Summary of Property and Equipment (Detail) - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Property Plant And Equipment [Abstract]
Land and land improvements	$ 2,044	$ 1,990
Buildings and leasehold improvements	13,646	13,336
Furniture and equipment	2,319	2,217
Construction in progress	290	209
Property, Plant and Equipment, Gross, Total	18,299	17,752
Less accumulated depreciation and amortization	(7,638)	(7,177)
Property and equipment, net	$ 10,661	$ 10,575	$ 10,995