Interest Income and Interest Expense (Details) - USD ($) $ in Millions		3 Months Ended		9 Months Ended
		Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Interest income
Loans		$ 12,586	$ 12,207	$ 38,192	$ 34,915
Taxable securities		2,132	1,402	5,712	4,098
Non-taxable securities		318	394	1,021	1,199
Total investment securities		2,450	1,796	6,733	5,297
Trading assets - debt instruments		2,659	2,155	8,343	6,369
Federal funds sold and securities purchased under resale agreements		1,542	952	4,865	2,490
Securities borrowed		434	248	1,298	549
Deposits with banks		898	1,585	3,200	4,449
All other interest-earning assets		552	496	1,482	1,430
Total interest income	[1]	21,121	19,439	64,113	55,499
Interest expense
Interest-bearing deposits		2,409	1,621	7,010	4,021
Federal funds purchased and securities loaned or sold under repurchase agreements		1,241	827	3,577	2,164
Short-term borrowings		261	288	1,051	757
Trading liabilities – debt and all other interest-bearing liabilities		660	617	2,141	1,674
Long-term debt		2,188	2,056	6,796	5,812
Beneficial interest issued by consolidated VIEs		134	122	459	366
Total interest expense	[1]	6,893	5,531	21,034	14,794
Net interest income		14,228	13,908	43,079	40,705
Provision for credit losses		1,514	948	4,158	3,323
Net interest income after provision for credit losses		$ 12,714	$ 12,960	$ 38,921	$ 37,382

[1] In the second quarter of 2019, the Firm implemented certain presentation changes that impacted interest income and interest expense, but had no effect on net interest income. These changes were applied retrospectively and, accordingly, prior period amounts were revised to conform with the current presentation. Refer to Note 6 for additional information.