Fair Value Measurements (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Fair value of assets and liabilities measured on recurring basis
Contingent consideration	$ (75.0)
Recurring basis
Fair value of assets and liabilities measured on recurring basis
Short-term investments	11.3	$ 17.4
Forward contracts	(2.4)	(1.3)
Contingent consideration	(75.0)	(75.0)
Total liability	(66.1)	(58.9)
Recurring basis | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair value of assets and liabilities measured on recurring basis
Short-term investments	11.3	17.4
Forward contracts	0.0	0.0
Contingent consideration	0.0	0.0
Total asset	11.3	17.4
Recurring basis | Significant Observable Inputs (Level 2)
Fair value of assets and liabilities measured on recurring basis
Short-term investments	0.0	0.0
Forward contracts	(2.4)	(1.3)
Contingent consideration	0.0	0.0
Total liability	(2.4)	(1.3)
Recurring basis | Significant Unobservable Inputs (Level 3)
Fair value of assets and liabilities measured on recurring basis
Short-term investments	0.0	0.0
Forward contracts	0.0	0.0
Contingent consideration	(75.0)	(75.0)
Total liability	$ (75.0)	$ (75.0)