Accounts Payable And Other Current Liabilities (Schedule Of Accounts Payable And Other Current Liabilities) (Detail) (USD $) In Millions, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011
Accounts Payable And Accrued Liabilities Current And Noncurrent [Line Items]
Accounts payable	$ 360	$ 312
Accrued sales and use taxes	240	173
Accrued payroll and related	185	200
Public liability and property damage insurance liabilities - current	141	128
Income taxes payable - current	103	109
Deferred revenue	66	51
Advertising and marketing	87	77
Other	394	383
Accounts payable and other current liabilities	$ 1,576	$ 1,433