Asset Restructuring and Impairment Costs - Schedule of Restructuring and Impairment Charges (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2020	Jun. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Restructuring and Related Activities [Abstract]
Impairment losses	$ 0.0	$ 52.3	$ 0.0	$ 52.3	$ 0.0
Restructuring charges from idled assets	0.0		2.4	2.6	4.4
Severance costs	0.0	0.4	0.0	0.4	0.0
Total	$ 0.0	$ 55.3	$ 2.4	$ 55.3	$ 4.4

The aggregate amount of write-downs for impairments recognized during the period for long lived assets held for use (including those held for disposal by means other than sale).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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