Leases - Sublease Income (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Lessee, Lease, Description [Line Items]
Operating lease expense	$ 20.0	$ 27.2	$ 28.3
Lease income	(3.7)	(1.7)	(1.0)
Total operating lease expense, net	16.3	25.5	27.3
Amortization of right-of-use assets	3.0	3.5	3.6
Interest on lease liabilities	0.3	0.5	0.7
Total finance lease expense	3.3	4.0	4.3
Total costs of products/services sold	3,843.9	1,600.5	2,544.9
Operations and maintenance	121.0	131.8	138.8
General and administrative	97.6	91.5	103.4
Short-term lease cost	2.2	5.5	3.7
Operating Leases
Lessee, Lease, Description [Line Items]
Total costs of products/services sold	13.4	17.6	17.5
Operations and maintenance	3.9	6.7	8.0
General and administrative	$ 2.7	$ 2.9	$ 2.8