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Allowance for Probable Loan Losses (Details 2) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Loan loss allowances, impaired financing receivable, evaluated individually or collectively
Loans individually evaluated for impairment, Recorded Investment	$ 58,531	$ 76,171
Loans individually evaluated for impairment, Allowance	2,847	12,221
Loans collectively evaluated for impairment, Recorded Investment	5,715,931	5,603,074
Loans collectively evaluated for impairment, Allowance	57,691	52,607
Commercial
Loan loss allowances, impaired financing receivable, evaluated individually or collectively
Loans individually evaluated for impairment, Recorded Investment	33,198	40,175
Loans individually evaluated for impairment, Allowance	1,200	9,112
Loans collectively evaluated for impairment, Recorded Investment	997,370	1,049,311
Loans collectively evaluated for impairment, Allowance	17,702	13,240
Commercial Real Estate: Other Construction and Land Development
Loan loss allowances, impaired financing receivable, evaluated individually or collectively
Loans individually evaluated for impairment, Recorded Investment	6,688	10,876
Loans individually evaluated for impairment, Allowance	1,142	1,890
Loans collectively evaluated for impairment, Recorded Investment	1,550,192	1,404,101
Loans collectively evaluated for impairment, Allowance	12,382	11,065
Commercial real estate: farmland and commercial
Loan loss allowances, impaired financing receivable, evaluated individually or collectively
Loans individually evaluated for impairment, Recorded Investment	9,629	14,166
Loans individually evaluated for impairment, Allowance	505	1,219
Loans collectively evaluated for impairment, Recorded Investment	1,908,036	1,887,233
Loans collectively evaluated for impairment, Allowance	17,380	17,464
Commercial real estate: multifamily
Loan loss allowances, impaired financing receivable, evaluated individually or collectively
Loans individually evaluated for impairment, Recorded Investment	827	835
Loans collectively evaluated for impairment, Recorded Investment	93,176	115,864
Loans collectively evaluated for impairment, Allowance	685	846
Residential: first lien
Loan loss allowances, impaired financing receivable, evaluated individually or collectively
Loans individually evaluated for impairment, Recorded Investment	5,372	5,840
Loans collectively evaluated for impairment, Recorded Investment	409,091	416,186
Loans collectively evaluated for impairment, Allowance	3,434	3,589
Residential: junior lien
Loan loss allowances, impaired financing receivable, evaluated individually or collectively
Loans individually evaluated for impairment, Recorded Investment	1,260	2,895
Loans collectively evaluated for impairment, Recorded Investment	512,507	485,405
Loans collectively evaluated for impairment, Allowance	4,308	4,683
Consumer
Loan loss allowances, impaired financing receivable, evaluated individually or collectively
Loans individually evaluated for impairment, Recorded Investment	1,158	1,384
Loans collectively evaluated for impairment, Recorded Investment	56,808	59,753
Loans collectively evaluated for impairment, Allowance	625	660
Foreign
Loan loss allowances, impaired financing receivable, evaluated individually or collectively
Loans individually evaluated for impairment, Recorded Investment	399
Loans collectively evaluated for impairment, Recorded Investment	188,751	185,221
Loans collectively evaluated for impairment, Allowance	$ 1,175	$ 1,060

X

- Definition

The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

+ References

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



-Publisher FASB



-Name Accounting Standards Codification



-Topic 310



-SubTopic 10



-Section 50



-Paragraph 11B



-Subparagraph (g)



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- Definition

Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

+ References

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



-Publisher FASB



-Name Accounting Standards Codification



-Topic 310



-SubTopic 10



-Section 50



-Paragraph 11B



-Subparagraph (g)



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+ References

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-Publisher FASB



-Name Accounting Standards Codification



-Topic 310



-SubTopic 10



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-Paragraph 11B



-Subparagraph (h)



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-Publisher FASB



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-SubTopic 10



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-Paragraph 11B



-Subparagraph (h)



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