Quarterly Information (Detail) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Quarterly Financial Information Disclosure [Abstract]
Total revenue	$ 626	$ 526	$ 513	$ 491	$ 626	$ 552	$ 599	$ 545	$ 2,156	$ 2,322	$ 2,530
Gross profit	306	250	242	224	315	294	310	269
Operating (loss) income	59	7	(1)	(1)	98	89	87	(42)	64	232	(195)
Net (loss) income	$ (74)	$ 13	$ (4)	$ (2)	$ 58	$ 49	$ 64	$ (46)	$ (67)	$ 125	$ (214)
Net (loss) income per share:
Basic (in usd per share)	$ (0.61)	$ 0.11	$ (0.03)	$ (0.02)	$ 0.45	$ 0.38	$ 0.49	$ (0.36)	$ (0.53)	$ 0.96	$ (1.53)
Diluted (in usd per share)	$ (0.61)	$ 0.10	$ (0.03)	$ (0.02)	$ 0.44	$ 0.37	$ 0.49	$ (0.36)	$ (0.53)	$ 0.95	$ (1.53)
Impairment of goodwill, acquired intangibles and other assets								$ 76	$ 0	$ 80	$ 478
Impairment of goodwill								$ 57			$ 437
Tax Cuts and Jobs Act of 2017, existing income tax expense (benefit)	$ 126