Summary of Property and Equipment (Detail) (USD $) In Millions, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Property Plant And Equipment [Line Items]
Land and land improvements	$ 1,948	$ 1,996
Buildings and leasehold improvements	13,478	13,665
Furniture and equipment	2,233	2,227
Construction in progress	178	199
Property, Plant and Equipment, Gross, Total	17,837	18,087
Less accumulated depreciation and amortization	(6,727)	(6,499)
Property and equipment, net	$ 11,110	$ 11,588