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Allowance for Probable Loan Losses (Details 4) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | ---
Sep. 30, 2015 | Sep. 30, 2014 | Sep. 30, 2015 | Sep. 30, 2014 | Dec. 31, 2014
Interest Recognized |  |  |  |  |
Total trouble debt restructuring | $ 15,432 |  | $ 15,432 |  | $ 15,653
Period of charge off for past due unsecured commercial loans |  |  | 90 days |  |
Class of financing receivable |  |  |  |  |
Recorded investment: |  |  |  |  |
Total impaired loans with related allowance | 13,970 |  | $ 13,970 |  | 31,765
Total impaired loans with no related allowance | 42,412 |  | 42,412 |  | 44,406
Unpaid principal balance: |  |  |  |  |
Total impaired loans with an allowance recorded | 25,735 |  | 25,735 |  | 32,232
Total impaired loans with no related allowance recorded | 44,586 |  | 44,586 |  | 46,262
Related Allowance | 1,756 |  | 1,756 |  | 12,221
Average recorded investment: |  |  |  |  |
Total impaired loans with an allowance recorded | 14,934 | $ 32,525 | 20,816 | $ 31,715 | 33,286
Total impaired loans with no related allowance recorded | 42,643 | 44,599 | 43,580 | 44,532 | 43,202
Interest Recognized |  |  |  |  |
Total impaired loans with an allowance recorded | 23 | 23 | 69 | 69 | 92
Total impaired loans with no related allowance recorded | 106 | 112 | 318 | 336 | 444
Commercial |  |  |  |  |
Interest Recognized |  |  |  |  |
Total trouble debt restructuring | 2,420 |  | 2,420 |  | 2,500
Commercial | Class of financing receivable |  |  |  |  |
Recorded investment: |  |  |  |  |
Total impaired loans with related allowance | 10,288 |  | 10,288 |  | 19,944
Total impaired loans with no related allowance | 20,977 |  | 20,977 |  | 20,231
Unpaid principal balance: |  |  |  |  |
Total impaired loans with an allowance recorded | 21,840 |  | 21,840 |  | 20,026
Total impaired loans with no related allowance recorded | 21,909 |  | 21,909 |  | 20,260
Related Allowance | 1,174 |  | 1,174 |  | 9,112
Average recorded investment: |  |  |  |  |
Total impaired loans with an allowance recorded | 11,247 | 17,677 | 15,634 | 17,550 | 19,313
Total impaired loans with no related allowance recorded | 21,291 | 21,265 | 20,623 | 19,557 | 18,563
Interest Recognized |  |  |  |  |
Total impaired loans with no related allowance recorded | 1 | 1 | 3 | 3 | 4
Commercial Real Estate: Other Construction and Land Development |  |  |  |  |
Interest Recognized |  |  |  |  |
Total trouble debt restructuring | 2,553 |  | 2,553 |  | 2,254
Commercial Real Estate: Other Construction and Land Development | Class of financing receivable |  |  |  |  |
Recorded investment: |  |  |  |  |
Total impaired loans with related allowance | 169 |  | 169 |  | 6,714
Total impaired loans with no related allowance | 6,180 |  | 6,180 |  | 4,162
Unpaid principal balance: |  |  |  |  |
Total impaired loans with an allowance recorded | 169 |  | 169 |  | 6,949
Total impaired loans with no related allowance recorded | 6,206 |  | 6,206 |  | 4,270
Related Allowance | 100 |  | 100 |  | 1,890
Average recorded investment: |  |  |  |  |
Total impaired loans with an allowance recorded | 170 | 7,329 | 1,136 | 7,326 | 7,183
Total impaired loans with no related allowance recorded | 6,045 | 4,192 | 6,561 | 5,121 | 4,882
Interest Recognized |  |  |  |  |
Total impaired loans with no related allowance recorded | 20 | 19 | 57 | 56 | 74
Commercial real estate: farmland and commercial |  |  |  |  |
Interest Recognized |  |  |  |  |
Total trouble debt restructuring | 2,853 |  | 2,853 |  | 2,861
Commercial real estate: farmland and commercial | Class of financing receivable |  |  |  |  |
Recorded investment: |  |  |  |  |
Total impaired loans with related allowance | 3,513 |  | 3,513 |  | 5,107
Total impaired loans with no related allowance | 6,129 |  | 6,129 |  | 9,059
Unpaid principal balance: |  |  |  |  |
Total impaired loans with an allowance recorded | 3,726 |  | 3,726 |  | 5,257
