]
Average Recorded Investment With No Related Allowance Recorded	21,909	47,667	42,461
Average Recorded Investment With An Allowance Recorded	25,171	20,870	22,229
Average Recorded Investment, Total	47,080	68,537	64,690
Interest Income Recognized [Abstract]
Interest Income Recognized With No Related Allowance Recorded	195	481	627
Interest Income Recognized With An Allowance Recorded	308	103	621
Interest Income Recognized, Total	503	584	1,248
Interest Income Collected [Abstract]
Interest Income Collected With No Related Allowance Recorded	225	460	693
Interest Income Collected With An Allowance Recorded	310	103	571
Interest Income Collected, Total	535	563	1,264
Commercial [Member]
Unpaid Contractual Principal Balance [Abstract]
Unpaid Contractual Principal Balance With No Related Allowance Recorded	174	1,546	1,508
Unpaid Contractual Principal Balance With An Allowance Recorded	2,374	290	1,493
Unpaid Contractual Principal Balance, Total	2,548	1,836	3,001
Impaired Balance [Abstract]
Impaired Balance With No Related Allowance Recorded	172	1,456	1,042
Impaired Balance With An Allowance Recorded	2,374	290	1,493
Impaired Balance, Total	2,546	1,746	2,535
Related Allowance [Abstract]
Related Allowance With No Related Allowance Recorded	0	0	0
Related Allowance With An Allowance Recorded	551	300	463
Related Allowance, Total	551	300	463
Average Recorded Investment [Abstract]
Average Recorded Investment With No Related Allowance Recorded	147	1,568	1,053
Average Recorded Investment With An Allowance Recorded	1,919	300	943
Average Recorded Investment, Total	2,066	1,868	1,996
Interest Income Recognized [Abstract]
Interest Income Recognized With No Related Allowance Recorded	4	49	27
Interest Income Recognized With An Allowance Recorded	22	2	92
Interest Income Recognized, Total	26	51	119
Interest Income Collected [Abstract]
Interest Income Collected With No Related Allowance Recorded	6	40	28
Interest Income Collected With An Allowance Recorded	30	5	88
Interest Income Collected, Total	36	45	116
Agricultural [Member]
Unpaid Contractual Principal Balance [Abstract]
Unpaid Contractual Principal Balance With No Related Allowance Recorded	0	45	39
Unpaid Contractual Principal Balance With An Allowance Recorded	0	0	0
Unpaid Contractual Principal Balance, Total	0	45	39
Impaired Balance [Abstract]
Impaired Balance With No Related Allowance Recorded	0	45	39
Impaired Balance With An Allowance Recorded	0	0	0
Impaired Balance, Total	0	45	39
Related Allowance [Abstract]
Related Allowance With No Related Allowance Recorded	0	0	0
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	20	42	58
Average Recorded Investment With An Allowance Recorded	0	0	0
Average Recorded Investment, Total	20	42	58
Interest Income Recognized [Abstract]
Interest Income Recognized With No Related Allowance Recorded	0	0	0
Interest Income Recognized With An Allowance Recorded	0	0	0
Interest Income Recognized, Total	0	0	0
Interest Income Collected [Abstract]
Interest Income Collected With No Related Allowance Recorded	0	0	0
Interest Income Collected With An Allowance Recorded	0	0	0
Interest Income Collected, Total	0	0	0
Commercial Construction [Member]
Unpaid Contractual Principal Balance [Abstract]
Unpaid Contractual Principal Balance With No Related Allowance Recorded	3,969	11,998	10,625
Unpaid Contractual Principal Balance With An Allowance Recorded	11,017	17,961	8,267
Unpaid Contractual Principal Balance, Total	14,986	29,959	18,892
Impaired Balance [Abstract]
Impaired Balance With No Related Allowance Recorded	1,699	9,694	6,415
Impaired Balance With An Allowance Recorded	8,467	12,966	7,618
Impaired Balance, Total	10,166	22,660	14,033
Related Allowance [Abstract]
Related Allowance With No Related Allowance Recorded	0	0	0
Related Allowance With An Allowance Recorded	1,580	2,111	1,733
Related Allowance, Total	1,580	2,111	1,733
Average Recorded Investment [Abstract]
Average Recorded Investment With No Related Allowance Recorded	3,330	11,079	9,194
