Stockholders' Equity (Schedule of Adjustments to Accumulated Other Comprehensive Income (Loss), Net) (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
Accumulated Other Comprehensive Income (Loss) [Line Items]
As of December 31, 2013			$ (4)
Other comprehensive income, before reclassifications			(20)
Amounts reclassified from accumulated other comprehensive income			(39)
Income tax (provision) benefit	(2)	(3)	10	(4)
As of June 30, 2014	(53)		(53)
Other Comprehensive Income (Loss), Net of Tax Portion Attributable To Equity Method Investee		1		1
Unrealized Gain (Loss) on Marketable Securities [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
As of December 31, 2013			0
Other comprehensive income, before reclassifications			0
Amounts reclassified from accumulated other comprehensive income			0
Income tax (provision) benefit			0
As of June 30, 2014	0		0
Foreign Currency Translation [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
As of December 31, 2013			(3)
Other comprehensive income, before reclassifications			(15)
Amounts reclassified from accumulated other comprehensive income			0
Income tax (provision) benefit			(2)
As of June 30, 2014	(20)		(20)
Gain (Loss) from Cash Flow Hedges [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
As of December 31, 2013			(44)
Other comprehensive income, before reclassifications			(5)
Amounts reclassified from accumulated other comprehensive income			2
Income tax (provision) benefit			(3)
As of June 30, 2014	(50)		(50)
Pension and Postretirement Benefits [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
As of December 31, 2013			43
Other comprehensive income, before reclassifications			0
Amounts reclassified from accumulated other comprehensive income			(41)
Income tax (provision) benefit			15
As of June 30, 2014	$ 17		$ 17