Derivative Instruments - Gains (Losses) Recognized in Earnings for Other Economic Hedges and Customer-Related Positions (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2025	Mar. 31, 2024
Customer-Related Positions | Interest rate contracts | Purchased and written options
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) recognized in earnings	$ 12	$ (47)
Customer-Related Positions | Interest rate contracts | Futures
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) recognized in earnings	1	0
Customer-Related Positions | Swaps
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) recognized in earnings	35	131
Customer-Related Positions | Credit contracts
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) recognized in earnings	2	(1)
Customer-Related Positions | Foreign exchange rate contracts | Purchased and written options
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) recognized in earnings	1	0
Customer-Related Positions | Foreign exchange rate contracts | Forwards, spots and swaps
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) recognized in earnings	48	24
Customer-Related Positions | Commodity contracts | Purchased and written options
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) recognized in earnings	(1)	2
Customer-Related Positions | Commodity contracts | Futures
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) recognized in earnings	(41)	0
Customer-Related Positions | Commodity contracts | Swaps
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) recognized in earnings	47	2
Asset and Liability Management Positions | Other economic hedges | Interest rate contracts | Futures and forwards
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) recognized in earnings	24	(12)
Asset and Liability Management Positions | Other economic hedges | Interest rate contracts | Purchased and written options
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) recognized in earnings	30	39
Asset and Liability Management Positions | Other economic hedges | Swaps
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) recognized in earnings	56	(86)
Asset and Liability Management Positions | Other economic hedges | Foreign exchange forward contracts
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) recognized in earnings	2	4
Asset and Liability Management Positions | Other economic hedges | Equity contracts
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) recognized in earnings	(19)	0
Asset and Liability Management Positions | Other economic hedges | Credit contracts
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) recognized in earnings	17	(2)
Asset and Liability Management Positions | Other economic hedges | Other
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) recognized in earnings	$ 0	$ (75)