Acquisitions - Summary of Fair Values of Assets Acquired and Liabilities Assumed (Detail) - Sellers Affiliated with Blackstone and an Unrelated Third Party [Member] $ in Millions	Dec. 31, 2015 USD ($)
Business Acquisition [Line Items]
Property and equipment	$ 1,868
Intangibles	4
Cash and cash equivalents	16
Restricted cash	8
Prepaid expenses	3
Other assets	2
Accounts payable and accrued expenses	(25)
Debt	(450)
Net assets acquired	$ 1,426