Derivatives and Hedging Activities - Fair Value of Derivative Instruments (Details) € in Millions, $ in Millions	Mar. 31, 2021 USD ($)	Mar. 31, 2021 EUR (€)	Dec. 31, 2020 USD ($)
Derivatives not designated as hedging instruments:
Total Derivative Assets	$ 2.3		$ 7.3
Total Derivative Liabilities	(5.5)		(7.0)
Net Derivatives	(3.2)		0.3
Long-term debt, less current portion	3,706.6		3,731.4
Foreign currency forward and option contracts
Derivatives not designated as hedging instruments:
Total Derivative Assets	2.3		7.3
Total Derivative Liabilities	(5.5)		(7.0)
Designated as hedging instruments | Foreign currency forward and option contracts
Derivatives not designated as hedging instruments:
Long-term debt, less current portion	467.1	€ 400.0	490.2
Designated as hedging instruments | Cash Flow Hedge
Derivatives not designated as hedging instruments:
Total Derivative Assets	0.9		0.0
Total Derivative Liabilities	(1.2)		(2.8)
Net Derivatives	(0.3)		(2.8)
Designated as hedging instruments | Cash Flow Hedge | Foreign currency forward and option contracts
Derivatives not designated as hedging instruments:
Total Derivative Assets	0.9		0.0
Total Derivative Liabilities	(1.2)		(2.8)
Non-Designated as Hedging Instruments
Derivatives not designated as hedging instruments:
Total Derivative Assets	1.4		7.3
Total Derivative Liabilities	(4.3)		(4.2)
Net Derivatives	(2.9)		3.1
Non-Designated as Hedging Instruments | Foreign currency forward and option contracts
Derivatives not designated as hedging instruments:
Total Derivative Assets	1.4		7.3
Total Derivative Liabilities	$ (4.3)		$ (4.2)