Income Taxes - Unrecognized Tax Benefts (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Unrecognized tax benefits, beginning balance	$ 38.7	$ 47.7	$ 28.2
Increase in prior year tax positions	0.2	5.6	1.5
Decrease in prior year tax positions	(3.1)	(16.9)	(0.4)
Increase in current year tax positions	4.4	6.0	10.5
Increase from acquisitions			8.3
Settlement		(3.7)	(1.2)
Foreign currency remeasurement adjustment	0.9		0.8
Unrecognized tax benefits, ending balance	41.1	38.7	47.7
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued [Abstract]
Unrecognized tax benefits, interest and penalties, beginning balance	6.9	7.5	2.5
Increase in prior year tax positions	4.5	3.5	3.1
Decrease in prior year tax positions	(0.1)	(2.5)	0.0
Increase in current year tax positions	0.0	0.0	0.0
Increase from acquisitions			1.9
Settlement		(1.6)	(0.1)
Foreign currency remeasurement adjustment	0.2		0.1
Unrecognized tax benefits, interest and penalties, ending balance	$ 11.5	$ 6.9	$ 7.5