Accumulated Other Comprehensive Income - Net Changes in Components of AOCI, Including Tax Effect (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Equity [Abstract]
Unrealized currency translation adjustments	$ 4.9	$ (3.7)	$ (5.2)	$ (1.1)
Defined benefit pension plans	(0.1)	0.0	0.2	0.0
Tax effect	0.1	0.0	0.0	0.0
Defined benefit pension plans, net of tax	0.0	0.0	0.2	0.0
Cash flow hedges	0.0	0.0	(0.1)	0.0
Tax effect	0.0	0.0	0.0	0.0
Cash flow hedges, net of tax	0.0	0.0	(0.1)	0.0
Total Other Comprehensive Income (Loss), net of tax	$ 4.9	$ (3.7)	$ (5.1)	$ (1.1)