Other Assets (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Other Assets [Abstract]
Securities borrowed	$ 26,643	$ 18,330
Derivative instruments, net	7,565	5,804
Bank-owned life insurance	3,548	3,479
Investments in joint ventures and other unconsolidated entities	3,140	3,095
Collateral, net	1,348	2,616
Receivable for securities settlement	621	117
Right-of-use assets	612	720
Prepaid expenses	474	383
Accounts receivable	395	379
Income tax receivable	359	367
Deferred tax assets, net of valuation allowance	196	233
Deposits with clearing organizations	62	58
Other Assets	988	929
Total	45,951	36,510
Advances	$ 532	$ 460