Derivatives and Hedging Activities (Details 2) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Derivative Instruments, Gain (Loss) [Line Items]
Pretax gains (losses)		$ 293
Not Designated as Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Pretax gains (losses)	$ 21	364
Other Expense [Member] | Foreign exchange contracts [Member] | Not Designated as Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Pretax gains (losses)	$ 13	$ 365