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Allowance for Probable Loan Losses (Portfolio Credit Quality By Loan Class) (Details) - USD ($) $ in Thousands | Sep. 30, 2018 | Dec. 31, 2017
--- | --- | ---
Loan portfolio by credit quality indicator |  |
Portfolio, total | $ 6,475,141 | $ 6,348,172
Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 6,055,035 | 5,911,001
Special Review |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 61,544 | 6,612
Watch List - Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 85,273 | 45,662
Watch List - Substandard |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 240,797 | 321,693
Watch - List Impaired |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 32,492 | 63,204
Commercial |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 1,078,565 | 1,086,467
Commercial | Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 959,115 | 905,707
Commercial | Special Review |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 449 |
Commercial | Watch List - Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 38,469 | 3,170
Commercial | Watch List - Substandard |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 63,296 | 159,643
Commercial | Watch - List Impaired |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 17,236 | 17,947
Commercial Real Estate:Other Construction and Land Development |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 1,878,440 | 1,683,550
Commercial Real Estate:Other Construction and Land Development | Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 1,811,960 | 1,616,604
Commercial Real Estate:Other Construction and Land Development | Special Review |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 1,662 | 1,288
Commercial Real Estate:Other Construction and Land Development | Watch List - Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 7,171 | 672
Commercial Real Estate:Other Construction and Land Development | Watch List - Substandard |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 55,517 | 62,531
Commercial Real Estate:Other Construction and Land Development | Watch - List Impaired |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 2,130 | 2,455
Commercial Real Estate: Farmland and Commercial |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 1,981,554 | 2,043,285
Commercial Real Estate: Farmland and Commercial | Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 1,759,210 | 1,863,763
Commercial Real Estate: Farmland and Commercial | Special Review |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 59,433 | 5,134
Commercial Real Estate: Farmland and Commercial | Watch List - Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 38,622 | 41,820
Commercial Real Estate: Farmland and Commercial | Watch List - Substandard |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 120,132 | 99,445
Commercial Real Estate: Farmland and Commercial | Watch - List Impaired |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 4,157 | 33,123
Commercial Real Estate: Multifamily |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 187,345 | 192,916
Commercial Real Estate: Multifamily | Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 185,823 | 192,440
Commercial Real Estate: Multifamily | Watch List - Substandard |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 936 |
Commercial Real Estate: Multifamily | Watch - List Impaired |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 586 | 476
Residential First Lien |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 426,546 | 432,777
Residential First Lien | Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 419,328 | 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 | 916 | 74
Residential First Lien | Watch - List Impaired |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 6,173 | 6,852
Residential Junior Lien |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 721,086 | 700,748
Residential Junior Lien | Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 719,464 | 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 | 882 |
Residential Junior Lien | Watch - List Impaired |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 740 | 723
Consumer |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 46,646 | 49,543
Consumer | Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 45,482 | 48,262
Consumer | Watch - List Impaired |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 1,164 | 1,281
Foreign |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 154,959 | 158,886
Foreign | Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 154,653 | 158,539
Foreign | Watch - List Impaired |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | $ 306 | $ 347

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