Average Recorded Investment With An Allowance Recorded	6,578	11,954	10,534
Average Recorded Investment, Total	9,908	23,033	19,728
Interest Income Recognized [Abstract]
Interest Income Recognized With No Related Allowance Recorded	12	(7)	27
Interest Income Recognized With An Allowance Recorded	6	0	0
Interest Income Recognized, Total	18	(7)	27
Interest Income Collected [Abstract]
Interest Income Collected With No Related Allowance Recorded	12	4	52
Interest Income Collected With An Allowance Recorded	9	0	0
Interest Income Collected, Total	21	4	52
Commercial Real Estate [Member]
Unpaid Contractual Principal Balance [Abstract]
Unpaid Contractual Principal Balance With No Related Allowance Recorded	10,879	33,857	16,566
Unpaid Contractual Principal Balance With An Allowance Recorded	13,436	5,163	12,759
Unpaid Contractual Principal Balance, Total	24,315	39,020	29,325
Impaired Balance [Abstract]
Impaired Balance With No Related Allowance Recorded	10,148	28,254	15,506
Impaired Balance With An Allowance Recorded	13,436	5,141	12,745
Impaired Balance, Total	23,584	33,395	28,251
Related Allowance [Abstract]
Related Allowance With No Related Allowance Recorded	0	0	0
Related Allowance With An Allowance Recorded	1,080	1,462	1,236
Related Allowance, Total	1,080	1,462	1,236
Average Recorded Investment [Abstract]
Average Recorded Investment With No Related Allowance Recorded	12,740	30,136	26,482
Average Recorded Investment With An Allowance Recorded	11,677	4,394	6,399
Average Recorded Investment, Total	24,417	34,530	32,881
Interest Income Recognized [Abstract]
Interest Income Recognized With No Related Allowance Recorded	112	358	430
Interest Income Recognized With An Allowance Recorded	240	55	384
Interest Income Recognized, Total	352	413	814
Interest Income Collected [Abstract]
Interest Income Collected With No Related Allowance Recorded	133	325	421
Interest Income Collected With An Allowance Recorded	234	53	366
Interest Income Collected, Total	367	378	787
Residential RE [Member]
Unpaid Contractual Principal Balance [Abstract]
Unpaid Contractual Principal Balance With No Related Allowance Recorded	4,327	2,748	4,450
Unpaid Contractual Principal Balance With An Allowance Recorded	4,791	4,852	5,515
Unpaid Contractual Principal Balance, Total	9,118	7,600	9,965
Impaired Balance [Abstract]
Impaired Balance With No Related Allowance Recorded	3,685	2,152	4,132
Impaired Balance With An Allowance Recorded	4,078	4,139	4,422
Impaired Balance, Total	7,763	6,291	8,554
Related Allowance [Abstract]
Related Allowance With No Related Allowance Recorded	0	0	0
Related Allowance With An Allowance Recorded	982	868	840
Related Allowance, Total	982	868	840
Average Recorded Investment [Abstract]
Average Recorded Investment With No Related Allowance Recorded	3,033	2,280	3,096
Average Recorded Investment With An Allowance Recorded	4,997	4,092	4,288
Average Recorded Investment, Total	8,030	6,372	7,384
Interest Income Recognized [Abstract]
Interest Income Recognized With No Related Allowance Recorded	62	46	89
Interest Income Recognized With An Allowance Recorded	40	46	145
Interest Income Recognized, Total	102	92	234
Interest Income Collected [Abstract]
Interest Income Collected With No Related Allowance Recorded	67	42	123
Interest Income Collected With An Allowance Recorded	37	45	117
Interest Income Collected, Total	104	87	240
Farmland [Member]
Unpaid Contractual Principal Balance [Abstract]
Unpaid Contractual Principal Balance With No Related Allowance Recorded	2,307	2,340	2,829
Unpaid Contractual Principal Balance With An Allowance Recorded	0	0	0
Unpaid Contractual Principal Balance, Total	2,307	2,340	2,829
Impaired Balance [Abstract]
Impaired Balance With No Related Allowance Recorded	2,307	2,297	2,413
Impaired Balance With An Allowance Recorded	0	0	0
Impaired Balance, Total	2,307	2,297	2,413
Related Allowance [Abstract]
Related Allowance With No Related Allowance Recorded	0	0	0
