Stockholders' Equity (Schedule of Adjustments to Accumulated Other Comprehensive Income (Loss), Net) (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), net [Line Items]
As of December 31, 2014			$ (165)
Other comprehensive income (loss) before reclassifications			(126)
Amounts reclassified from accumulated other comprehensive income (loss)			5
Income tax (provision) benefit	$ (3)	$ 14	(6)	$ 24
As of September 30, 2015	(292)		(292)
Unrealized Gain (Loss) on Marketable Securities [Member]
Accumulated Other Comprehensive Income (Loss), net [Line Items]
As of December 31, 2014			1
Other comprehensive income (loss) before reclassifications			1
Amounts reclassified from accumulated other comprehensive income (loss)			0
Income tax (provision) benefit			(1)
As of September 30, 2015	1		1
Foreign Currency Translation [Member]
Accumulated Other Comprehensive Income (Loss), net [Line Items]
As of December 31, 2014			(151)
Other comprehensive income (loss) before reclassifications			(125)
Amounts reclassified from accumulated other comprehensive income (loss)			0
Income tax (provision) benefit			(5)
As of September 30, 2015	(281)		(281)
Gain (Loss) from Cash Flow Hedges [Member]
Accumulated Other Comprehensive Income (Loss), net [Line Items]
As of December 31, 2014			(4)
Other comprehensive income (loss) before reclassifications			(2)
Amounts reclassified from accumulated other comprehensive income (loss)			5
Income tax (provision) benefit			(1)
As of September 30, 2015	(2)		(2)
Pension and Postretirement Benefits [Member]
Accumulated Other Comprehensive Income (Loss), net [Line Items]
As of December 31, 2014			(11)
Other comprehensive income (loss) before reclassifications			0
Amounts reclassified from accumulated other comprehensive income (loss)			0
Income tax (provision) benefit			1
As of September 30, 2015	$ (10)		$ (10)