Variable Interest Entities and Securitization Activities (Assets and Liabilities by Balance Sheet Caption) (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Assets
Cash and due from banks	$ 30,541	$ 24,816	$ 22,017
Restricted cash	35,356	34,231	33,979
Trading assets at fair value	266,299	298,282
Customer and other receivables	53,298	56,187
Goodwill	6,688	6,597	$ 6,577
Intangible assets	2,163	2,448
Other assets	15,641	16,628
Total assets	853,531	851,733
Liabilities
Other secured financings	5,245	3,863
Other liabilities and accrued expenses	17,204	17,157
Total liabilities	772,125	773,267
Noncontrolling interests	1,160	1,075
Consolidated VIEs
Assets
Cash and due from banks	77	69
Restricted cash	171	222
Trading assets at fair value	314	833
Customer and other receivables	25	19
Goodwill	18	18
Intangible assets	128	155
Other assets	402	485
Total assets	1,135	1,801
Liabilities
Other secured financings	64	438
Other liabilities and accrued expenses	22	25
Total liabilities	86	463
Noncontrolling interests	$ 106	$ 189