Income Taxes - Components of Income Tax Expense/(Benefit) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Current income tax expense/(benefit)
U.S. federal	$ 3,160	$ 2,382	$ (654)
Non-U.S.	1,220	1,353	1,308
U.S. state and local	547	857	(4)
Total current income tax expense/(benefit)	4,927	4,592	650
Deferred income tax expense/(benefit)
U.S. federal	1,213	3,890	7,216
Non-U.S.	(95)	71	10
U.S. state and local	215	401	913
Total deferred income tax expense/(benefit)	1,333	4,362	8,139
Total income tax expense	6,260	8,954	8,789
Components of income tax expense/(benefit), supplemental information
Tax benefits recorded as a result of tax audit resolutions	2,400	451	531
Income tax effects allocated directly to equity	$ 1,500	$ (140)	$ 2,100