Consolidated Statements of Comprehensive Income (Loss) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Statement Of Income And Comprehensive Income [Abstract]
Net Income (Loss)	$ 53	$ 42	$ 128	$ (388)
Other Comprehensive (Loss) Income from Continuing Operations
Losses on treasury rate locks reclassified into income		1		1
Pension and other postretirement benefit plans	(3)	(1)	(2)	1
Other comprehensive (loss) income, before income taxes	(3)		(2)	2
Income tax (benefit) expense related to other comprehensive income	(1)		(1)	1
Other comprehensive (loss) income from continuing operations, net of income taxes	(2)		(1)	1
Other Comprehensive Income from Discontinued Operations, Net of Income Taxes		1		6
Comprehensive Income (Loss)	$ 51	$ 43	$ 127	$ (381)