CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Statement Of Income And Comprehensive Income [Abstract]
Net Income (Loss)	$ 42	$ 62	$ (388)	$ 130
Other Comprehensive Income from Continuing Operations
Loss on treasury rate locks reclassified into income	1		1
Pension and other postretirement benefit plans	(1)	(6)	1	(5)
Other comprehensive (loss) income, before income taxes		(6)	2	(5)
Income tax expense (benefit) related to other comprehensive income		(4)	1	(3)
Other comprehensive (loss) income from continuing operations, net of income taxes		(2)	1	(2)
Other Comprehensive Income from Discontinued Operations, Net of Income Taxes	1	6	6	14
Comprehensive Income (Loss)	$ 43	$ 66	$ (381)	$ 142