Stockholders' Equity (Schedule of Adjustments to Accumulated Other Comprehensive Income (Loss), Net) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Accumulated Other Comprehensive Income (Loss), net [Line Items]
As of December 31, 2015			$ (348)
Other comprehensive income (loss) before reclassifications			52
Amounts reclassified from accumulated other comprehensive income (loss)			(1)
Income tax (provision) benefit	$ (6)	$ (3)	(13)	$ (6)
As of September 30, 2016	(310)		(310)
Unrealized Gain (Loss) on Marketable Securities [Member]
Accumulated Other Comprehensive Income (Loss), net [Line Items]
As of December 31, 2015			1
Other comprehensive income (loss) before reclassifications			0
Amounts reclassified from accumulated other comprehensive income (loss)			0
Income tax (provision) benefit			0
As of September 30, 2016	1		1
Foreign Currency Translation [Member]
Accumulated Other Comprehensive Income (Loss), net [Line Items]
As of December 31, 2015			(339)
Other comprehensive income (loss) before reclassifications			51
Amounts reclassified from accumulated other comprehensive income (loss)			0
Income tax (provision) benefit			(13)
As of September 30, 2016	(301)		(301)
Gain (Loss) from Cash Flow Hedges [Member]
Accumulated Other Comprehensive Income (Loss), net [Line Items]
As of December 31, 2015			(2)
Other comprehensive income (loss) before reclassifications			1
Amounts reclassified from accumulated other comprehensive income (loss)			0
Income tax (provision) benefit			0
As of September 30, 2016	(1)		(1)
Pension and Postretirement Benefits [Member]
Accumulated Other Comprehensive Income (Loss), net [Line Items]
As of December 31, 2015			(8)
Other comprehensive income (loss) before reclassifications			0
Amounts reclassified from accumulated other comprehensive income (loss)			(1)
Income tax (provision) benefit			0
As of September 30, 2016	$ (9)		$ (9)