Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance			$ (338)	$ 24
Other comprehensive income (loss) before reclassifications, net of tax			(90)	(33)
Less: Amounts reclassified from AOCI, net of tax			(13)	18
Other comprehensive income (loss), net of tax	$ (43)	$ (41)	(77)	(51)
Ending balance	(415)	(27)	(415)	(27)
Derivatives
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance			16	35
Other comprehensive income (loss) before reclassifications, net of tax			(1)	1
Less: Amounts reclassified from AOCI, net of tax			(7)	4
Other comprehensive income (loss), net of tax			6	(3)
Ending balance	22	32	22	32
Defined Benefit Plans
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance			(302)	(32)
Other comprehensive income (loss) before reclassifications, net of tax			2	(6)
Less: Amounts reclassified from AOCI, net of tax			(6)	9
Other comprehensive income (loss), net of tax			8	(15)
Ending balance	(294)	(47)	(294)	(47)
Foreign Currency Translation
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance			(52)	21
Other comprehensive income (loss) before reclassifications, net of tax			(91)	(28)
Less: Amounts reclassified from AOCI, net of tax			0	5
Other comprehensive income (loss), net of tax			(91)	(33)
Ending balance	$ (143)	$ (12)	$ (143)	$ (12)