Changes in Other Comprehensive Income (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013	Mar. 31, 2014	Dec. 31, 2013	Mar. 31, 2013	Dec. 31, 2012
Changes in Other Comprehensive Income [Abstract]
Accumulated Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Net of Tax	$ (24)	$ (29)	$ (24)	$ (29)	$ (22)	$ (16)	$ (23)	$ (26)
Accumulated Other Comprehensive Income (Loss), Cumulative Changes in Net Gain (Loss) from Cash Flow Hedges, Effect Net of Tax	86	152	86	152	114	141	109	34
Accumulated Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Net of Tax	(20)	(41)	(20)	(41)	(20)	(19)	(41)	(41)
Accumulated Other Comprehensive Income (Loss), Net of Tax	42	82	42	82	72	106	45	(33)
Cumulative Translation Adjustment, Net of Tax, Period Increase (Decrease)	(2)	(6)	(8)	(3)
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Before Reclassifications, Net of Tax	(13)	47	(27)	118
Other Comprehensive (Income) Loss, Pension and Other Postretirement Benefit Plans, Adjustment, before Reclassification Adjustments, Net of Tax	0	0	(1)	0
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax	(15)	41	(36)	115
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Reclassified from OCI, Net of Tax	(15)	(4)	(28)	0
Other Comprehensive Income (Loss), Reclassifications out of OCI, Net of Tax	(15)	(4)	(28)	0
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax	(2)	(6)	(8)	(3)
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Net of Tax	(28)	43	(55)	118
Net change in certain retirement plans	0	0	(1)	0
Other Comprehensive Income (Loss), Net of Tax	(30)	37	(64)	115
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Tax	7	26	13	71
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising Reclassed from OCI, Tax	$ 8	$ 2	$ 16	$ 0