Restructuring Costs - Schedule of Accrued Restructuring Costs Activity (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Restructuring Reserve [Roll Forward]
Beginning balance	$ 22
Restructuring costs, net	2	$ 11
Payments	(9)
Ending balance	15
Employee severance and termination benefits
Restructuring Reserve [Roll Forward]
Beginning balance	10
Restructuring costs, net	1
Payments	(4)
Ending balance	7
Exited contractual commitments and other
Restructuring Reserve [Roll Forward]
Beginning balance	12
Restructuring costs, net	1
Payments	(5)
Ending balance	$ 8