Revenues and Long-Lived Assets by Geographical Area (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Segment Reporting Information [Line Items]
Revenues	$ 1,317	$ 1,309
Property and equipment, net	10,495		10,575
United States
Segment Reporting Information [Line Items]
Revenues	1,258	1,243
Property and equipment, net	10,089		10,111
Australia
Segment Reporting Information [Line Items]
Revenues	9	9
Property and equipment, net	95		102
Brazil
Segment Reporting Information [Line Items]
Revenues	7	7
Property and equipment, net	67		82
Canada
Segment Reporting Information [Line Items]
Revenues	14	19
Property and equipment, net	55		82
Chile
Segment Reporting Information [Line Items]
Revenues	7	9
Property and equipment, net	43		44
Mexico
Segment Reporting Information [Line Items]
Revenues	7	7
Property and equipment, net	24		26
New Zealand
Segment Reporting Information [Line Items]
Revenues	15	15
Property and equipment, net	$ 122		$ 128