Revenues and Long-Lived Assets by Geographical Area (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
Segment Reporting Information [Line Items]
Revenues	$ 1,348	$ 1,339
Property and equipment, net	10,382		$ 10,145
United States
Segment Reporting Information [Line Items]
Revenues	1,317	1,296
Property and equipment, net	10,233		9,913
Australia
Segment Reporting Information [Line Items]
Revenues	9	8
Property and equipment, net			85
Brazil
Segment Reporting Information [Line Items]
Revenues	5	7
Property and equipment, net	65		63
Canada
Segment Reporting Information [Line Items]
Revenues	10	10
Property and equipment, net	70		71
Chile
Segment Reporting Information [Line Items]
Revenues		5
Mexico
Segment Reporting Information [Line Items]
Revenues	7	7
Property and equipment, net	$ 14		$ 13
New Zealand
Segment Reporting Information [Line Items]
Revenues		$ 6