Restructuring and Other Charges - Schedule of Change in Restructuring Reserves (Details) $ in Millions	3 Months Ended
	Dec. 31, 2020 USD ($)
Restructuring Reserve [Roll Forward]
Beginning balance	$ 10.0
Restructuring charges	4.5
Utilized - cash	(7.1)
Utilized - noncash	(2.3)
Foreign currency translation	0.1
Ending balance	5.2
Employee Severance and Termination Benefits
Restructuring Reserve [Roll Forward]
Beginning balance	9.7
Restructuring charges	0.2
Utilized - cash	(5.7)
Foreign currency translation	0.1
Ending balance	4.3
Property, Plant and Equipment Impairment
Restructuring Reserve [Roll Forward]
Restructuring charges	2.3
Utilized - noncash	(2.3)
Other Costs
Restructuring Reserve [Roll Forward]
Beginning balance	0.3
Restructuring charges	2.0
Utilized - cash	(1.4)
Ending balance	$ 0.9