Derivative Financial Instruments - Gains and Losses on Derivative Instruments Designated and Qualifying As Hedging Instruments in Cash Flow Hedges (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in AOCI on Derivatives	$ 5	$ (385)	$ (65)
Gain (Loss) Reclassified From AOCI into Income	(174)	(43)	13
Foreign exchange contracts
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in AOCI on Derivatives	1	0	(1)
Foreign exchange contracts | Net interest income
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Reclassified From AOCI into Income	0	0	0
Interest rate contracts
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in AOCI on Derivatives	4	(385)	(64)
Interest rate contracts | Net interest income
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Reclassified From AOCI into Income	$ (174)	$ (43)	$ 13