Property, Plant and Equipment, net - Summary of Property, Plant and Equipment (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	$ 253	$ 265
Less: accumulated depreciation	(155)	(145)
Property, plant and equipment, net	98	120	$ 106
Information Technology Assets [Member]
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	49	46
Operating Equipment [Member]
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	101	109
Buildings and Land [Member]
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	102	100
Construction in Progress [Member]
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	$ 1	$ 10
Minimum [Member] | Information Technology Assets [Member]
Property Plant And Equipment [Line Items]
Property plant and equipment estimated useful lives	1 year
Minimum [Member] | Operating Equipment [Member]
Property Plant And Equipment [Line Items]
Property plant and equipment estimated useful lives	2 years
Minimum [Member] | Buildings [Member]
Property Plant And Equipment [Line Items]
Property plant and equipment estimated useful lives	5 years
Maximum [Member] | Information Technology Assets [Member]
Property Plant And Equipment [Line Items]
Property plant and equipment estimated useful lives	7 years
Maximum [Member] | Operating Equipment [Member]
Property Plant And Equipment [Line Items]
Property plant and equipment estimated useful lives	15 years
Maximum [Member] | Buildings [Member]
Property Plant And Equipment [Line Items]
Property plant and equipment estimated useful lives	35 years