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Allowance for Probable Loan Losses (Aging By Loan Class) (Details) - USD ($) $ in Thousands | Mar. 31, 2017 | Dec. 31, 2016
--- | --- | ---
Financing receivable recorded investment |  |
Past due | $ 53,434 | $ 61,400
Past due 90 days or Greater and Still Accruing | 8,981 | 5,226
Loans, current | 5,956,069 | 5,903,288
Total loans | 6,009,503 | 5,964,688
30 to 59 Days |  |
Financing receivable recorded investment |  |
Past due | 14,160 | 17,299
60 to 89 Days |  |
Financing receivable recorded investment |  |
Past due | 4,156 | 6,327
90 Days or Greater |  |
Financing receivable recorded investment |  |
Past due | 35,118 | 37,774
Commercial |  |
Financing receivable recorded investment |  |
Past due | 24,448 | 26,033
Past due 90 days or Greater and Still Accruing | 781 | 392
Loans, current | 839,745 | 883,634
Total loans | 864,193 | 909,667
Commercial | 30 to 59 Days |  |
Financing receivable recorded investment |  |
Past due | 3,048 | 4,081
Commercial | 60 to 89 Days |  |
Financing receivable recorded investment |  |
Past due | 796 | 829
Commercial | 90 Days or Greater |  |
Financing receivable recorded investment |  |
Past due | 20,604 | 21,123
Commercial Real Estate: Other Construction and Land Development |  |
Financing receivable recorded investment |  |
Past due | 4,727 | 6,354
Past due 90 days or Greater and Still Accruing | 6 | 9
Loans, current | 1,773,555 | 1,710,521
Total loans | 1,778,282 | 1,716,875
Commercial Real Estate: Other Construction and Land Development | 30 to 59 Days |  |
Financing receivable recorded investment |  |
Past due | 2,659 | 1,502
Commercial Real Estate: Other Construction and Land Development | 60 to 89 Days |  |
Financing receivable recorded investment |  |
Past due | 375 | 396
Commercial Real Estate: Other Construction and Land Development | 90 Days or Greater |  |
Financing receivable recorded investment |  |
Past due | 1,693 | 4,456
Commercial Real Estate: Farmland & Commercial |  |
Financing receivable recorded investment |  |
Past due | 8,929 | 12,658
Past due 90 days or Greater and Still Accruing | 3,104 | 289
Loans, current | 1,948,743 | 1,930,412
Total loans | 1,957,672 | 1,943,070
Commercial Real Estate: Farmland & Commercial | 30 to 59 Days |  |
Financing receivable recorded investment |  |
Past due | 1,406 | 3,454
Commercial Real Estate: Farmland & Commercial | 60 to 89 Days |  |
Financing receivable recorded investment |  |
Past due | 1,290 | 3,054
Commercial Real Estate: Farmland & Commercial | 90 Days or Greater |  |
Financing receivable recorded investment |  |
Past due | 6,233 | 6,150
Commercial Real Estate: Multifamily |  |
Financing receivable recorded investment |  |
Past due | 532 | 596
Loans, current | 144,566 | 139,870
Total loans | 145,098 | 140,466
Commercial Real Estate: Multifamily | 30 to 59 Days |  |
Financing receivable recorded investment |  |
Past due |  | 44
Commercial Real Estate: Multifamily | 90 Days or Greater |  |
Financing receivable recorded investment |  |
Past due | 532 | 552
Residential First Lien |  |
Financing receivable recorded investment |  |
Past due | 8,570 | 11,108
Past due 90 days or Greater and Still Accruing | 4,296 | 3,756
Loans, current | 409,964 | 410,796
Total loans | 418,534 | 421,904
Residential First Lien | 30 to 59 Days |  |
Financing receivable recorded investment |  |
Past due | 2,960 | 5,615
Residential First Lien | 60 to 89 Days |  |
Financing receivable recorded investment |  |
Past due | 933 | 1,350
Residential First Lien | 90 Days or Greater |  |
Financing receivable recorded investment |  |
Past due | 4,677 | 4,143
Residential Junior Lien |  |
Financing receivable recorded investment |  |
Past due | 1,269 | 1,480
Past due 90 days or Greater and Still Accruing | 343 | 382
Loans, current | 627,212 | 608,838
Total loans | 628,481 | 610,318
Residential Junior Lien | 30 to 59 Days |  |
Financing receivable recorded investment |  |
Past due | 739 | 762
Residential Junior Lien | 60 to 89 Days |  |
Financing receivable recorded investment |  |
Past due | 30 | 178
Residential Junior Lien | 90 Days or Greater |  |
Financing receivable recorded investment |  |
Past due | 500 | 540
Consumer |  |
Financing receivable recorded investment |  |
Past due | 977 | 1,418
Past due 90 days or Greater and Still Accruing | 329 | 387
Loans, current | 52,637 | 53,750
Total loans | 53,614 | 55,168
Consumer | 30 to 59 Days |  |
Financing receivable recorded investment |  |
Past due | 516 | 910
Consumer | 60 to 89 Days |  |
Financing receivable recorded investment |  |
Past due | 94 | 95
Consumer | 90 Days or Greater |  |
Financing receivable recorded investment |  |
Past due | 367 | 413
Foreign |  |
Financing receivable recorded investment |  |
Past due | 3,982 | 1,753
Past due 90 days or Greater and Still Accruing | 122 | 11
Loans, current | 159,647 | 165,467
Total loans | 163,629 | 167,220
Foreign | 30 to 59 Days |  |
Financing receivable recorded investment |  |
Past due | 2,832 | 931
Foreign | 60 to 89 Days |  |
Financing receivable recorded investment |  |
Past due | 638 | 425
Foreign | 90 Days or Greater |  |
Financing receivable recorded investment |  |
Past due | $ 512 | $ 397

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