Noninterest Revenue and Noninterest Expense - Card Income (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Disaggregation of Revenue [Line Items]
Total card income	$ 1,234	$ 975
Interchange and merchant processing income
Disaggregation of Revenue [Line Items]
Total card income	7,139	6,235
Rewards costs and partner payments
Disaggregation of Revenue [Line Items]
Total card income	(5,509)	(4,870)
Other card income
Disaggregation of Revenue [Line Items]
Total card income	$ (396)	$ (390)