Derivative Financial Instruments - Net Gains (Losses) Recorded in the Consolidated Statements of Income Relating to Free-Standing Derivative Instruments Used For Customer Accommodation (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Derivative Instruments, Gain (Loss)
Net gains (losses) recorded in earnings	$ (103)	$ 46	$ (284)	$ (88)
Interest rate contracts | Contract revenue | Commercial banking revenue
Derivative Instruments, Gain (Loss)
Net gains (losses) recorded in earnings	10	12	26	19
Interest rate contracts | Credit portion of fair value adjustment | Other noninterest expense
Derivative Instruments, Gain (Loss)
Net gains (losses) recorded in earnings	3	1	9	16
Interest rate contracts | Interest rate lock commitments | Mortgage banking net revenue
Derivative Instruments, Gain (Loss)
Net gains (losses) recorded in earnings	11	57	11	89
Commodity contracts | Contract revenue | Commercial banking revenue
Derivative Instruments, Gain (Loss)
Net gains (losses) recorded in earnings	9	6	18	11
Commodity contracts | Credit portion of fair value adjustment | Other noninterest expense
Derivative Instruments, Gain (Loss)
Net gains (losses) recorded in earnings	(1)	(1)	(2)	0
Foreign exchange contracts | Other noninterest income
Derivative Instruments, Gain (Loss)
Net gains (losses) recorded in earnings	5	(3)	3	(5)
Foreign exchange contracts | Contract revenue | Commercial banking revenue
Derivative Instruments, Gain (Loss)
Net gains (losses) recorded in earnings	20	16	36	30
Foreign exchange contracts | Contract revenue | Other noninterest income
Derivative Instruments, Gain (Loss)
Net gains (losses) recorded in earnings	8	(2)	10	(1)
Foreign exchange contracts | Credit portion of fair value adjustment | Other noninterest expense
Derivative Instruments, Gain (Loss)
Net gains (losses) recorded in earnings	$ (2)	$ 0	$ (2)	$ 0