Derivative Financial Instruments - Gains and Losses on Derivative Instruments Held For Other Purpose (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Derivatives, Fair Value [Line Items]
Gain (Loss) Recognized in Income on Derivatives	$ (395)	$ (73)	$ (1,837)	$ 729
Gain (loss) on instruments designated at fair value and related derivatives
Derivatives, Fair Value [Line Items]
Gain (Loss) Recognized in Income on Derivatives	(402)	(80)	(1,847)	719
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	(103)	(8)	(318)	(62)
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	0	1	0
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	(293)	(62)	(1,507)	810
Other income (loss) | Interest rate contracts
Derivatives, Fair Value [Line Items]
Gain (Loss) Recognized in Income on Derivatives	0	(1)	7	(2)
Other income (loss) | Credit contracts
Derivatives, Fair Value [Line Items]
Gain (Loss) Recognized in Income on Derivatives	(3)	(5)	7	(17)
Other income (loss) | Other Contracts
Derivatives, Fair Value [Line Items]
Gain (Loss) Recognized in Income on Derivatives	$ 4	$ 3	$ (27)	$ 0