Combined Summarized Operating Results for Affiliates (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Segment Reporting Revenue Reconciling Item [Line Items]
Total revenues	$ 617	$ 428	$ 381
Expenses	(473)	(346)	(294)
Depreciation and amortization	(112)	(56)	(46)
Operating profit	32	26	41
Interest expense	(59)	(43)	(43)
Gain on disposition	2
Net loss	$ (25)	$ (17)	$ (2)