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Allowance for Probable Loan Losses (Portfolio Credit Quality By Loan Class) (Details) - USD ($) $ in Thousands | Jun. 30, 2018 | Dec. 31, 2017
--- | --- | ---
Loan portfolio by credit quality indicator |  |
Portfolio, total | $ 6,439,420 | $ 6,348,172
Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 6,021,949 | 5,911,001
Special Review |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 58,494 | 6,612
Watch List - Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 48,585 | 45,662
Watch List - Substandard |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 274,952 | 321,693
Watch - List Impaired |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 35,440 | 63,204
Commercial |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 1,089,994 | 1,086,467
Commercial | Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 951,055 | 905,707
Commercial | Special Review |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 256 |
Commercial | Watch List - Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 1,034 | 3,170
Commercial | Watch List - Substandard |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 119,716 | 159,643
Commercial | Watch - List Impaired |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 17,933 | 17,947
Commercial Real Estate:Other Construction and Land Development |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 1,781,953 | 1,683,550
Commercial Real Estate:Other Construction and Land Development | Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 1,715,667 | 1,616,604
Commercial Real Estate:Other Construction and Land Development | Special Review |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 1,115 | 1,288
Commercial Real Estate:Other Construction and Land Development | Watch List - Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 7,169 | 672
Commercial Real Estate:Other Construction and Land Development | Watch List - Substandard |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 55,836 | 62,531
Commercial Real Estate:Other Construction and Land Development | Watch - List Impaired |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 2,166 | 2,455
Commercial Real Estate: Farmland and Commercial |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 2,017,767 | 2,043,285
Commercial Real Estate: Farmland and Commercial | Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 1,817,420 | 1,863,763
Commercial Real Estate: Farmland and Commercial | Special Review |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 57,123 | 5,134
Commercial Real Estate: Farmland and Commercial | Watch List - Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 39,372 | 41,820
Commercial Real Estate: Farmland and Commercial | Watch List - Substandard |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 97,832 | 99,445
Commercial Real Estate: Farmland and Commercial | Watch - List Impaired |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 6,020 | 33,123
Commercial Real Estate: Multifamily |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 213,580 | 192,916
Commercial Real Estate: Multifamily | Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 211,972 | 192,440
Commercial Real Estate: Multifamily | Watch List - Substandard |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 944 |
Commercial Real Estate: Multifamily | Watch - List Impaired |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 664 | 476
Residential First Lien |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 427,338 | 432,777
Residential First Lien | Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 420,198 | 425,811
Residential First Lien | Special Review |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total |  | 40
Residential First Lien | Watch List - Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 129 |
Residential First Lien | Watch List - Substandard |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 624 | 74
Residential First Lien | Watch - List Impaired |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 6,387 | 6,852
Residential Junior Lien |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 709,583 | 700,748
Residential Junior Lien | Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 707,903 | 699,875
Residential Junior Lien | Special Review |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total |  | 150
Residential Junior Lien | Watch List - Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 881 |
Residential Junior Lien | Watch - List Impaired |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 799 | 723
Consumer |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 47,747 | 49,543
Consumer | Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 46,606 | 48,262
Consumer | Watch - List Impaired |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 1,141 | 1,281
Foreign |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 151,458 | 158,886
Foreign | Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 151,128 | 158,539
Foreign | Watch - List Impaired |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | $ 330 | $ 347

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