Supplemental Condensed Consolidating Financial Information and Other Collateral-Related Information - Schedule of Quarterly Consolidated Financial Information (Parenthetical) (Detail) (USD $) In Millions, unless otherwise specified	1 Months Ended	3 Months Ended								12 Months Ended
	Mar. 31, 2013	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Stockholders Equity Excluding Portion Attributable To Subsidiaries Noncontrolling Interest [Abstract]
Losses (gains) on sales of facilities		$ 2	$ (1)	$ 3	$ (11)	$ 6	$ 5	$ (1)	$ (1)	$ (10)	$ 15	$ 142
Losses on retirement of debt	(17)				(11)					(17)		(481)
Legal claim costs						$ 110					$ 175