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Allowance for Probable Loan Losses (Portfolio Credit Quality By Loan Class) (Details) - USD ($) $ in Thousands | Mar. 31, 2019 | Dec. 31, 2018
--- | --- | ---
Loan portfolio by credit quality indicator |  |
Portfolio, total | $ 6,707,343 | $ 6,561,289
Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 6,316,834 | 6,126,933
Special Review |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 63,671 | 64,135
Watch List - Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 52,626 | 92,976
Watch List - Substandard |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 218,163 | 253,345
Watch - List Impaired |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 56,049 | 23,900
Commercial |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 1,213,539 | 1,128,969
Commercial | Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 1,130,988 | 998,625
Commercial | Special Review |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 19 | 441
Commercial | Watch List - Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 3,061 | 44,544
Commercial | Watch List - Substandard |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 60,863 | 76,180
Commercial | Watch - List Impaired |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 18,608 | 9,179
Commercial Real Estate:Other Construction and Land Development |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 1,934,346 | 1,886,231
Commercial Real Estate:Other Construction and Land Development | Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 1,865,359 | 1,817,098
Commercial Real Estate:Other Construction and Land Development | Special Review |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 1,640 | 1,648
Commercial Real Estate:Other Construction and Land Development | Watch List - Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 9,284 | 9,055
Commercial Real Estate:Other Construction and Land Development | Watch List - Substandard |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 56,004 | 56,338
Commercial Real Estate:Other Construction and Land Development | Watch - List Impaired |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 2,059 | 2,092
Commercial Real Estate: Farmland and Commercial |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 1,896,658 | 1,949,898
Commercial Real Estate: Farmland and Commercial | Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 1,669,873 | 1,726,711
Commercial Real Estate: Farmland and Commercial | Special Review |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 62,012 | 62,046
Commercial Real Estate: Farmland and Commercial | Watch List - Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 39,269 | 38,373
Commercial Real Estate: Farmland and Commercial | Watch List - Substandard |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 99,113 | 119,259
Commercial Real Estate: Farmland and Commercial | Watch - List Impaired |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 26,391 | 3,509
Commercial Real Estate: Multifamily |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 294,112 | 226,257
Commercial Real Estate: Multifamily | Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 292,687 | 224,823
Commercial Real Estate: Multifamily | Watch List - Substandard |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 918 | 927
Commercial Real Estate: Multifamily | Watch - List Impaired |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 507 | 507
Residential First Lien |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 456,914 | 445,800
Residential First Lien | Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 449,291 | 438,773
Residential First Lien | Watch List - Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 142 | 142
Residential First Lien | Watch List - Substandard |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 1,265 | 641
Residential First Lien | Watch - List Impaired |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 6,216 | 6,244
Residential Junior Lien |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 721,112 | 727,301
Residential Junior Lien | Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 719,334 | 725,538
Residential Junior Lien | Watch List - Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 870 | 862
Residential Junior Lien | Watch - List Impaired |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 908 | 901
Consumer |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 46,073 | 46,316
Consumer | Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 44,999 | 45,141
Consumer | Watch - List Impaired |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 1,074 | 1,175
Foreign |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 144,589 | 150,517
Foreign | Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 144,303 | 150,224
Foreign | Watch - List Impaired |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | $ 286 | $ 293

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