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	2,427	2,297	2,326
Average Recorded Investment With An Allowance Recorded	0	130	65
Average Recorded Investment, Total	2,427	2,427	2,391
Interest Income Recognized [Abstract]
Interest Income Recognized With No Related Allowance Recorded	1	32	43
Interest Income Recognized With An Allowance Recorded	0	0	0
Interest Income Recognized, Total	1	32	43
Interest Income Collected [Abstract]
Interest Income Collected With No Related Allowance Recorded	1	44	55
Interest Income Collected With An Allowance Recorded	0	0	0
Interest Income Collected, Total	1	44	55
Consumer [Member]
Unpaid Contractual Principal Balance [Abstract]
Unpaid Contractual Principal Balance With No Related Allowance Recorded	217	256	297
Unpaid Contractual Principal Balance With An Allowance Recorded	0	0	0
Unpaid Contractual Principal Balance, Total	217	256	297
Impaired Balance [Abstract]
Impaired Balance With No Related Allowance Recorded	206	237	255
Impaired Balance With An Allowance Recorded	0	0	0
Impaired Balance, Total	206	237	255
Related Allowance [Abstract]
Related Allowance With No Related Allowance Recorded	0	0	0
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	212	225	228
Average Recorded Investment With An Allowance Recorded	0	0	0
Average Recorded Investment, Total	212	225	228
Interest Income Recognized [Abstract]
Interest Income Recognized With No Related Allowance Recorded	4	3	10
Interest Income Recognized With An Allowance Recorded	0	0	0
Interest Income Recognized, Total	4	3	10
Interest Income Collected [Abstract]
Interest Income Collected With No Related Allowance Recorded	6	5	13
Interest Income Collected With An Allowance Recorded	0	0	0
Interest Income Collected, Total	6	5	13
Other [Member]
Unpaid Contractual Principal Balance [Abstract]
Unpaid Contractual Principal Balance With No Related Allowance Recorded	0	38	18
Unpaid Contractual Principal Balance With An Allowance Recorded	0	0	0
Unpaid Contractual Principal Balance, Total	0	38	18
Impaired Balance [Abstract]
Impaired Balance With No Related Allowance Recorded	0	36	18
Impaired Balance With An Allowance Recorded	0	0	0
Impaired Balance, Total	0	36	18
Related Allowance [Abstract]
Related Allowance With No Related Allowance Recorded	0	0	0
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	0	40	24
Average Recorded Investment With An Allowance Recorded	0	0	0
Average Recorded Investment, Total	0	40	24
Interest Income Recognized [Abstract]
Interest Income Recognized With No Related Allowance Recorded	0	0	1
Interest Income Recognized With An Allowance Recorded	0	0	0
Interest Income Recognized, Total	0	0	1
Interest Income Collected [Abstract]
Interest Income Collected With No Related Allowance Recorded	0	0	1
Interest Income Collected With An Allowance Recorded	0	0	0
Interest Income Collected, Total	0	0	1
Residential Construction [Member]
Unpaid Contractual Principal Balance [Abstract]
Unpaid Contractual Principal Balance With No Related Allowance Recorded	0	0	0
Unpaid Contractual Principal Balance With An Allowance Recorded	0	0	0
Unpaid Contractual Principal Balance, Total	0	0	0
Impaired Balance [Abstract]
Impaired Balance With No Related Allowance Recorded	0	0	0
Impaired Balance With An Allowance Recorded	0	0	0
Impaired Balance, Total	0	0	0
Related Allowance [Abstract]
Related Allowance With No Related Allowance Recorded	0	0	0
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	0	0	0
Average Recorded Investment With An Allowance Recorded	0	0	0
Average Recorded Investment, Total	0	0	0
Interest Income Recognized [Abstract]
Interest Income Recognized With No Related Allowance Recorded	0	0	0
Interest Income Recognized With An Allowance Recorded	0	0	0
Interest Income Recognized, Total	0	0	0
Interest Income Collected [Abstract]
Interest Income Collected With No Related Allowance Recorded	0	0	0
Interest Income Collected With An Allowance Recorded	0	0	0
Interest Income Collected, Total	$ 0	$ 0	$ 0