Accounts Payable And Other Current Liabilities (Schedule Of Accounts Payable And Other Current Liabilities) (Detail) (USD $) In Millions, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Payables and Accruals [Abstract]
Accounts payable	$ 344	$ 309
Accrued sales and use taxes	240	148
Accrued payroll and related	174	198
Public liability and property damage insurance liabilities - current	129	132
Deferred income - current	91	60
Advertising and marketing	87	82
Income taxes payable - current	54	58
Other	427	434
Accounts payable and other current liabilities	$ 1,546	$ 1,421