Derivative Financial Instruments - Notional Value of Derivative Contracts (Detail) - USD ($) $ in Millions	Sep. 30, 2024	Dec. 31, 2023
Derivative [Line Items]
Total	$ 1,371,460	$ 1,301,082
Interest rate contracts
Derivative [Line Items]
Total	130,294	122,702
Futures and forwards
Derivative [Line Items]
Total	28,547	5,143
Swaps
Derivative [Line Items]
Total	99,232	114,947
Options written
Derivative [Line Items]
Total	1,054	1,260
Options purchased
Derivative [Line Items]
Total	1,461	1,352
Foreign exchange contracts
Derivative [Line Items]
Total	1,177,384	1,096,967
Swaps, futures and forwards
Derivative [Line Items]
Total	1,040,911	1,005,683
Options written
Derivative [Line Items]
Total	39,030	30,755
Options purchased
Derivative [Line Items]
Total	39,115	30,898
Spot
Derivative [Line Items]
Total	58,328	29,631
Total commodities, equities and precious metals
Derivative [Line Items]
Total	43,309	63,287
Swaps, futures and forwards
Derivative [Line Items]
Total	32,824	53,110
Options written
Derivative [Line Items]
Total	1,570	1,713
Options purchased
Derivative [Line Items]
Total	8,915	8,464
Credit derivatives
Derivative [Line Items]
Total	19,021	16,710
Other Contracts
Derivative [Line Items]
Total	$ 1,452	$ 1,416