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Business Segment Information - Amounts of Consolidated Revenue, Expense, Tax and Assets by Segment (Details) - USD ($) $ in Millions | 3 Months Ended
--- | ---
Mar. 31, 2024 | Mar. 31, 2023
Disaggregation of Revenue [Line Items] |  |
Net interest income (expense) | $ 625 | $ 688
Provision for credit losses | 50 | 50
Noninterest income | 194 | 171
Noninterest expense | 515 | 478
Income (loss) before income taxes | 254 | 331
Income tax expense (benefit) | 57 | 76
Net income | 197 | 255
Average assets | 81,243 | 78,841
Regional Banking |  |
Disaggregation of Revenue [Line Items] |  |
Net interest income (expense) | 532 | 561
Provision for credit losses | 28 | 37
Noninterest income | 105 | 104
Noninterest expense | 324 | 313
Income (loss) before income taxes | 285 | 315
Income tax expense (benefit) | 67 | 74
Net income | 218 | 241
Average assets | 43,131 | 41,292
Specialty Banking |  |
Disaggregation of Revenue [Line Items] |  |
Net interest income (expense) | 153 | 151
Provision for credit losses | 23 | 14
Noninterest income | 72 | 56
Noninterest expense | 104 | 100
Income (loss) before income taxes | 98 | 93
Income tax expense (benefit) | 24 | 23
Net income | 74 | 70
Average assets | 23,712 | 22,623
Corporate |  |
Disaggregation of Revenue [Line Items] |  |
Net interest income (expense) | (60) | (24)
Provision for credit losses | (1) | (1)
Noninterest income | 17 | 11
Noninterest expense | 87 | 65
Income (loss) before income taxes | (129) | (77)
Income tax expense (benefit) | (34) | (21)
Net income | (95) | (56)
Average assets | 14,400 | 14,926
Restructuring costs | 5 |
Special assessment fee | $ 10 |
Corporate | TD Transaction |  |
Disaggregation of Revenue [Line Items] |  |
Merger and integration expense |  | $ 21

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