Leases - Components of Lease Expenses (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Leases [Abstract]
Amortization of right-of-use assets	$ 4.4	$ 4.2	$ 4.1
Interest on lease liabilities	3.3	3.4	3.5
Operating lease cost	35.6	35.7	36.5
Variable lease cost	3.3	3.2	2.9
Short-term lease cost	0.5	0.4	1.2
Net lease cost	$ 47.1	$ 46.9	$ 48.2