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Allowance for Probable Loan Losses (Aging By Loan Class) (Details) - USD ($) $ in Thousands | Jun. 30, 2018 | Dec. 31, 2017
--- | --- | ---
Financing receivable recorded investment |  |
Past due | $ 50,877 | $ 77,053
Past due 90 days or Greater and Still Accruing | 8,885 | 7,257
Loans, current | 6,388,543 | 6,271,119
Total loans | 6,439,420 | 6,348,172
30 to 59 Days |  |
Financing receivable recorded investment |  |
Past due | 13,551 | 15,855
60 to 89 Days |  |
Financing receivable recorded investment |  |
Past due | 6,649 | 4,429
90 Days or Greater |  |
Financing receivable recorded investment |  |
Past due | 30,677 | 56,769
Commercial |  |
Financing receivable recorded investment |  |
Past due | 21,831 | 22,496
Past due 90 days or Greater and Still Accruing | 618 | 537
Loans, current | 1,068,163 | 1,063,971
Total loans | 1,089,994 | 1,086,467
Commercial | 30 to 59 Days |  |
Financing receivable recorded investment |  |
Past due | 3,192 | 3,790
Commercial | 60 to 89 Days |  |
Financing receivable recorded investment |  |
Past due | 833 | 398
Commercial | 90 Days or Greater |  |
Financing receivable recorded investment |  |
Past due | 17,806 | 18,308
Commercial Real Estate:Other Construction and Land Development |  |
Financing receivable recorded investment |  |
Past due | 4,215 | 1,482
Past due 90 days or Greater and Still Accruing | 2,638 | 6
Loans, current | 1,777,738 | 1,682,068
Total loans | 1,781,953 | 1,683,550
Commercial Real Estate:Other Construction and Land Development | 30 to 59 Days |  |
Financing receivable recorded investment |  |
Past due | 639 | 354
Commercial Real Estate:Other Construction and Land Development | 60 to 89 Days |  |
Financing receivable recorded investment |  |
Past due | 124 | 308
Commercial Real Estate:Other Construction and Land Development | 90 Days or Greater |  |
Financing receivable recorded investment |  |
Past due | 3,452 | 820
Commercial Real Estate: Farmland and Commercial |  |
Financing receivable recorded investment |  |
Past due | 8,799 | 35,576
Past due 90 days or Greater and Still Accruing | 532 | 954
Loans, current | 2,008,968 | 2,007,709
Total loans | 2,017,767 | 2,043,285
Commercial Real Estate: Farmland and Commercial | 30 to 59 Days |  |
Financing receivable recorded investment |  |
Past due | 2,069 | 3,925
Commercial Real Estate: Farmland and Commercial | 60 to 89 Days |  |
Financing receivable recorded investment |  |
Past due | 3,336 | 518
Commercial Real Estate: Farmland and Commercial | 90 Days or Greater |  |
Financing receivable recorded investment |  |
Past due | 3,394 | 31,133
Commercial Real Estate: Multifamily |  |
Financing receivable recorded investment |  |
Past due | 855 | 560
Loans, current | 212,725 | 192,356
Total loans | 213,580 | 192,916
Commercial Real Estate: Multifamily | 30 to 59 Days |  |
Financing receivable recorded investment |  |
Past due | 191 | 84
Commercial Real Estate: Multifamily | 90 Days or Greater |  |
Financing receivable recorded investment |  |
Past due | 664 | 476
Residential First Lien |  |
Financing receivable recorded investment |  |
Past due | 8,340 | 10,848
Past due 90 days or Greater and Still Accruing | 4,053 | 3,861
Loans, current | 418,998 | 421,929
Total loans | 427,338 | 432,777
Residential First Lien | 30 to 59 Days |  |
Financing receivable recorded investment |  |
Past due | 3,343 | 4,295
Residential First Lien | 60 to 89 Days |  |
Financing receivable recorded investment |  |
Past due | 699 | 2,458
Residential First Lien | 90 Days or Greater |  |
Financing receivable recorded investment |  |
Past due | 4,298 | 4,095
Residential Junior Lien |  |
Financing receivable recorded investment |  |
Past due | 2,508 | 3,000
Past due 90 days or Greater and Still Accruing | 994 | 1,099
Loans, current | 707,075 | 697,748
Total loans | 709,583 | 700,748
Residential Junior Lien | 30 to 59 Days |  |
Financing receivable recorded investment |  |
Past due | 1,230 | 1,310
Residential Junior Lien | 60 to 89 Days |  |
Financing receivable recorded investment |  |
Past due | 284 | 580
Residential Junior Lien | 90 Days or Greater |  |
Financing receivable recorded investment |  |
Past due | 994 | 1,110
Consumer |  |
Financing receivable recorded investment |  |
Past due | 638 | 1,126
Past due 90 days or Greater and Still Accruing | 36 | 133
Loans, current | 47,109 | 48,417
Total loans | 47,747 | 49,543
Consumer | 30 to 59 Days |  |
Financing receivable recorded investment |  |
Past due | 532 | 868
Consumer | 60 to 89 Days |  |
Financing receivable recorded investment |  |
Past due | 51 | 98
Consumer | 90 Days or Greater |  |
Financing receivable recorded investment |  |
Past due | 55 | 160
Foreign |  |
Financing receivable recorded investment |  |
Past due | 3,691 | 1,965
Past due 90 days or Greater and Still Accruing | 14 | 667
Loans, current | 147,767 | 156,921
Total loans | 151,458 | 158,886
Foreign | 30 to 59 Days |  |
Financing receivable recorded investment |  |
Past due | 2,355 | 1,229
Foreign | 60 to 89 Days |  |
Financing receivable recorded investment |  |
Past due | 1,322 | 69
Foreign | 90 Days or Greater |  |
Financing receivable recorded investment |  |
Past due | $ 14 | $ 667

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