Restructuring and Other Charges, Net - Activity and Reserve Balances for Restructuring Charges (Detail) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2021	Dec. 31, 2020
Restructuring Cost and Reserve [Line Items]
Restructuring reserve beginning balance	$ 63	$ 137
Restructuring and other charges, net	6	52
Cash payments	(13)	(120)
Reversals and other		(6)
Restructuring reserve ending balance	56	63
Severance and Employee Termination Costs [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring reserve beginning balance	6	35
Restructuring and other charges, net		16
Cash payments	(2)	(41)
Reversals and other		(4)
Restructuring reserve ending balance	4	6
Other Costs [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring reserve beginning balance	57	102
Restructuring and other charges, net	6	36
Cash payments	(11)	(79)
Reversals and other		(2)
Restructuring reserve ending balance	$ 52	$ 57