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Allowance for Probable Loan Losses (Details 4) (USD $) In Thousands, unless otherwise specified | 3 Months Ended | 6 Months Ended | 12 Months Ended
--- | --- | --- | ---
Jun. 30, 2012 | Jun. 30, 2011 | Jun. 30, 2012 | Jun. 30, 2011 | Dec. 31, 2011
Loan loss allowances, impaired financing receivable |  |  |  |  |
Period of charge off for past due unsecured commercial loans (in days) |  |  | 90 |  |
Loans with Related Allowance |  |  |  |  |
Loan loss allowances, impaired financing receivable |  |  |  |  |
Recorded Investment | $ 36,945 |  | $ 36,945 |  | $ 87,369
Unpaid Principal Balance | 40,082 |  | 40,082 |  | 87,419
Related Allowance | 18,631 |  | 18,631 |  | 27,252
Average Recorded Investment | 64,403 | 73,545 | 71,543 | 79,390 | 87,951
Interest Recognized | 23 | 357 | 56 | 761 | 858
Loans with No Related Allowance |  |  |  |  |
Loan loss allowances, impaired financing receivable |  |  |  |  |
Recorded Investment | 41,321 |  | 41,321 |  | 48,936
Unpaid Principal Balance | 41,955 |  | 41,955 |  | 51,423
Average Recorded Investment | 51,563 | 35,727 | 53,908 | 43,663 | 54,359
Interest Recognized | 81 | 79 | 179 | 116 | 399
Commercial | Loans with Related Allowance |  |  |  |  |
Loan loss allowances, impaired financing receivable |  |  |  |  |
Recorded Investment | 24,256 |  | 24,256 |  | 24,108
Unpaid Principal Balance | 24,256 |  | 24,256 |  | 24,108
Related Allowance | 15,098 |  | 15,098 |  | 14,402
Average Recorded Investment | 24,271 | 22,944 | 24,417 | 22,948 | 24,145
Interest Recognized |  | 10 | 10 | 20 | 41
Commercial | Loans with No Related Allowance |  |  |  |  |
Loan loss allowances, impaired financing receivable |  |  |  |  |
Recorded Investment | 3,797 |  | 3,797 |  | 3,495
Unpaid Principal Balance | 3,908 |  | 3,908 |  | 3,932
Average Recorded Investment | 3,798 | 439 | 3,808 | 458 | 3,942
Interest Recognized | 1 | 4 | 1 | 9 | 20
Commercial real estate: other construction and land development | Loans with Related Allowance |  |  |  |  |
Loan loss allowances, impaired financing receivable |  |  |  |  |
Recorded Investment | 3,671 |  | 3,671 |  | 34,417
Unpaid Principal Balance | 3,671 |  | 3,671 |  | 34,432
Related Allowance | 568 |  | 568 |  | 3,073
Average Recorded Investment | 27,377 | 27,815 | 33,384 | 32,873 | 34,709
Interest Recognized |  | 140 |  | 328 |
Commercial real estate: other construction and land development | Loans with No Related Allowance |  |  |  |  |
Loan loss allowances, impaired financing receivable |  |  |  |  |
Recorded Investment | 22,045 |  | 22,045 |  | 26,011
Unpaid Principal Balance | 22,110 |  | 22,110 |  | 26,112
Average Recorded Investment | 29,816 | 24,637 | 31,627 | 28,473 | 27,722
Interest Recognized | 41 | 24 | 99 | 56 | 128
Commercial real estate: farmland and commercial | Loans with Related Allowance |  |  |  |  |
Loan loss allowances, impaired financing receivable |  |  |  |  |
Recorded Investment | 8,817 |  | 8,817 |  | 28,636
Unpaid Principal Balance | 11,954 |  | 11,954 |  | 28,671
Related Allowance | 2,942 |  | 2,942 |  | 9,754
Average Recorded Investment | 12,553 | 22,267 | 13,539 | 22,231 | 28,883
Interest Recognized | 23 | 207 | 46 | 413 | 817
Commercial real estate: farmland and commercial | Loans with No Related Allowance |  |  |  |  |
Loan loss allowances, impaired financing receivable |  |  |  |  |
Recorded Investment | 9,511 |  | 9,511 |  | 13,595
Unpaid Principal Balance | 9,854 |  | 9,854 |  | 15,394
Average Recorded Investment | 11,545 | 5,501 | 11,996 | 4,783 | 16,271
Interest Recognized |  |  | 8 |  | 102
Commercial real estate: multifamily | Loans with No Related Allowance |  |  |  |  |
Loan loss allowances, impaired financing receivable |  |  |  |  |
Recorded Investment | 382 |  | 382 |  | 411
Unpaid Principal Balance | 382 |  | 382 |  | 411
Average Recorded Investment | 387 | 445 | 394 | 454 | 439
Residential: first lien | Loans with Related Allowance |  |  |  |  |
Loan loss allowances, impaired financing receivable |  |  |  |  |
Recorded Investment | 201 |  | 201 |  | 208
Unpaid Principal Balance | 201 |  | 201 |  | 208
Related Allowance | 23 |  | 23 |  | 23
Average Recorded Investment | 202 | 519 | 203 | 1,338 | 214
Residential: first lien | Loans with No Related Allowance |  |  |  |  |
Loan loss allowances, impaired financing receivable |  |  |  |  |
Recorded Investment | 2,551 |  | 2,551 |  | 2,082
Unpaid Principal Balance | 2,588 |  | 2,588 |  | 2,220
Average Recorded Investment | 2,681 | 1,944 | 2,596 | 2,000 | 2,230
Interest Recognized | 11 | 3 | 16 | 3 | 27
Residential: junior lien | Loans with No Related Allowance |  |  |  |  |
Loan loss allowances, impaired financing receivable |  |  |  |  |
Recorded Investment | 1,910 |  | 1,910 |  | 1,962
Unpaid Principal Balance | 1,987 |  | 1,987 |  | 1,970
Average Recorded Investment | 2,113 | 1,531 | 2,119 | 1,535 | 1,980
Interest Recognized | 27 | 48 | 54 | 48 | 118
Consumer | Loans with No Related Allowance |  |  |  |  |
Loan loss allowances, impaired financing receivable |  |  |  |  |
Recorded Investment | 1,080 |  | 1,080 |  | 1,334
Unpaid Principal Balance | 1,081 |  | 1,081 |  | 1,338
Average Recorded Investment | 1,178 | 1,228 | 1,323 | 1,372 | 1,729
Foreign | Loans with No Related Allowance |  |  |  |  |
Loan loss allowances, impaired financing receivable |  |  |  |  |
Recorded Investment | 45 |  | 45 |  | 46
Unpaid Principal Balance | 45 |  | 45 |  | 46
Average Recorded Investment | 45 | 2 | 45 | 3 | 46
Interest Recognized | $ 1 |  | $ 1 |  | $ 4

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- Definition Represents the period of charge off for past due unsecured commercial loans. + References No definition available. + Details
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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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- Definition The interest income recognized during the time within that period that the financing receivables were impaired. + 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)(2) + Details
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