Commitments and Guarantees - Contractual Amounts of Credit-Related Off-Balance Sheet Financial Instruments (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Commitments and Contingencies Disclosure [Abstract]
Unfunded credit facilities	$ 34,213	$ 29,697
Indemnified securities financing	440,875	367,901
Standby letters of credit	$ 3,330	$ 3,324
Unfunded commitments to extend credit, short term	73.00%
Term of unfunded commitment	1 year