Restructuring - Summary of Liabilities Recognized Related to Restructuring Plan (Detail) - 2019 Restructuring Plan [Member] $ in Millions	3 Months Ended
	Mar. 31, 2021 USD ($)
Restructuring Cost And Reserve [Line Items]
Beginning Balance	$ 64.7
Expenses	19.0
Cash payments	(22.6)
Foreign currency exchange rate changes	(1.0)
Ending Balance	60.1
Expense incurred since the start of the 2019 Restructuring Plan	163.5
Expense estimated to be recognized for the 2019 Restructuring Plan	375.0
Employee Termination Benefits [Member]
Restructuring Cost And Reserve [Line Items]
Beginning Balance	38.7
Expenses	1.6
Cash payments	(6.5)
Foreign currency exchange rate changes	(1.0)
Ending Balance	32.8
Expense incurred since the start of the 2019 Restructuring Plan	80.1
Expense estimated to be recognized for the 2019 Restructuring Plan	200.0
Contract Termination [Member]
Restructuring Cost And Reserve [Line Items]
Beginning Balance	10.9
Expenses	5.3
Cash payments	(3.6)
Ending Balance	12.6
Expense incurred since the start of the 2019 Restructuring Plan	21.1
Expense estimated to be recognized for the 2019 Restructuring Plan	25.0
Other Restructuring [Member]
Restructuring Cost And Reserve [Line Items]
Beginning Balance	15.1
Expenses	12.1
Cash payments	(12.5)
Ending Balance	14.7
Expense incurred since the start of the 2019 Restructuring Plan	62.3
Expense estimated to be recognized for the 2019 Restructuring Plan	$ 150.0