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Business Segments (Operating Results and Other Key Financial Measures) (Details) - USD ($) $ in Thousands | 3 Months Ended |
--- | --- | ---
Mar. 31, 2018 | Mar. 31, 2017 | Dec. 31, 2017
Segment Reporting Information |  |  |
Interest income | $ 371,873 | $ 302,669 |
Charge for funds used | (178,966) | (120,414) |
Interest spread on funds used | 192,907 | 182,255 |
Interest expense | (45,180) | (30,547) |
Credit on funds provided | 178,966 | 120,414 |
Interest spread on funds provided (used) | 133,786 | 89,867 |
Net interest income before provision for credit losses | 326,693 | 272,122 |
Provision for credit losses | 20,218 | 7,068 |
Noninterest income | 74,444 | 115,828 |
Noninterest expense | 169,135 | 152,878 |
Segment income (loss) before income taxes | 211,784 | 228,004 |
Segment income after income taxes | 187,032 | 169,736 |
Segment assets | 37,693,158 | 35,342,126 | $ 37,150,249
Retail Banking |  |  |
Segment Reporting Information |  |  |
Interest income | 104,710 | 81,025 |
Charge for funds used | (49,273) | (27,738) |
Interest spread on funds used | 55,437 | 53,287 |
Interest expense | (24,940) | (16,183) |
Credit on funds provided | 145,451 | 102,546 |
Interest spread on funds provided (used) | 120,511 | 86,363 |
Net interest income before provision for credit losses | 175,948 | 139,650 |
Provision for credit losses | 3,093 | 378 |
Noninterest income | 44,448 | 13,564 |
Noninterest expense | 81,968 | 72,844 |
Segment income (loss) before income taxes | 135,335 | 79,992 |
Segment income after income taxes | 96,968 | 47,035 |
Segment assets | 9,345,892 | 8,213,268 |
Commercial Banking |  |  |
Segment Reporting Information |  |  |
Interest income | 239,577 | 192,419 |
Charge for funds used | (111,366) | (64,509) |
Interest spread on funds used | 128,211 | 127,910 |
Interest expense | (9,179) | (5,098) |
Credit on funds provided | 25,448 | 12,043 |
Interest spread on funds provided (used) | 16,269 | 6,945 |
Net interest income before provision for credit losses | 144,480 | 134,855 |
Provision for credit losses | 17,125 | 6,690 |
Noninterest income | 27,438 | 25,734 |
Noninterest expense | 65,020 | 54,373 |
Segment income (loss) before income taxes | 89,773 | 99,526 |
Segment income after income taxes | 64,362 | 58,796 |
Segment assets | 21,992,393 | 19,624,237 |
Other |  |  |
Segment Reporting Information |  |  |
Interest income | 27,586 | 29,225 |
Charge for funds used | (18,327) | (28,167) |
Interest spread on funds used | 9,259 | 1,058 |
Interest expense | (11,061) | (9,266) |
Credit on funds provided | 8,067 | 5,825 |
Interest spread on funds provided (used) | (2,994) | (3,441) |
Net interest income before provision for credit losses | 6,265 | (2,383) |
Provision for credit losses | 0 | 0 |
Noninterest income | 2,558 | 76,530 |
Noninterest expense | 22,147 | 25,661 |
Segment income (loss) before income taxes | (13,324) | 48,486 |
Segment income after income taxes | 25,702 | 63,905 |
Segment assets | $ 6,354,873 | $ 7,504,621 |

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