Restructuring Activities - Components of Restructuring Accrual, Spending and Other Activity and Accrual Balance Remaining (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Restructuring Reserve [Roll Forward]
Restructuring accrual, beginning of period	$ 31.5	$ 37.5	$ 16.1
Accrual and accrual adjustments	11.0	41.9	47.8
Cash payments	(28.0)	(47.6)	(25.0)
Effect of changes in foreign currency exchange rates	(0.2)	(0.3)	(1.4)
Restructuring accrual, end of period	$ 14.3	$ 31.5	$ 37.5