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Restructuring and Other Charges - Schedule of Change in Restructuring Reserves (Details) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Sep. 30, 2020	Jun. 30, 2020	Sep. 30, 2020
Restructuring Reserve [Roll Forward]
Restructuring charges	$ 13.0	$ 10.2	$ 14.4
Utilized - cash			(3.5)
Utilized - noncash			(0.8)
Foreign currency translation			(0.1)
Ending balance	10.0		10.0
Employee Severance and Termination Benefits
Restructuring Reserve [Roll Forward]
Restructuring charges			13.3
Utilized - cash			(3.5)
Foreign currency translation			(0.1)
Ending balance	9.7		9.7
Property, Plant and Equipment Impairment
Restructuring Reserve [Roll Forward]
Restructuring charges			0.8
Utilized - noncash			(0.8)
Other Costs
Restructuring Reserve [Roll Forward]
Restructuring charges			0.3
Ending balance	$ 0.3		$ 0.3