Restructuring - Additional Information (Detail) - USD ($) $ in Millions		3 Months Ended
	Oct. 26, 2018	Dec. 31, 2018	Dec. 31, 2019	Dec. 31, 2017
Restructuring Cost and Reserve [Line Items]
Remaining restructuring liability		$ 42	$ 24	$ 0
2018 Restructuring Program | Minimum
Restructuring Cost and Reserve [Line Items]
Effect on future earnings, amount	$ 60
Restructuring expected cost	105
2018 Restructuring Program | Maximum
Restructuring Cost and Reserve [Line Items]
Restructuring expected cost	110
Employee Termination Costs
Restructuring Cost and Reserve [Line Items]
Remaining restructuring liability		30	$ 21	$ 0
Employee Termination Costs | 2018 Restructuring Program | Minimum
Restructuring Cost and Reserve [Line Items]
Restructuring expected cost	$ 60
Real Estate | 2018 Restructuring Program | Maximum
Restructuring Cost and Reserve [Line Items]
Payments for restructuring		$ 50