Loans - Schedule of Recorded Investment in Impaired Loans (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Impaired Financing Receivable, Unpaid Principal Balance
Unpaid Total Principal Balance	$ 87,240	$ 124,867	$ 158,512
Recorded Investment With No Allowance	57,050	62,724	82,232
Recorded Investment With Allowance	21,430	47,848	53,953
Total Recorded Investment	78,480	110,572	136,185
Related allowance	5,792	8,929	10,297
Commercial real estate
Impaired Financing Receivable, Unpaid Principal Balance
Unpaid Total Principal Balance	41,603	64,780	84,300
Recorded Investment With No Allowance	28,143	29,216	39,049
Recorded Investment With Allowance	11,246	33,937	34,774
Total Recorded Investment	39,389	63,153	73,823
Related allowance	1,608	5,210	4,112
Land acquisition & development construction real estate
Impaired Financing Receivable, Unpaid Principal Balance
Unpaid Total Principal Balance	12,511	23,906	28,558
Recorded Investment With No Allowance	7,262	9,901	15,891
Recorded Investment With Allowance	1,615	7,226	7,173
Total Recorded Investment	8,877	17,127	23,064
Related allowance	574	1,434	1,457
Residential construction real estate
Impaired Financing Receivable, Unpaid Principal Balance
Unpaid Total Principal Balance	459	1,816	3,018
Recorded Investment With No Allowance	272	1,095	1,976
Recorded Investment With Allowance	0	277	710
Total Recorded Investment	272	1,372	2,686
Related allowance	0	26	251
Commercial construction real estate
Impaired Financing Receivable, Unpaid Principal Balance
Unpaid Total Principal Balance	2,729	397	10,447
Recorded Investment With No Allowance	253	279	7,785
Recorded Investment With Allowance	2,442	84	340
Total Recorded Investment	2,695	363	8,125
Related allowance	904	85	69
Total construction loans
Impaired Financing Receivable, Unpaid Principal Balance
Unpaid Total Principal Balance	15,699	26,119	42,023
Recorded Investment With No Allowance	7,787	11,275	25,652
Recorded Investment With Allowance	4,057	7,587	8,223
Total Recorded Investment	11,844	18,862	33,875
Related allowance	1,478	1,545	1,777
Residential real estate
Impaired Financing Receivable, Unpaid Principal Balance
Unpaid Total Principal Balance	2,959	9,448	13,271
Recorded Investment With No Allowance	2,452	5,081	6,152
Recorded Investment With Allowance	341	967	4,495
Total Recorded Investment	2,793	6,048	10,647
Related allowance	143	249	1,677
Agricultural real estate
Impaired Financing Receivable, Unpaid Principal Balance
Unpaid Total Principal Balance	8,844	8,895	5,559
Recorded Investment With No Allowance	6,444	6,429	1,834
Recorded Investment With Allowance	2,305	2,370	3,227
Total Recorded Investment	8,749	8,799	5,061
Related allowance	732	335	784
Total real estate loans
Impaired Financing Receivable, Unpaid Principal Balance
Unpaid Total Principal Balance	69,105	109,242	145,153
Recorded Investment With No Allowance	44,826	52,001	72,687
Recorded Investment With Allowance	17,949	44,861	50,719
Total Recorded Investment	62,775	96,862	123,406
Related allowance	3,961	7,339	8,350
Commercial
Impaired Financing Receivable, Unpaid Principal Balance
Unpaid Total Principal Balance	16,904	15,448	12,770
Recorded Investment With No Allowance	11,882	10,684	9,036
Recorded Investment With Allowance	2,644	2,901	3,206
Total Recorded Investment	14,526	13,585	12,242
Related allowance	1,190	1,504	1,919
Agricultural
Impaired Financing Receivable, Unpaid Principal Balance
Unpaid Total Principal Balance	1,231	177	589
Recorded Investment With No Allowance	342	39	509
Recorded Investment With Allowance	837	86	28
Total Recorded Investment	1,179	125	537
Related allowance	$ 641	$ 86	$ 28

No authoritative reference available.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 14A

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