Derivatives and Hedging Activities - Schedule of Pre-Tax Net Gains (Losses) on Derivatives Not Designated as Hedging Instruments (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Derivative Instruments, Gain (Loss) [Line Items]
Total net gains (losses)	$ 67	$ 21
Interest rate
Derivative Instruments, Gain (Loss) [Line Items]
Total net gains (losses)	8	14
Foreign exchange
Derivative Instruments, Gain (Loss) [Line Items]
Total net gains (losses)	13	12
Commodity
Derivative Instruments, Gain (Loss) [Line Items]
Total net gains (losses)	2	2
Credit
Derivative Instruments, Gain (Loss) [Line Items]
Total net gains (losses)	(8)	(12)
Other
Derivative Instruments, Gain (Loss) [Line Items]
Total net gains (losses)	52	5
Corporate services income
Derivative Instruments, Gain (Loss) [Line Items]
Total net gains (losses)	23	22
Corporate services income \| Interest rate
Derivative Instruments, Gain (Loss) [Line Items]
Total net gains (losses)	8	8
Corporate services income \| Foreign exchange
Derivative Instruments, Gain (Loss) [Line Items]
Total net gains (losses)	13	12
Corporate services income \| Commodity
Derivative Instruments, Gain (Loss) [Line Items]
Total net gains (losses)	2	2
Corporate services income \| Credit
Derivative Instruments, Gain (Loss) [Line Items]
Total net gains (losses)	0	0
Corporate services income \| Other
Derivative Instruments, Gain (Loss) [Line Items]
Total net gains (losses)	0	0
Consumer mortgage income
Derivative Instruments, Gain (Loss) [Line Items]
Total net gains (losses)	2	0
Consumer mortgage income \| Interest rate
Derivative Instruments, Gain (Loss) [Line Items]
Total net gains (losses)	0	0
Consumer mortgage income \| Foreign exchange
Derivative Instruments, Gain (Loss) [Line Items]
Total net gains (losses)	0	0
Consumer mortgage income \| Commodity
Derivative Instruments, Gain (Loss) [Line Items]
Total net gains (losses)	0	0
Consumer mortgage income \| Credit
Derivative Instruments, Gain (Loss) [Line Items]
Total net gains (losses)	0	0
Consumer mortgage income \| Other
Derivative Instruments, Gain (Loss) [Line Items]
Total net gains (losses)	2	0
Other income
Derivative Instruments, Gain (Loss) [Line Items]
Total net gains (losses)	42	(1)
Other income \| Interest rate
Derivative Instruments, Gain (Loss) [Line Items]
Total net gains (losses)	0	6
Other income \| Foreign exchange
Derivative Instruments, Gain (Loss) [Line Items]
Total net gains (losses)	0	0
Other income \| Commodity
Derivative Instruments, Gain (Loss) [Line Items]
Total net gains (losses)	0	0
Other income \| Credit
Derivative Instruments, Gain (Loss) [Line Items]
Total net gains (losses)	(8)	(12)
Other income \| Other
Derivative Instruments, Gain (Loss) [Line Items]
Total net gains (losses)	$ 50	$ 5