Supplementary Information - Interest and Other Income (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Segment Reporting [Abstract]
Earnings of equity method investments	$ 91	$ 45	$ 89
Interest income	33	41	60
Unrealized gain on marketable securities	39
Interest and other income, net	$ 163	$ 86	$ 149