Stockholders' Equity (Schedule of Adjustments to Accumulated Other Comprehensive Income (Loss), Net) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Accumulated Other Comprehensive Income (Loss), net [Line Items]
As of December 31, 2015	$ (348)
Other comprehensive income (loss) before reclassifications	70
Amounts reclassified from accumulated other comprehensive income (loss)	1
Income tax (provision) benefit	(6)	$ (10)
As of March 31, 2016	(283)
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	1
Amounts reclassified from accumulated other comprehensive income (loss)	0
Income tax (provision) benefit	0
As of March 31, 2016	2
Foreign Currency Translation [Member]
Accumulated Other Comprehensive Income (Loss), net [Line Items]
As of December 31, 2015	(339)
Other comprehensive income (loss) before reclassifications	70
Amounts reclassified from accumulated other comprehensive income (loss)	0
Income tax (provision) benefit	(6)
As of March 31, 2016	(275)
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	0
Amounts reclassified from accumulated other comprehensive income (loss)	0
Income tax (provision) benefit	0
As of March 31, 2016	(2)
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	(1)
Amounts reclassified from accumulated other comprehensive income (loss)	1
Income tax (provision) benefit	0
As of March 31, 2016	$ (8)