Goodwill and Other Intangible Assets - Goodwill Business Segments (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Goodwill [Roll Forward]
Goodwill, beginning balance	$ 14,777	$ 14,782	$ 14,653
Acquisitions	273		130
Other adjustments	15	(5)	(1)
Goodwill, ending balance	15,065	14,777	14,782
Credit Card
Goodwill [Roll Forward]
Goodwill, beginning balance	5,078	5,087	5,088
Acquisitions	273		0
Other adjustments	15	(9)	(1)
Goodwill, ending balance	5,366	5,078	5,087
Consumer Banking
Goodwill [Roll Forward]
Goodwill, beginning balance	4,645	4,645	4,645
Acquisitions	0		0
Other adjustments	0	0	0
Goodwill, ending balance	4,645	4,645	4,645
Commercial Banking
Goodwill [Roll Forward]
Goodwill, beginning balance	5,054	5,050	4,920
Acquisitions	0		130
Other adjustments	0	4	0
Goodwill, ending balance	$ 5,054	$ 5,054	$ 5,050