Acquisitions - Schedule of Acquisition Related Expenses (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Business Acquisition [Line Items]
Business Combination, Acquisition Related Costs, Legal Fees	$ 4.0	$ 9.6	$ 2.1
Business Combination, Acquisition Related Costs, Employee Expense	1.1	5.1	0.2
Business Combination, Acquisition Related Costs, Technology and Contract Termination	6.6	10.2	0.2
Business Combination, Acquisition Related Costs, Other Expenses	0.7	2.3	0.3
Total acquisition related expenses	$ 12.4	$ 27.2	$ 2.8