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Allowance for Probable Loan Losses (Details 2) (USD $) In Thousands, unless otherwise specified | Dec. 31, 2011 | Dec. 31, 2010
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Loan loss allowances, impaired financing receivable, evaluated individually or collectively |  |
Loans individually evaluated for impairment, Recorded Investment | $ 136,305 | $ 125,200
Loans individually evaluated for impairment, Allowance | 27,252 | 12,171
Loans collectively evaluated for impairment, Recorded Investment | 4,917,170 | 5,284,803
Loans collectively evaluated for impairment, Allowance | 56,940 | 72,311
Commercial |  |
Loan loss allowances, impaired financing receivable, evaluated individually or collectively |  |
Loans individually evaluated for impairment, Recorded Investment | 27,603 | 23,426
Loans individually evaluated for impairment, Allowance | 14,402 | 8,138
Loans collectively evaluated for impairment, Recorded Investment | 746,213 | 807,098
Loans collectively evaluated for impairment, Allowance | 12,215 | 13,908
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 | 60,428 | 77,207
Loans individually evaluated for impairment, Allowance | 3,073 | 592
Loans collectively evaluated for impairment, Recorded Investment | 1,212,961 | 1,396,264
Loans collectively evaluated for impairment, Allowance | 16,867 | 26,103
Commercial real estate: farmland and commercial |  |
Loan loss allowances, impaired financing receivable, evaluated individually or collectively |  |
Loans individually evaluated for impairment, Recorded Investment | 42,231 | 21,844
Loans individually evaluated for impairment, Allowance | 9,754 | 3,441
Loans collectively evaluated for impairment, Recorded Investment | 1,622,456 | 1,666,719
Loans collectively evaluated for impairment, Allowance | 14,473 | 12,899
Commercial real estate: multifamily |  |
Loan loss allowances, impaired financing receivable, evaluated individually or collectively |  |
Loans individually evaluated for impairment, Recorded Investment | 411 | 473
Loans collectively evaluated for impairment, Recorded Investment | 121,188 | 96,318
Loans collectively evaluated for impairment, Allowance | 1,003 | 53
Residential: first lien |  |
Loan loss allowances, impaired financing receivable, evaluated individually or collectively |  |
Loans individually evaluated for impairment, Recorded Investment | 2,290 | 2,015
Loans individually evaluated for impairment, Allowance | 23 |
Loans collectively evaluated for impairment, Recorded Investment | 493,432 | 531,440
Loans collectively evaluated for impairment, Allowance | 4,539 | 10,059
Residential: junior lien |  |
Loan loss allowances, impaired financing receivable, evaluated individually or collectively |  |
Loans individually evaluated for impairment, Recorded Investment | 1,962 | 199
Loans collectively evaluated for impairment, Recorded Investment | 398,186 | 415,328
Loans collectively evaluated for impairment, Allowance | 4,760 | 2,611
Consumer |  |
Loan loss allowances, impaired financing receivable, evaluated individually or collectively |  |
Loans individually evaluated for impairment, Recorded Investment | 1,334 | 29
Loans collectively evaluated for impairment, Recorded Investment | 92,775 | 126,018
Loans collectively evaluated for impairment, Allowance | 1,724 | 6,241
Foreign |  |
Loan loss allowances, impaired financing receivable, evaluated individually or collectively |  |
Loans individually evaluated for impairment, Recorded Investment | 46 | 7
Loans collectively evaluated for impairment, Recorded Investment | 229,959 | 245,618
Loans collectively evaluated for impairment, Allowance | $ 1,359 | $ 437

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- Definition The valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment. + References No definition available. + Details
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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 -URI http://asc.fasb.org/extlink&oid=6965416&loc=SL6953423-111524 -Subparagraph (g) + Details
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- Definition The balance of financing receivables 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 -URI http://asc.fasb.org/extlink&oid=6965416&loc=SL6953423-111524 -Subparagraph (h) + Details
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- Definition The balance of financing receivables 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 -URI http://asc.fasb.org/extlink&oid=6965416&loc=SL6953423-111524 -Subparagraph (h) + Details
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