Segment Information - Schedule of Segment Reporting Information, by Segment (Parenthetical) (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Segment Reporting Information [Line Items]
Interest expense	$ 136	$ 144	$ 272	$ 281
Operating Segments
Segment Reporting Information [Line Items]
Interest income	1		1	1
Interest expense	$ 4	$ 7	$ 8	$ 15