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Allowance for Probable Loan Losses (Aging By Loan Class) (Details) - USD ($) $ in Thousands | Sep. 30, 2016 | Dec. 31, 2015
--- | --- | ---
Financing receivable recorded investment |  |
Past due | $ 59,635 | $ 68,273
Past due 90 days or Greater and Still Accruing | 8,392 | 11,616
Loans, current | 5,827,027 | 5,882,641
Total loans | 5,886,662 | 5,950,914
30 to 59 Days |  |
Financing receivable recorded investment |  |
Past due | 21,807 | 15,584
60 to 89 Days |  |
Financing receivable recorded investment |  |
Past due | 5,820 | 5,219
90 Days or Greater |  |
Financing receivable recorded investment |  |
Past due | 32,008 | 47,470
Commercial |  |
Financing receivable recorded investment |  |
Past due | 24,832 | 32,916
Past due 90 days or Greater and Still Accruing | 2,587 | 2,566
Loans, current | 888,987 | 933,936
Total loans | 913,819 | 966,852
Commercial | 30 to 59 Days |  |
Financing receivable recorded investment |  |
Past due | 6,372 | 3,361
Commercial | 60 to 89 Days |  |
Financing receivable recorded investment |  |
Past due | 1,418 | 940
Commercial | 90 Days or Greater |  |
Financing receivable recorded investment |  |
Past due | 17,042 | 28,615
Commercial Real Estate: Other Construction and Land Development |  |
Financing receivable recorded investment |  |
Past due | 4,235 | 3,988
Past due 90 days or Greater and Still Accruing | 12 |
Loans, current | 1,606,841 | 1,645,839
Total loans | 1,611,076 | 1,649,827
Commercial Real Estate: Other Construction and Land Development | 30 to 59 Days |  |
Financing receivable recorded investment |  |
Past due | 2,366 | 193
Commercial Real Estate: Other Construction and Land Development | 60 to 89 Days |  |
Financing receivable recorded investment |  |
Past due |  | 293
Commercial Real Estate: Other Construction and Land Development | 90 Days or Greater |  |
Financing receivable recorded investment |  |
Past due | 1,869 | 3,502
Commercial Real Estate: Farmland & Commercial |  |
Financing receivable recorded investment |  |
Past due | 14,136 | 12,304
Past due 90 days or Greater and Still Accruing | 1,341 | 3,373
Loans, current | 1,989,727 | 1,983,144
Total loans | 2,003,863 | 1,995,448
Commercial Real Estate: Farmland & Commercial | 30 to 59 Days |  |
Financing receivable recorded investment |  |
Past due | 5,728 | 2,684
Commercial Real Estate: Farmland & Commercial | 60 to 89 Days |  |
Financing receivable recorded investment |  |
Past due | 1,314 | 1,328
Commercial Real Estate: Farmland & Commercial | 90 Days or Greater |  |
Financing receivable recorded investment |  |
Past due | 7,094 | 8,292
Commercial Real Estate: Multifamily |  |
Financing receivable recorded investment |  |
Past due | 957 | 1,317
Past due 90 days or Greater and Still Accruing |  | 49
Loans, current | 117,322 | 138,131
Total loans | 118,279 | 139,448
Commercial Real Estate: Multifamily | 30 to 59 Days |  |
Financing receivable recorded investment |  |
Past due | 194 | 49
Commercial Real Estate: Multifamily | 60 to 89 Days |  |
Financing receivable recorded investment |  |
Past due | 192 | 442
Commercial Real Estate: Multifamily | 90 Days or Greater |  |
Financing receivable recorded investment |  |
Past due | 571 | 826
Residential First Lien |  |
Financing receivable recorded investment |  |
Past due | 9,760 | 11,139
Past due 90 days or Greater and Still Accruing | 3,428 | 4,093
Loans, current | 407,922 | 399,105
Total loans | 417,682 | 410,244
Residential First Lien | 30 to 59 Days |  |
Financing receivable recorded investment |  |
Past due | 3,748 | 5,299
Residential First Lien | 60 to 89 Days |  |
Financing receivable recorded investment |  |
Past due | 2,160 | 1,545
Residential First Lien | 90 Days or Greater |  |
Financing receivable recorded investment |  |
Past due | 3,852 | 4,295
Residential Junior Lien |  |
Financing receivable recorded investment |  |
Past due | 1,770 | 1,772
Past due 90 days or Greater and Still Accruing | 504 | 640
Loans, current | 594,069 | 550,566
Total loans | 595,839 | 552,338
Residential Junior Lien | 30 to 59 Days |  |
Financing receivable recorded investment |  |
Past due | 786 | 713
Residential Junior Lien | 60 to 89 Days |  |
Financing receivable recorded investment |  |
Past due | 312 | 413
Residential Junior Lien | 90 Days or Greater |  |
Financing receivable recorded investment |  |
Past due | 672 | 646
Consumer |  |
Financing receivable recorded investment |  |
Past due | 1,303 | 1,308
Past due 90 days or Greater and Still Accruing | 332 | 453
Loans, current | 54,693 | 56,436
Total loans | 55,996 | 57,744
Consumer | 30 to 59 Days |  |
Financing receivable recorded investment |  |
Past due | 692 | 646
Consumer | 60 to 89 Days |  |
Financing receivable recorded investment |  |
Past due | 277 | 175
Consumer | 90 Days or Greater |  |
Financing receivable recorded investment |  |
Past due | 334 | 487
Foreign |  |
Financing receivable recorded investment |  |
Past due | 2,642 | 3,529
Past due 90 days or Greater and Still Accruing | 188 | 442
Loans, current | 167,466 | 175,484
Total loans | 170,108 | 179,013
Foreign | 30 to 59 Days |  |
Financing receivable recorded investment |  |
Past due | 1,921 | 2,639
Foreign | 60 to 89 Days |  |
Financing receivable recorded investment |  |
Past due | 147 | 83
Foreign | 90 Days or Greater |  |
Financing receivable recorded investment |  |
Past due | $ 574 | $ 807

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