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Allowance for Probable Loan Losses (Aging By Loan Class) (Details) - USD ($) $ in Thousands | Mar. 31, 2016 | Dec. 31, 2015
--- | --- | ---
Financing receivable recorded investment |  |
Past due | $ 65,097 | $ 68,273
Past due 90 days or greater and still accruing | 8,558 | 11,616
Loans, current | 5,870,477 | 5,882,641
Total loans | 5,935,574 | 5,950,914
30 to 59 Days |  |
Financing receivable recorded investment |  |
Past due | 29,856 | 15,584
60 to 89 Days |  |
Financing receivable recorded investment |  |
Past due | 5,746 | 5,219
90 Days or Greater |  |
Financing receivable recorded investment |  |
Past due | 29,495 | 47,470
Commercial |  |
Financing receivable recorded investment |  |
Past due | 28,534 | 32,916
Past due 90 days or greater and still accruing | 392 | 2,566
Loans, current | 917,641 | 933,936
Total loans | 946,175 | 966,852
Commercial | 30 to 59 Days |  |
Financing receivable recorded investment |  |
Past due | 16,109 | 3,361
Commercial | 60 to 89 Days |  |
Financing receivable recorded investment |  |
Past due | 2,069 | 940
Commercial | 90 Days or Greater |  |
Financing receivable recorded investment |  |
Past due | 10,356 | 28,615
Commercial Real Estate: Other Construction and Land Development |  |
Financing receivable recorded investment |  |
Past due | 7,035 | 3,988
Past due 90 days or greater and still accruing | 125 |
Loans, current | 1,701,117 | 1,645,839
Total loans | 1,708,152 | 1,649,827
Commercial Real Estate: Other Construction and Land Development | 30 to 59 Days |  |
Financing receivable recorded investment |  |
Past due | 3,590 | 193
Commercial Real Estate: Other Construction and Land Development | 60 to 89 Days |  |
Financing receivable recorded investment |  |
Past due | 273 | 293
Commercial Real Estate: Other Construction and Land Development | 90 Days or Greater |  |
Financing receivable recorded investment |  |
Past due | 3,172 | 3,502
Commercial Real Estate: Farmland & Commercial |  |
Financing receivable recorded investment |  |
Past due | 14,165 | 12,304
Past due 90 days or greater and still accruing | 1,642 | 3,373
Loans, current | 1,916,693 | 1,983,144
Total loans | 1,930,858 | 1,995,448
Commercial Real Estate: Farmland & Commercial | 30 to 59 Days |  |
Financing receivable recorded investment |  |
Past due | 4,399 | 2,684
Commercial Real Estate: Farmland & Commercial | 60 to 89 Days |  |
Financing receivable recorded investment |  |
Past due | 1,021 | 1,328
Commercial Real Estate: Farmland & Commercial | 90 Days or Greater |  |
Financing receivable recorded investment |  |
Past due | 8,745 | 8,292
Commercial Real Estate: Multifamily |  |
Financing receivable recorded investment |  |
Past due | 653 | 1,317
Past due 90 days or greater and still accruing | 442 | 49
Loans, current | 147,918 | 138,131
Total loans | 148,571 | 139,448
Commercial Real Estate: Multifamily | 30 to 59 Days |  |
Financing receivable recorded investment |  |
Past due | 47 | 49
Commercial Real Estate: Multifamily | 60 to 89 Days |  |
Financing receivable recorded investment |  |
Past due |  | 442
Commercial Real Estate: Multifamily | 90 Days or Greater |  |
Financing receivable recorded investment |  |
Past due | 606 | 826
Residential First Lien |  |
Financing receivable recorded investment |  |
Past due | 9,937 | 11,139
Past due 90 days or greater and still accruing | 4,513 | 4,093
Loans, current | 402,403 | 399,105
Total loans | 412,340 | 410,244
Residential First Lien | 30 to 59 Days |  |
Financing receivable recorded investment |  |
Past due | 3,599 | 5,299
Residential First Lien | 60 to 89 Days |  |
Financing receivable recorded investment |  |
Past due | 1,598 | 1,545
Residential First Lien | 90 Days or Greater |  |
Financing receivable recorded investment |  |
Past due | 4,740 | 4,295
Residential Junior Lien |  |
Financing receivable recorded investment |  |
Past due | 1,606 | 1,772
Past due 90 days or greater and still accruing | 613 | 640
Loans, current | 555,266 | 550,566
Total loans | 556,872 | 552,338
Residential Junior Lien | 30 to 59 Days |  |
Financing receivable recorded investment |  |
Past due | 499 | 713
Residential Junior Lien | 60 to 89 Days |  |
Financing receivable recorded investment |  |
Past due | 462 | 413
Residential Junior Lien | 90 Days or Greater |  |
Financing receivable recorded investment |  |
Past due | 645 | 646
Consumer |  |
Financing receivable recorded investment |  |
Past due | 1,404 | 1,308
Past due 90 days or greater and still accruing | 409 | 453
Loans, current | 54,521 | 56,436
Total loans | 55,925 | 57,744
Consumer | 30 to 59 Days |  |
Financing receivable recorded investment |  |
Past due | 704 | 646
Consumer | 60 to 89 Days |  |
Financing receivable recorded investment |  |
Past due | 256 | 175
Consumer | 90 Days or Greater |  |
Financing receivable recorded investment |  |
Past due | 444 | 487
Foreign |  |
Financing receivable recorded investment |  |
Past due | 1,763 | 3,529
Past due 90 days or greater and still accruing | 422 | 442
Loans, current | 174,918 | 175,484
Total loans | 176,681 | 179,013
Foreign | 30 to 59 Days |  |
Financing receivable recorded investment |  |
Past due | 909 | 2,639
Foreign | 60 to 89 Days |  |
Financing receivable recorded investment |  |
Past due | 67 | 83
Foreign | 90 Days or Greater |  |
Financing receivable recorded investment |  |
Past due | $ 787 | $ 807

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