Supplemental Financial Statement Information - Other Non-operating Income (Expense) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Disaggregation of Revenue [Line Items]
Rent, royalty income and other income	$ 1.1	$ 0.9	$ 2.9
Gains from disposal of property, plant and equipment, net	2.9	2.9	90.7
Income (loss) from equity method investments	0.1	(7.0)	(10.7)
Gain (loss) on sale of businesses, net	13.8	0.0	(7.1)
Joint venture restructuring and impairment charges	0.0	(2.4)	(11.4)
Other	0.3	0.1	0.0
Other income (loss), net	18.2	(1.2)	64.4
Gain from sale of certain oil and gas rights			91.7
Gain on asset sales and sale of business, net	13.8	2.5	84.6
Buyer of Formerly-Owned Business
Disaggregation of Revenue [Line Items]
Revisions of estimates	$ 0.0	$ 4.3	$ 0.0

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