Schedule of Accounts Payable and Other Current Liabilities (Detail) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Accounts Payable and Other Current Liabilities [Abstract]
Accounts payable	$ 371	$ 359
Accrued sales and use taxes	208	218
Employee-related Liabilities, Current	200	176
Accrued marketing and commissions, current	192	190
Public liability and property damage insurance liabilities – current	149	145
Deferred revenue – current	140	135
Accrued insurance	91	103
Other	342	293
Accounts payable and other current liabilities	$ 1,693	$ 1,619