Derivative Financial Instruments - Gains and Losses on Derivative Instruments Held For Other Purpose (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Derivatives, Fair Value [Line Items]
Gain (Loss) Recognized in Income on Derivatives	$ 224	$ (977)	$ 662	$ (1,442)
Gain (loss) on instruments designated at fair value and related derivatives
Derivatives, Fair Value [Line Items]
Gain (Loss) Recognized in Income on Derivatives	241	(963)	695	(1,445)
Gain (loss) on instruments designated at fair value and related derivatives | Interest rate contracts
Derivatives, Fair Value [Line Items]
Gain (Loss) Recognized in Income on Derivatives	(53)	(92)	(10)	(215)
Gain (loss) on instruments designated at fair value and related derivatives | Foreign exchange contracts
Derivatives, Fair Value [Line Items]
Gain (Loss) Recognized in Income on Derivatives	0	1	0	1
Gain (loss) on instruments designated at fair value and related derivatives | Equity contracts
Derivatives, Fair Value [Line Items]
Gain (Loss) Recognized in Income on Derivatives	294	(864)	706	(1,214)
Other income (loss) | Interest rate contracts
Derivatives, Fair Value [Line Items]
Gain (Loss) Recognized in Income on Derivatives	0	3	0	7
Other income (loss) | Credit contracts
Derivatives, Fair Value [Line Items]
Gain (Loss) Recognized in Income on Derivatives	(10)	5	(25)	10
Other income (loss) | Other Contracts
Derivatives, Fair Value [Line Items]
Gain (Loss) Recognized in Income on Derivatives	$ (7)	$ (30)	$ (9)	$ (31)