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Allowance for Probable Loan Losses (Details 4) (USD $) In Thousands, unless otherwise specified | 12 Months Ended
--- | ---
Dec. 31, 2012 | Dec. 31, 2011
Interest income recognized: |  |
Period of charge off for past due unsecured commercial loans | 90 days |
Class of financing receivable |  |
Recorded investment: |  |
Total impaired loans with related allowance | $ 11,982 | $ 87,369
Total impaired loans with no related allowance | 71,023 | 48,936
Unpaid principal balance: |  |
Total impaired loans with an allowance recorded | 15,273 | 87,419
Total impaired loans with no related allowance recorded | 73,728 | 49,551
Related Allowance | 4,746 | 27,252
Average recorded investment: |  |
Total impaired loans with an allowance recorded | 35,076 | 79,852
Total impaired loans with no related allowance recorded | 65,536 | 40,966
Interest income recognized: |  |
Total impaired loans with an allowance recorded | 131 | 858
Total impaired loans with no related allowance recorded | 323 | 372
Commercial | Class of financing receivable |  |
Recorded investment: |  |
Total impaired loans with related allowance | 1,633 | 24,108
Total impaired loans with no related allowance | 31,135 | 3,495
Unpaid principal balance: |  |
Total impaired loans with an allowance recorded | 1,679 | 24,108
Total impaired loans with no related allowance recorded | 31,170 | 3,500
Related Allowance | 1,477 | 14,402
Average recorded investment: |  |
Total impaired loans with an allowance recorded | 21,126 | 23,101
Total impaired loans with no related allowance recorded | 2,996 | 685
Interest income recognized: |  |
Total impaired loans with an allowance recorded | 39 | 41
Total impaired loans with no related allowance recorded | 4 |
Commercial real estate: other construction and land development | Class of financing receivable |  |
Recorded investment: |  |
Total impaired loans with related allowance | 3,671 | 34,417
Total impaired loans with no related allowance | 24,989 | 26,011
Unpaid principal balance: |  |
Total impaired loans with an allowance recorded | 3,671 | 34,432
Total impaired loans with no related allowance recorded | 25,160 | 26,042
Related Allowance | 539 | 3,073
Average recorded investment: |  |
Total impaired loans with an allowance recorded | 6,608 | 32,408
Total impaired loans with no related allowance recorded | 39,449 | 25,696
Interest income recognized: |  |
Total impaired loans with no related allowance recorded | 141 | 117
Commercial real estate: farmland and commercial | Class of financing receivable |  |
Recorded investment: |  |
Total impaired loans with related allowance | 6,678 | 28,636
Total impaired loans with no related allowance | 7,267 | 13,595
Unpaid principal balance: |  |
Total impaired loans with an allowance recorded | 9,923 | 28,671
Total impaired loans with no related allowance recorded | 9,340 | 14,129
Related Allowance | 2,730 | 9,754
Average recorded investment: |  |
Total impaired loans with an allowance recorded | 7,342 | 23,226
Total impaired loans with no related allowance recorded | 16,536 | 9,268
Interest income recognized: |  |
Total impaired loans with an allowance recorded | 92 | 817
Total impaired loans with no related allowance recorded | 8 | 102
Commercial real estate: multifamily | Class of financing receivable |  |
Recorded investment: |  |
Total impaired loans with no related allowance | 353 | 411
Unpaid principal balance: |  |
Total impaired loans with no related allowance recorded | 353 | 411
Average recorded investment: |  |
Total impaired loans with no related allowance recorded | 381 | 439
Residential: first lien | Class of financing receivable |  |
Recorded investment: |  |
Total impaired loans with related allowance |  | 208
Total impaired loans with no related allowance | 3,656 | 2,082
Unpaid principal balance: |  |
Total impaired loans with an allowance recorded |  | 208
Total impaired loans with no related allowance recorded | 3,984 | 2,116
Related Allowance |  | 23
Average recorded investment: |  |
Total impaired loans with an allowance recorded |  | 1,117
Total impaired loans with no related allowance recorded | 2,876 | 1,636
Interest income recognized: |  |
Total impaired loans with no related allowance recorded | 60 | 27
Residential: junior lien | Class of financing receivable |  |
Recorded investment: |  |
Total impaired loans with no related allowance | 1,850 | 1,962
Unpaid principal balance: |  |
Total impaired loans with no related allowance recorded | 1,944 | 1,970
Average recorded investment: |  |
Total impaired loans with no related allowance recorded | 1,939 | 1,956
Interest income recognized: |  |
Total impaired loans with no related allowance recorded | 104 | 122
Consumer | Class of financing receivable |  |
Recorded investment: |  |
Total impaired loans with no related allowance | 1,326 | 1,334
Unpaid principal balance: |  |
Total impaired loans with no related allowance recorded | 1,330 | 1,337
Average recorded investment: |  |
Total impaired loans with no related allowance recorded | 1,193 | 1,239
Foreign | Class of financing receivable |  |
Recorded investment: |  |
Total impaired loans with no related allowance | 447 | 46
Unpaid principal balance: |  |
Total impaired loans with no related allowance recorded | 447 | 46
Average recorded investment: |  |
Total impaired loans with no related allowance recorded | 166 | 47
Interest income recognized: |  |
Total impaired loans with no related allowance recorded | $ 6 | $ 4

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