Interest Income and Interest Expense (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Interest income
Loans	$ 8,854	$ 7,947
Taxable securities	1,442	1,724
Non-taxable securities	443	398
Total securities	1,885	2,122
Trading assets	1,698	1,734
Federal funds sold and securities purchased under resale agreements	554	396
Securities borrowed	(92)	(120)
Deposits with banks	460	341
Other assets	193	145
Total interest income	13,552	12,565
Interest expense
Interest-bearing deposits	320	364
Federal funds purchased and securities loaned or sold under repurchase agreements	260	142
Commercial paper	33	34
Trading liabilities – debt, short-term and other liabilities	227	156
Long-term debt	1,219	1,094
Beneficial interests issued by consolidated VIEs	113	98
Total interest expense	2,172	1,888
Net interest income	11,380	10,677
Provision for credit losses	1,824	959
Net interest income after provision for credit losses	$ 9,556	$ 9,718