Leases (Lease Cost) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Operating lease cost
Fixed lease cost	$ 44.6	$ 44.0
Short-term lease cost	25.4	23.4
Variable lease cost	20.7	18.6
Finance lease cost
Amortization of leased assets	10.5	7.6
Interest on lease liabilities	9.3	8.2
Variable lease cost	16.4	14.0
Total lease cost	$ 126.9	$ 115.8