Interest Income and Interest Expense (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Interest income
Loans	$ 12,880	$ 11,074
Taxable securities	1,705	1,313
Non-taxable securities	363	410
Total investment securities	2,068	1,723
Trading assets	2,769	2,103
Federal funds sold and securities purchased under resale agreements	1,647	731
Securities borrowed	356	62
Deposits with banks	1,170	1,321
All other interest-earning assets	1,004	681
Total interest income	21,894	17,695
Interest expense
Interest-bearing deposits	2,188	1,060
Federal funds purchased and securities loaned or sold under repurchase agreements	1,110	578
Short-term borrowings	427	209
Trading liabilities – debt and all other interest-bearing liabilities	1,224	660
Long-term debt	2,342	1,753
Beneficial interest issued by consolidated VIEs	150	123
Total interest expense	7,441	4,383
Net interest income	14,453	13,312
Provision for credit losses	1,495	1,165
Net interest income after provision for credit losses	$ 12,958	$ 12,147