Total impaired loans with no related allowance recorded | 7,263 |  | 7,263 |  | 10,562
Related Allowance | 482 |  | 482 |  | 1,219
Average recorded investment: |  |  |  |  |
Total impaired loans with an allowance recorded | 3,517 | 7,519 | 4,046 | 6,839 | 6,790
Total impaired loans with no related allowance recorded | 6,203 | 8,418 | 7,253 | 8,643 | 8,664
Interest Recognized |  |  |  |  |
Total impaired loans with an allowance recorded | 23 | 23 | 69 | 69 | 92
Commercial real estate: multifamily |  |  |  |  |
Interest Recognized |  |  |  |  |
Total trouble debt restructuring | 21 |  | 21 |  |
Commercial real estate: multifamily | Class of financing receivable |  |  |  |  |
Recorded investment: |  |  |  |  |
Total impaired loans with no related allowance | 812 |  | 812 |  | 835
Unpaid principal balance: |  |  |  |  |
Total impaired loans with no related allowance recorded | 812 |  | 812 |  | 835
Average recorded investment: |  |  |  |  |
Total impaired loans with no related allowance recorded | 819 | 256 | 832 | 270 | 363
Interest Recognized |  |  |  |  |
Total impaired loans with no related allowance recorded |  |  | 1 |  |
Residential: first lien |  |  |  |  |
Interest Recognized |  |  |  |  |
Total trouble debt restructuring | 4,972 |  | 4,972 |  | 5,313
Residential: first lien | Class of financing receivable |  |  |  |  |
Recorded investment: |  |  |  |  |
Total impaired loans with no related allowance | 5,294 |  | 5,294 |  | 5,840
Unpaid principal balance: |  |  |  |  |
Total impaired loans with no related allowance recorded | 5,353 |  | 5,353 |  | 6,034
Average recorded investment: |  |  |  |  |
Total impaired loans with no related allowance recorded | 5,315 | 5,648 | 5,375 | 6,028 | 6,293
Interest Recognized |  |  |  |  |
Total impaired loans with no related allowance recorded | 65 | 64 | 188 | 191 | 273
Residential: junior lien |  |  |  |  |
Interest Recognized |  |  |  |  |
Total trouble debt restructuring | 1,012 |  | 1,012 |  | 1,371
Residential: junior lien | Class of financing receivable |  |  |  |  |
Recorded investment: |  |  |  |  |
Total impaired loans with no related allowance | 1,028 |  | 1,028 |  | 2,895
Unpaid principal balance: |  |  |  |  |
Total impaired loans with no related allowance recorded | 1,050 |  | 1,050 |  | 2,915
Average recorded investment: |  |  |  |  |
Total impaired loans with no related allowance recorded | 1,075 | 2,992 | 1,255 | 3,080 | 3,035
Interest Recognized |  |  |  |  |
Total impaired loans with no related allowance recorded | 15 | 22 | 54 | 69 | 90
Consumer |  |  |  |  |
Interest Recognized |  |  |  |  |
Total trouble debt restructuring | 1,208 |  | 1,208 |  | 1,354
Consumer | Class of financing receivable |  |  |  |  |
Recorded investment: |  |  |  |  |
Total impaired loans with no related allowance | 1,243 |  | 1,243 |  | 1,384
Unpaid principal balance: |  |  |  |  |
Total impaired loans with no related allowance recorded | 1,244 |  | 1,244 |  | 1,386
Average recorded investment: |  |  |  |  |
Total impaired loans with no related allowance recorded | 1,263 | 1,408 | 1,201 | 1,407 | 1,402
Interest Recognized |  |  |  |  |
Total impaired loans with no related allowance recorded | 1 | 1 | 2 | 3 | $ 3
Foreign |  |  |  |  |
Interest Recognized |  |  |  |  |
Total trouble debt restructuring | 393 |  | 393 |  |
Foreign | Class of financing receivable |  |  |  |  |
Recorded investment: |  |  |  |  |
Total impaired loans with no related allowance | 749 |  | 749 |  |
Unpaid principal balance: |  |  |  |  |
Total impaired loans with no related allowance recorded | 749 |  | 749 |  |
Average recorded investment: |  |  |  |  |
Total impaired loans with no related allowance recorded | 632 | 420 | 480 | 426 |
Interest Recognized |  |  |  |  |
Total impaired loans with no related allowance recorded | $ 4 | $ 5 | $ 13 | $ 14 |

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