Goodwill and Other Intangible Assets - Components (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Goodwill
Carrying Amount of Assets	$ 15,065	$ 14,777
Net Carrying Amount	15,065	14,777	$ 14,782	$ 14,653
Other intangible assets:
Carrying Amount of Assets	540	342
Accumulated Amortization	(230)	(183)
Net Carrying Amount	310	159
Total goodwill and other intangible assets
Carrying Amount of Assets	15,605	15,119
Net Carrying Amount	15,375	14,936
Commercial MSRs
Carrying Amount of Assets	653	660
Accumulated Amortization	(263)	(223)
Net Carrying Amount	$ 390	$ 437
Weighted Average Remaining Amortization Period	6 years 10 months 24 days	7 years 3 months 18 days
Amortization expense for amortizable intangible assets	$ 88	$ 93
Purchased credit card relationship (“PCCR”) intangibles
Other intangible assets:
Carrying Amount of Assets	369	147
Accumulated Amortization	(96)	(26)
Net Carrying Amount	$ 273	$ 121
Commercial MSRs
Weighted Average Remaining Amortization Period	7 years 1 month 6 days	7 years 9 months 18 days
Other
Other intangible assets:
Carrying Amount of Assets	$ 171	$ 195
Accumulated Amortization	(134)	(157)
Net Carrying Amount	$ 37	$ 38
Commercial MSRs
Weighted Average Remaining Amortization Period	5 years 8 months 12 days	5 years 4 months 24 days