Segment Information - Schedule of Segment Reporting Information, by Segment (Parenthetical) (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Segment Reporting Information [Line Items]
Interest expense	$ 138	$ 160	$ 419	$ 462
Operating Segments
Segment Reporting Information [Line Items]
Interest income		1	1	6
Interest expense	$ 7	$ 9	$ 22	$ 29