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Allowance for Probable Loan Losses (Aging By Loan Class) (Details) - USD ($) $ in Thousands | Jun. 30, 2016 | Dec. 31, 2015
--- | --- | ---
Financing receivable recorded investment |  |
Past due | $ 59,230 | $ 68,273
Past due 90 days or Greater and Still Accruing | 7,028 | 11,616
Loans, current | 5,892,367 | 5,882,641
Total loans | 5,951,597 | 5,950,914
30 to 59 Days |  |
Financing receivable recorded investment |  |
Past due | 28,996 | 15,584
60 to 89 Days |  |
Financing receivable recorded investment |  |
Past due | 6,822 | 5,219
90 Days or Greater |  |
Financing receivable recorded investment |  |
Past due | 23,412 | 47,470
Commercial |  |
Financing receivable recorded investment |  |
Past due | 20,726 | 32,916
Past due 90 days or Greater and Still Accruing | 2,549 | 2,566
Loans, current | 921,226 | 933,936
Total loans | 941,952 | 966,852
Commercial | 30 to 59 Days |  |
Financing receivable recorded investment |  |
Past due | 8,830 | 3,361
Commercial | 60 to 89 Days |  |
Financing receivable recorded investment |  |
Past due | 1,078 | 940
Commercial | 90 Days or Greater |  |
Financing receivable recorded investment |  |
Past due | 10,818 | 28,615
Commercial Real Estate: Other Construction and Land Development |  |
Financing receivable recorded investment |  |
Past due | 4,857 | 3,988
Past due 90 days or Greater and Still Accruing | 143 |
Loans, current | 1,681,254 | 1,645,839
Total loans | 1,686,111 | 1,649,827
Commercial Real Estate: Other Construction and Land Development | 30 to 59 Days |  |
Financing receivable recorded investment |  |
Past due | 2,404 | 193
Commercial Real Estate: Other Construction and Land Development | 60 to 89 Days |  |
Financing receivable recorded investment |  |
Past due | 199 | 293
Commercial Real Estate: Other Construction and Land Development | 90 Days or Greater |  |
Financing receivable recorded investment |  |
Past due | 2,254 | 3,502
Commercial Real Estate: Farmland & Commercial |  |
Financing receivable recorded investment |  |
Past due | 16,852 | 12,304
Past due 90 days or Greater and Still Accruing | 189 | 3,373
Loans, current | 1,936,919 | 1,983,144
Total loans | 1,953,771 | 1,995,448
Commercial Real Estate: Farmland & Commercial | 30 to 59 Days |  |
Financing receivable recorded investment |  |
Past due | 9,269 | 2,684
Commercial Real Estate: Farmland & Commercial | 60 to 89 Days |  |
Financing receivable recorded investment |  |
Past due | 2,940 | 1,328
Commercial Real Estate: Farmland & Commercial | 90 Days or Greater |  |
Financing receivable recorded investment |  |
Past due | 4,643 | 8,292
Commercial Real Estate: Multifamily |  |
Financing receivable recorded investment |  |
Past due | 1,686 | 1,317
Past due 90 days or Greater and Still Accruing |  | 49
Loans, current | 137,740 | 138,131
Total loans | 139,426 | 139,448
Commercial Real Estate: Multifamily | 30 to 59 Days |  |
Financing receivable recorded investment |  |
Past due | 721 | 49
Commercial Real Estate: Multifamily | 60 to 89 Days |  |
Financing receivable recorded investment |  |
Past due | 375 | 442
Commercial Real Estate: Multifamily | 90 Days or Greater |  |
Financing receivable recorded investment |  |
Past due | 590 | 826
Residential First Lien |  |
Financing receivable recorded investment |  |
Past due | 9,297 | 11,139
Past due 90 days or Greater and Still Accruing | 3,135 | 4,093
Loans, current | 406,579 | 399,105
Total loans | 415,876 | 410,244
Residential First Lien | 30 to 59 Days |  |
Financing receivable recorded investment |  |
Past due | 4,349 | 5,299
Residential First Lien | 60 to 89 Days |  |
Financing receivable recorded investment |  |
Past due | 1,401 | 1,545
Residential First Lien | 90 Days or Greater |  |
Financing receivable recorded investment |  |
Past due | 3,547 | 4,295
Residential Junior Lien |  |
Financing receivable recorded investment |  |
Past due | 1,460 | 1,772
Past due 90 days or Greater and Still Accruing | 325 | 640
Loans, current | 579,973 | 550,566
Total loans | 581,433 | 552,338
Residential Junior Lien | 30 to 59 Days |  |
Financing receivable recorded investment |  |
Past due | 710 | 713
Residential Junior Lien | 60 to 89 Days |  |
Financing receivable recorded investment |  |
Past due | 256 | 413
Residential Junior Lien | 90 Days or Greater |  |
Financing receivable recorded investment |  |
Past due | 494 | 646
Consumer |  |
Financing receivable recorded investment |  |
Past due | 1,817 | 1,308
Past due 90 days or Greater and Still Accruing | 381 | 453
Loans, current | 54,300 | 56,436
Total loans | 56,117 | 57,744
Consumer | 30 to 59 Days |  |
Financing receivable recorded investment |  |
Past due | 1,246 | 646
Consumer | 60 to 89 Days |  |
Financing receivable recorded investment |  |
Past due | 190 | 175
Consumer | 90 Days or Greater |  |
Financing receivable recorded investment |  |
Past due | 381 | 487
Foreign |  |
Financing receivable recorded investment |  |
Past due | 2,535 | 3,529
Past due 90 days or Greater and Still Accruing | 306 | 442
Loans, current | 174,376 | 175,484
Total loans | 176,911 | 179,013
Foreign | 30 to 59 Days |  |
Financing receivable recorded investment |  |
Past due | 1,467 | 2,639
Foreign | 60 to 89 Days |  |
Financing receivable recorded investment |  |
Past due | 383 | 83
Foreign | 90 Days or Greater |  |
Financing receivable recorded investment |  |
Past due | $ 685 | $ 807

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