Interest and Other Income (Expense), Net (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Interest and Other Income (Expense), Net
Interest income	$ 3.2	$ 1.3	$ 1.2
Interest expense	(14.4)	(16.0)	(12.6)
Exchange gains (losses) on foreign currency transactions	(8.0)	(3.3)	(3.0)
Pension components	(3.3)	(2.5)	(3.9)
Other			0.6
Interest and other income (expense), net	$ (22.5)	$ (20.5)	$ (17.7)