Other Assets (Details) - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
Other Assets [Abstract]
Securities borrowed	$ 24,773	$ 18,330
Derivative instruments, net	8,170	5,804
Bank-owned life insurance	3,502	3,479
Investments in joint ventures and other unconsolidated entities	3,027	3,095
Collateral, net	1,639	2,713
Receivable for securities settlement	1,110	117
Right-of-use assets	632	720
Accounts receivable	468	379
Prepaid expenses	461	383
Income tax receivable	300	367
Deferred tax assets, net of valuation allowance	221	233
Deposits with clearing organizations	58	58
Other	872	832
Total	$ 45,233	$ 36,510