Noninterest Revenue and Noninterest Expense - Noninterest Expense (Details) - USD ($) $ in Millions	3 Months Ended			9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Jun. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Noninterest Income (Expense) [Abstract]
Legal expense	$ 62	$ 259		$ 301	$ 504
FDIC-related expense	258	312		549	1,576
Operating losses	301	397		1,001	1,019
Contribution of Visa shares	$ 0	$ 0	$ 1,000	0	1,000
FDIC special assessment accrual (release) increase				$ (437)	$ 725