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Allowance for Probable Loan Losses (Additional Information) (Details) - USD ($) $ in Thousands | Dec. 31, 2015 | Dec. 31, 2014
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Loan loss allowances, impaired financing receivable, evaluated individually or collectively |  |
Loans Individually Evaluated for Impairment, Recorded Investment | $ 60,448 | $ 76,171
Loans Individually Evaluated for Impairment, Allowance | 2,206 | 12,221
Loans Collectively Evaluated for Impairment, Recorded Investment | 5,890,466 | 5,603,074
Loans Collectively Evaluated for Impairment, Allowance | 64,782 | 52,607
Commercial |  |
Loan loss allowances, impaired financing receivable, evaluated individually or collectively |  |
Loans Individually Evaluated for Impairment, Recorded Investment | 30,946 | 40,175
Loans Individually Evaluated for Impairment, Allowance | 1,704 | 9,112
Loans Collectively Evaluated for Impairment, Recorded Investment | 935,905 | 1,049,311
Loans Collectively Evaluated for Impairment, Allowance | 19,727 | 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 | 6,221 | 10,876
Loans Individually Evaluated for Impairment, Allowance | 100 | 1,890
Loans Collectively Evaluated for Impairment, Recorded Investment | 1,643,606 | 1,404,101
Loans Collectively Evaluated for Impairment, Allowance | 13,820 | 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 | 13,806 | 14,166
Loans Individually Evaluated for Impairment, Allowance | 202 | 1,219
Loans Collectively Evaluated for Impairment, Recorded Investment | 1,981,643 | 1,887,233
Loans Collectively Evaluated for Impairment, Allowance | 19,567 | 17,464
Commercial real estate: multifamily |  |
Loan loss allowances, impaired financing receivable, evaluated individually or collectively |  |
Loans Individually Evaluated for Impairment, Recorded Investment | 777 | 835
Loans Individually Evaluated for Impairment, Allowance | 200 |
Loans Collectively Evaluated for Impairment, Recorded Investment | 138,671 | 115,864
Loans Collectively Evaluated for Impairment, Allowance | 1,048 | 846
Residential: first lien |  |
Loan loss allowances, impaired financing receivable, evaluated individually or collectively |  |
Loans Individually Evaluated for Impairment, Recorded Investment | 5,699 | 5,840
Loans Collectively Evaluated for Impairment, Recorded Investment | 404,545 | 416,186
Loans Collectively Evaluated for Impairment, Allowance | 3,509 | 3,589
Residential: junior lien |  |
Loan loss allowances, impaired financing receivable, evaluated individually or collectively |  |
Loans Individually Evaluated for Impairment, Recorded Investment | 950 | 2,895
Loans Collectively Evaluated for Impairment, Recorded Investment | 551,388 | 485,405
Loans Collectively Evaluated for Impairment, Allowance | 5,321 | 4,683
Consumer |  |
Loan loss allowances, impaired financing receivable, evaluated individually or collectively |  |
Loans Individually Evaluated for Impairment, Recorded Investment | 1,297 | 1,384
Loans Collectively Evaluated for Impairment, Recorded Investment | 56,447 | 59,753
Loans Collectively Evaluated for Impairment, Allowance | 638 | 660
Foreign |  |
Loan loss allowances, impaired financing receivable, evaluated individually or collectively |  |
Loans Individually Evaluated for Impairment, Recorded Investment | 752 |
Loans Collectively Evaluated for Impairment, Recorded Investment | 178,261 | 185,221
Loans Collectively Evaluated for Impairment, Allowance | $ 1,152 | $ 1,060

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- 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) -URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953423-111524 + Details
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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) -URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953423-111524 + Details
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