Supplemental Financial Statement Information - Schedule of Other Income, Net (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Other Income and Expenses [Abstract]
Rent and royalty income	$ 0.3	$ 0.3
Gains from disposal of property, plant and equipment, net	1.2	2.5
Net equity (loss) gain on joint ventures	0.0	(3.7)
Other income (expense), net	$ 1.5	(0.9)
Gain on the sale of oil and gas rights		$ 2.5

Rent, Royalty, And Other Income

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Amount of gain (loss) on sale or disposal of assets, including but not limited to property plant and equipment, intangible assets and equity in securities of subsidiaries or equity method investee.

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Amount of gain (loss) on sale or disposal of oil and gas property or timber property.

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Amount of income (loss) for proportionate share of equity method investee's income (loss).

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Amount of income (expense) related to nonoperating activities, classified as other.

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