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Allowance for Probable Loan Losses (Portfolio Credit Quality By Loan Class) (Details) - USD ($) $ in Thousands | Mar. 31, 2016 | Dec. 31, 2015
--- | --- | ---
Loan portfolio by credit quality indicator |  |
Portfolio, total | $ 5,935,574 | $ 5,950,914
Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 5,534,164 | 5,529,707
Special Review |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 1,036 | 45,599
Watch List - Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 148,738 | 83,069
Watch List - Substandard |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 207,664 | 232,091
Watch - List Impaired |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 43,972 | 60,448
Commercial |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 946,175 | 966,852
Commercial | Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 770,631 | 771,999
Commercial | Special Review |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total |  | 42,152
Commercial | Watch List - Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 90,096 | 31,539
Commercial | Watch List - Substandard |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 70,590 | 90,215
Commercial | Watch - List Impaired |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 14,858 | 30,946
Commercial Real Estate: Other Construction and Land Development |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 1,708,152 | 1,649,827
Commercial Real Estate: Other Construction and Land Development | Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 1,641,268 | 1,582,683
Commercial Real Estate: Other Construction and Land Development | Special Review |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total |  | 1,164
Commercial Real Estate: Other Construction and Land Development | Watch List - Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 14,665 | 13,765
Commercial Real Estate: Other Construction and Land Development | Watch List - Substandard |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 46,254 | 45,994
Commercial Real Estate: Other Construction and Land Development | Watch - List Impaired |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 5,965 | 6,221
Commercial Real Estate: Farmland & Commercial |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 1,930,858 | 1,995,448
Commercial Real Estate: Farmland & Commercial | Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 1,786,473 | 1,849,587
Commercial Real Estate: Farmland & Commercial | Special Review |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 1,036 | 2,283
Commercial Real Estate: Farmland & Commercial | Watch List - Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 39,516 | 37,765
Commercial Real Estate: Farmland & Commercial | Watch List - Substandard |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 90,193 | 92,008
Commercial Real Estate: Farmland & Commercial | Watch - List Impaired |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 13,640 | 13,806
Commercial Real Estate: Multifamily |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 148,571 | 139,448
Commercial Real Estate: Multifamily | Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 147,841 | 138,546
Commercial Real Estate: Multifamily | Watch List - Substandard |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 566 | 125
Commercial Real Estate: Multifamily | Watch - List Impaired |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 164 | 777
Residential First Lien |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 412,340 | 410,244
Residential First Lien | Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 401,705 | 401,053
Residential First Lien | Watch List - Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 4,216 |
Residential First Lien | Watch List - Substandard |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 61 | 3,492
Residential First Lien | Watch - List Impaired |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 6,358 | 5,699
Residential Junior Lien |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 556,872 | 552,338
Residential Junior Lien | Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 555,595 | 551,138
Residential Junior Lien | Watch List - Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 245 |
Residential Junior Lien | Watch List - Substandard |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total |  | 250
Residential Junior Lien | Watch - List Impaired |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 1,032 | 950
Consumer |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 55,925 | 57,744
Consumer | Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 54,715 | 56,440
Consumer | Watch List - Substandard |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total |  | 7
Consumer | Watch - List Impaired |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 1,210 | 1,297
Foreign |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 176,681 | 179,013
Foreign | Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 175,936 | 178,261
Foreign | Watch - List Impaired |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | $ 745 | $ 752

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