Income Taxes - Schedule of Unrecognized Tax Benefits Roll Forward (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Beginning balance	$ 52.2	$ 38.7	$ 26.1
Additions for tax positions of prior periods	2.4	24.8	3.5
Additions for tax positions of the current period	6.9	4.2	9.0
Additions due to acquisitions	4.4	0.0	5.1
Reductions for tax positions of prior periods	(0.4)	(11.2)	(1.2)
Reductions attributable to settlements with taxing authorities	0.0	(1.5)	(0.6)
Reductions attributable to lapses of applicable statute of limitations	(1.9)	(2.8)	(3.2)
Ending balance	$ 63.6	$ 52.2	$ 38.7