Restructuring Activities - Summary of Changes in Liabilities for Restructuring Activities (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Restructuring And Related Activities [Abstract]
Beginning Balance	$ 38	$ 72	$ 99
Charges	105	51	89
Non cash charges and other adjustments	(1)	(8)	(3)
Payments	(69)	(77)	(113)
Ending Balance	$ 73	$ 38	$ 72