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Allowance for Credit Losses (Portfolio Credit Quality By Loan Class) (Details) - USD ($) $ in Thousands | Sep. 30, 2020 | Dec. 31, 2019
--- | --- | ---
Loan portfolio by credit quality indicator |  |
Portfolio, total | $ 7,589,235 | $ 6,894,946
Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total |  | 6,538,085
Special Review |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total |  | 33,553
Watch List - Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total |  | 62,315
Watch List - Substandard |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total |  | 248,318
Watch - List Impaired |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total |  | 12,675
Commercial, financial and agricultural |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 4,426,866 | 3,379,837
Commercial, financial and agricultural | Domestic | Commercial |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 1,877,979 | 1,292,660
Commercial, financial and agricultural | Domestic | Commercial | Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 1,736,598 | 1,228,110
Commercial, financial and agricultural | Domestic | Commercial | Special Review |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 73,297 | 569
Commercial, financial and agricultural | Domestic | Commercial | Watch List - Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 65,664 | 39
Commercial, financial and agricultural | Domestic | Commercial | Watch List - Substandard |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 976 | 62,007
Commercial, financial and agricultural | Domestic | Commercial | Watch - List Impaired |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total |  | 1,935
Commercial, financial and agricultural | Domestic | Commercial Real Estate: farmland and commercial |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 2,110,950 | 1,896,747
Commercial, financial and agricultural | Domestic | Commercial Real Estate: farmland and commercial | Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 1,964,241 | 1,710,446
Commercial, financial and agricultural | Domestic | Commercial Real Estate: farmland and commercial | Special Review |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 9,567 | 13,184
Commercial, financial and agricultural | Domestic | Commercial Real Estate: farmland and commercial | Watch List - Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 71,162 | 20,183
Commercial, financial and agricultural | Domestic | Commercial Real Estate: farmland and commercial | Watch List - Substandard |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 65,479 | 151,726
Commercial, financial and agricultural | Domestic | Commercial Real Estate: farmland and commercial | Watch - List Impaired |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total |  | 1,208
Commercial, financial and agricultural | Domestic | Commercial Real Estate: multifamily |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 437,937 | 190,430
Commercial, financial and agricultural | Domestic | Commercial Real Estate: multifamily | Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 437,800 | 190,265
Commercial, financial and agricultural | Domestic | Commercial Real Estate: multifamily | Watch - List Impaired |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total |  | 165
Real estate - construction |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 1,943,430 | 2,185,883
Real estate - construction | Domestic | Commercial Real Estate: other construction and land development |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 1,943,430 | 2,185,883
Real estate - construction | Domestic | Commercial Real Estate: other construction and land development | Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 1,883,596 | 2,090,370
Real estate - construction | Domestic | Commercial Real Estate: other construction and land development | Special Review |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 12,625 | 18,721
Real estate - construction | Domestic | Commercial Real Estate: other construction and land development | Watch List - Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 27,529 | 41,949
Real estate - construction | Domestic | Commercial Real Estate: other construction and land development | Watch List - Substandard |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 18,769 | 33,905
Real estate - construction | Domestic | Commercial Real Estate: other construction and land development | Watch - List Impaired |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total |  | 938
Real estate - mortgage |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 1,033,646 | 1,140,377
Real estate - mortgage | Domestic | Residential First Lien |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 410,015 | 433,901
Real estate - mortgage | Domestic | Residential First Lien | Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 409,514 | 426,546
Real estate - mortgage | Domestic | Residential First Lien | Special Review |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total |  | 253
Real estate - mortgage | Domestic | Residential First Lien | Watch List - Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 146 | 144
Real estate - mortgage | Domestic | Residential First Lien | Watch List - Substandard |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 112 | 680
Real estate - mortgage | Domestic | Residential First Lien | Watch - List Impaired |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total |  | 6,278
Real estate - mortgage | Domestic | Residential Junior Lien |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 623,631 | 706,476
Real estate - mortgage | Domestic | Residential Junior Lien | Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 621,952 | 704,958
Real estate - mortgage | Domestic | Residential Junior Lien | Special Review |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 1,641 | 826
Real estate - mortgage | Domestic | Residential Junior Lien | Watch - List Impaired |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total |  | 692
Consumer |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 41,110 | 47,800
Consumer | Domestic |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 41,110 | 47,800
Consumer | Domestic | Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 41,107 | 46,605
Consumer | Domestic | Watch - List Impaired |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total |  | 1,195
Foreign |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 144,183 | 141,049
Foreign | Foreign |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 144,183 | 141,049
Foreign | Foreign | Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | $ 144,183 | 140,785
Foreign | Foreign | Watch - List Impaired |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total |  | $ 264

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