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Allowance for Probable Loan Losses (Details 4) (USD $) In Thousands, unless otherwise specified | 9 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2011 | Dec. 31, 2010
Loan loss allowances, impaired financing receivable |  |
Period of charge off for past due unsecured commercial loans (in days) | 90 |
Commercial | Loans with Related Allowance |  |
Loan loss allowances, impaired financing receivable |  |
Recorded Investment | $ 23,018 | $ 23,062
Unpaid Principal Balance | 23,061 | 23,071
Related Allowance | 8,049 | 8,138
Average Recorded Investment | 23,084 | 23,096
Interest Recognized | 30 | 42
Commercial | Loans with No Related Allowance |  |
Loan loss allowances, impaired financing receivable |  |
Recorded Investment | 655 | 364
Unpaid Principal Balance | 665 | 980
Average Recorded Investment | 662 | 993
Interest Recognized |  | 30
Commercial real estate: other construction and land development | Loans with Related Allowance |  |
Loan loss allowances, impaired financing receivable |  |
Recorded Investment | 35,250 | 10,603
Unpaid Principal Balance | 35,272 | 10,645
Related Allowance | 3,000 | 592
Average Recorded Investment | 35,248 | 10,622
Commercial real estate: other construction and land development | Loans with No Related Allowance |  |
Loan loss allowances, impaired financing receivable |  |
Recorded Investment | 26,036 | 66,604
Unpaid Principal Balance | 26,036 | 66,755
Average Recorded Investment | 27,680 | 68,608
Interest Recognized | 58 | 2
Commercial real estate: farmland and commercial | Loans with Related Allowance |  |
Loan loss allowances, impaired financing receivable |  |
Recorded Investment | 29,915 | 17,841
Unpaid Principal Balance | 29,929 | 17,878
Related Allowance | 7,923 | 3,441
Average Recorded Investment | 24,160 | 18,475
Interest Recognized | 607 | 860
Commercial real estate: farmland and commercial | Loans with No Related Allowance |  |
Loan loss allowances, impaired financing receivable |  |
Recorded Investment | 17,386 | 4,003
Unpaid Principal Balance | 17,832 | 5,606
Average Recorded Investment | 17,145 | 5,594
Interest Recognized | 48 |
Commercial real estate: multifamily | Loans with No Related Allowance |  |
Loan loss allowances, impaired financing receivable |  |
Recorded Investment | 431 | 473
Unpaid Principal Balance | 431 | 473
Average Recorded Investment | 447 | 500
Residential: first lien | Loans with Related Allowance |  |
Loan loss allowances, impaired financing receivable |  |
Recorded Investment | 389 |
Unpaid Principal Balance | 389 |
Related Allowance | 94 |
Average Recorded Investment | 389 |
Residential: first lien | Loans with No Related Allowance |  |
Loan loss allowances, impaired financing receivable |  |
Recorded Investment | 1,792 | 2,015
Unpaid Principal Balance | 1,847 | 2,143
Average Recorded Investment | 1,629 | 2,297
Interest Recognized | 14 |
Residential: junior lien | Loans with No Related Allowance |  |
Loan loss allowances, impaired financing receivable |  |
Recorded Investment | 1,722 | 199
Unpaid Principal Balance | 1,729 | 226
Average Recorded Investment | 1,708 | 228
Interest Recognized | 86 |
Consumer | Loans with No Related Allowance |  |
Loan loss allowances, impaired financing receivable |  |
Recorded Investment | 1,299 | 29
Unpaid Principal Balance | 1,301 | 46
Average Recorded Investment | 1,624 | 49
Foreign | Loans with No Related Allowance |  |
Loan loss allowances, impaired financing receivable |  |
Recorded Investment |  | 7
Unpaid Principal Balance |  | 7
Average Recorded Investment |  | 19
Loans with Related Allowance |  |
Loan loss allowances, impaired financing receivable |  |
Recorded Investment | 88,572 | 51,506
Unpaid Principal Balance | 88,651 | 51,594
Related Allowance | 19,066 | 12,171
Average Recorded Investment | 82,881 | 52,193
Interest Recognized | 637 | 902
Loans with No Related Allowance |  |
Loan loss allowances, impaired financing receivable |  |
Recorded Investment | 49,321 | 73,694
Unpaid Principal Balance | 49,841 | 76,236
Average Recorded Investment | 50,895 | 78,288
Interest Recognized | $ 206 | $ 32

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- Definition The average recorded investment related to impaired financing receivables. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 15 -URI http://asc.fasb.org/extlink&oid=6965416&loc=d3e5212-111524 -Subparagraph (c)(1) Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 17 -URI http://asc.fasb.org/extlink&oid=6965416&loc=d3e5258-111524 + Details
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