Components of Lease Expense (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Leases [Abstract]
Operating lease expense	$ 24.0	$ 20.6
Amortization of Right-of-Use Assets	0.3	0.1
Finance Lease, Interest Expense	0.1	0.1
Variable lease expense	$ 1.8	$ 3.2