Other assets impairments, restructuring and other items - Schedule of Other Assets Impairments, Restructuring and Other Items (Detail) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2021	Mar. 31, 2020
Restructuring and Impairment Costs [Line Items]
Impairments of long-lived tangible assets	[1]	$ 48	$ 75
Contingent consideration		3	6
Restructuring		81	39
Other		4
Total		$ 137	$ 121

[1] Including impairments related to exit and disposal activities