Loans Schedule of Recorded Investment in Impaired Loans (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
Impaired Financing Receivable, Unpaid Principal Balance
Unpaid Total Principal Balance	$ 114,871		$ 120,387
Recorded Investment With No Allowance	51,427		56,236
Recorded Investment With Allowance	37,217		35,729
Total Recorded Investment	88,644		91,965
Related Allowance	13,947		11,575
Impaired Financing Receivable, Average Recorded Investment and Cash Basis Method Interest Income
Average Recorded Investment	76,535	$ 84,599
Income Recognized	60	198
Interest Income on Impaired Loans If Interest Had Been Accrued	929	1,035
Commercial real estate
Impaired Financing Receivable, Unpaid Principal Balance
Unpaid Total Principal Balance	55,222		58,179
Recorded Investment With No Allowance	25,759		27,882
Recorded Investment With Allowance	18,117		17,614
Total Recorded Investment	43,876		45,496
Related Allowance	4,526		3,401
Impaired Financing Receivable, Average Recorded Investment and Cash Basis Method Interest Income
Average Recorded Investment	33,483	42,077
Income Recognized	36	150
Land acquisition & development construction real estate
Impaired Financing Receivable, Unpaid Principal Balance
Unpaid Total Principal Balance	15,252		15,503
Recorded Investment With No Allowance	7,742		7,245
Recorded Investment With Allowance	322		778
Total Recorded Investment	8,064		8,023
Related Allowance	150		282
Impaired Financing Receivable, Average Recorded Investment and Cash Basis Method Interest Income
Average Recorded Investment	7,508	8,930
Income Recognized	7	10
Residential construction real estate
Impaired Financing Receivable, Unpaid Principal Balance
Unpaid Total Principal Balance	988		992
Recorded Investment With No Allowance	282		293
Recorded Investment With Allowance	0		0
Total Recorded Investment	282		293
Related Allowance	0		0
Impaired Financing Receivable, Average Recorded Investment and Cash Basis Method Interest Income
Average Recorded Investment	288	308
Income Recognized	0	0
Commercial construction real estate
Impaired Financing Receivable, Unpaid Principal Balance
Unpaid Total Principal Balance	1,370		1,264
Recorded Investment With No Allowance	446		340
Recorded Investment With Allowance	731		739
Total Recorded Investment	1,177		1,079
Related Allowance	739		739
Impaired Financing Receivable, Average Recorded Investment and Cash Basis Method Interest Income
Average Recorded Investment	1,067	3,055
Income Recognized	0	2
Total construction loans
Impaired Financing Receivable, Unpaid Principal Balance
Unpaid Total Principal Balance	17,610		17,759
Recorded Investment With No Allowance	8,470		7,878
Recorded Investment With Allowance	1,053		1,517
Total Recorded Investment	9,523		9,395
Related Allowance	889		1,021
Impaired Financing Receivable, Average Recorded Investment and Cash Basis Method Interest Income
Average Recorded Investment	8,863	12,293
Income Recognized	7	12
Residential real estate
Impaired Financing Receivable, Unpaid Principal Balance
Unpaid Total Principal Balance	5,664		7,073
Recorded Investment With No Allowance	3,019		3,547
Recorded Investment With Allowance	1,152		2,317
Total Recorded Investment	4,171		5,864
Related Allowance	160		367
Impaired Financing Receivable, Average Recorded Investment and Cash Basis Method Interest Income
Average Recorded Investment	4,206	3,127
Income Recognized	1	1
Agricultural real estate
Impaired Financing Receivable, Unpaid Principal Balance
Unpaid Total Principal Balance	6,685		6,434
Recorded Investment With No Allowance	5,816		5,563
Recorded Investment With Allowance	201		198
Total Recorded Investment	6,017		5,761
Related Allowance	7		5
Impaired Financing Receivable, Average Recorded Investment and Cash Basis Method Interest Income
Average Recorded Investment	5,748	8,655
Income Recognized	1	22
Total real estate loans
Impaired Financing Receivable, Unpaid Principal Balance
Unpaid Total Principal Balance	85,181		89,445
Recorded Investment With No Allowance	43,064		44,870
Recorded Investment With Allowance	20,523		21,646
Total Recorded Investment	63,587		66,516
Related Allowance	5,582		4,794
Impaired Financing Receivable, Average Recorded Investment and Cash Basis Method Interest Income
Average Recorded Investment	52,300	66,152
Income Recognized	45	185
Commercial
Impaired Financing Receivable, Unpaid Principal Balance
Unpaid Total Principal Balance	28,782		29,593
Recorded Investment With No Allowance	8,113		10,744
Recorded Investment With Allowance	16,150		13,727
Total Recorded Investment	24,263		24,471
Related Allowance	8,176		6,487
Impaired Financing Receivable, Average Recorded Investment and Cash Basis Method Interest Income
Average Recorded Investment	23,379	17,533
Income Recognized	15	8
Agricultural
Impaired Financing Receivable, Unpaid Principal Balance
Unpaid Total Principal Balance	908		1,349
Recorded Investment With No Allowance	250		622
Recorded Investment With Allowance	544		356
Total Recorded Investment	794		978
Related Allowance	189		$ 294
Impaired Financing Receivable, Average Recorded Investment and Cash Basis Method Interest Income
Average Recorded Investment	856	914
Income Recognized	$ 0	$ 5

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Impaired Financing Receivable, Interest Income, Accrual Method and Cash Basis Method

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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=49124121&loc=d3e5212-111524

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=49124121&loc=d3e5258-111524

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 14A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=49124121&loc=SL6953550-111524

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