Restructuring - Additional Information (Detail) - USD ($) $ in Millions			3 Months Ended		6 Months Ended	9 Months Ended		38 Months Ended
	Jul. 29, 2020	Oct. 26, 2018	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2020	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2021
Restructuring Cost and Reserve [Line Items]
Restructuring charges			$ 23	$ (1)		$ 20	$ 58
2020 Restructuring Program
Restructuring Cost and Reserve [Line Items]
Restructuring charges			$ 23	$ 0		$ 23	$ 0
2020 Restructuring Program | Minimum
Restructuring Cost and Reserve [Line Items]
Restructuring expected cost	$ 25
2020 Restructuring Program | Maximum
Restructuring Cost and Reserve [Line Items]
Restructuring expected cost	35
2018 Restructuring Program | Minimum
Restructuring Cost and Reserve [Line Items]
Restructuring expected cost		$ 105
2018 Restructuring Program | Maximum
Restructuring Cost and Reserve [Line Items]
Restructuring expected cost		110
Real Estate | 2018 Restructuring Program
Restructuring Cost and Reserve [Line Items]
Restructuring expected cost		50
Employee Severance | 2018 Restructuring Program
Restructuring Cost and Reserve [Line Items]
Restructuring expected cost		60
Estimated Annual Savings | 2020 Restructuring Program | Minimum
Restructuring Cost and Reserve [Line Items]
Effect on future earnings, amount	5
Estimated Annual Savings | 2020 Restructuring Program | Maximum
Restructuring Cost and Reserve [Line Items]
Effect on future earnings, amount	$ 6
Estimated Annual Savings | 2018 Restructuring Program
Restructuring Cost and Reserve [Line Items]
Effect on future earnings, amount		$ 60
Forecast | 2020 Restructuring Program | Minimum
Restructuring Cost and Reserve [Line Items]
Restructuring charges					$ 25
Forecast | 2020 Restructuring Program | Maximum
Restructuring Cost and Reserve [Line Items]
Restructuring charges					$ 30
Forecast | Employee Severance | 2018 Restructuring Program
Restructuring Cost and Reserve [Line Items]
Payments for restructuring								$ 60