Leases - Components of Lease Expense (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Leases [Abstract]
Fixed operating lease expense	$ 37.0	$ 39.6
Variable operating lease expense	6.9	6.0
Total operating lease expense	$ 43.9	$ 45.6