Commitments and Contingencies - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended				3 Months Ended	12 Months Ended			12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2012 City of San Francisco	Dec. 31, 2012 Litigation Related to Other Taxes	Dec. 31, 2012 Litigation Related to Other Taxes	Dec. 31, 2012 Litigation Related to Other Taxes Excise Tax Related Liabilities	Dec. 31, 2012 Litigation Related to Other Taxes Accrued Interest	Dec. 31, 2012 Litigation relating to occupancy tax	Dec. 31, 2011 Litigation relating to occupancy tax	Dec. 31, 2010 Litigation relating to occupancy tax	Dec. 31, 2009 Litigation relating to occupancy tax	Dec. 31, 2012 Matters relating to hotel booking practices
Loss Contingencies [Line Items]
Lease rental expense	$ 70	$ 67	$ 48
Lease obligations, latest maturity year	2021
Number of lawsuits filed by cities, counties and states involving hotel occupancy taxes									80
Number of lawsuits currently active									43
Number of lawsuits dismissed to date									32
Number of dismissals based on finding that defendant was not subject to local hotel occupancy tax or the local government lacked standing to pursue claims									19
Reserve for potential settlement of issues related to hotel occupancy taxes									35	32
Accrual related to court decisions and final settlements related to hotel occupancy taxes										10
Occupancy tax assessments tax payment (refund)										(3)	3	48
Tax assessments including interest and penalties				22
Litigation relating to general excise tax, court ruled amount					110	110	78	32
Litigation related to general excise tax, possible penalty percentage					50.00%	50.00%
Litigation relating to general excise tax, accrual					110	110
Estimate of possible penalties and additional assessment for 2012 and other items						$ 60
Number of Putative class action law suits													32