Summary of Long-Term Debt and Maturities (Detail) - USD ($) $ in Millions	Sep. 30, 2017	Dec. 31, 2016
Debt Instrument [Line Items]
Total long-term debt	$ 2,579	$ 2,188
Less: current maturities of long-term debt	12	12
deferred financing costs, net	31	29
Total long-term debt, net	2,536	2,147
Senior Secured Credit Facility Term B-3 Loan, variable due 2022
Debt Instrument [Line Items]
Total long-term debt	1,179	1,188
5.0% Senior Notes due 2024
Debt Instrument [Line Items]
Total long-term debt	1,000	$ 1,000
4.75% Senior Notes due 2027
Debt Instrument [Line Items]
Total long-term debt	400
deferred financing costs, net	$ 5