Restructuring, Reserve (Details) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
2020 Restructuring Program
Restructuring Reserve [Roll Forward]
Restructuring Reserve, Beginning Balance	$ 1.6	$ 1.2
Charge to Income	1.4	4.0
Cash	1.6	3.3
Non-Cash	0.0	0.0
Restructuring Reserve, Ending Balance	1.4	1.9
2019 Restructuring Program
Restructuring Reserve [Roll Forward]
Restructuring Reserve, Beginning Balance	4.1	8.2
Charge to Income	3.9	6.6
Cash	6.0	8.7
Non-Cash	1.2	1.4
Restructuring Reserve, Ending Balance	0.8	4.7
Severance & termination related costs | 2020 Restructuring Program
Restructuring Reserve [Roll Forward]
Restructuring Reserve, Beginning Balance	0.9	0.4
Charge to Income	0.3	0.3
Cash	0.2	0.0
Non-Cash	0.0	0.0
Restructuring Reserve, Ending Balance	1.0	0.7
Severance & termination related costs | 2019 Restructuring Program
Restructuring Reserve [Roll Forward]
Restructuring Reserve, Beginning Balance	1.4	5.3
Charge to Income	(0.1)	0.1
Cash	1.0	3.4
Non-Cash	0.0	0.0
Restructuring Reserve, Ending Balance	0.3	2.0
Accelerated depreciation & asset write-offs | 2019 Restructuring Program
Restructuring Reserve [Roll Forward]
Restructuring Reserve, Beginning Balance	0.0	0.0
Charge to Income	1.2	1.4
Cash	0.0	0.0
Non-Cash	1.2	1.4
Restructuring Reserve, Ending Balance	0.0	0.0
Other exit costs | 2020 Restructuring Program
Restructuring Reserve [Roll Forward]
Restructuring Reserve, Beginning Balance	0.7	0.8
Charge to Income	1.1	3.7
Cash	1.4	3.3
Non-Cash	0.0	0.0
Restructuring Reserve, Ending Balance	0.4	1.2
Other exit costs | 2019 Restructuring Program
Restructuring Reserve [Roll Forward]
Restructuring Reserve, Beginning Balance	2.2	2.9
Charge to Income	2.8	5.1
Cash	4.5	5.3
Non-Cash	0.0	0.0
Restructuring Reserve, Ending Balance	0.5	$ 2.7
Net gain on sale of fixed assets | 2019 Restructuring Program
Restructuring Reserve [Roll Forward]
Restructuring Reserve, Beginning Balance	0.5
Charge to Income	0.0
Cash	0.5
Non-Cash	0.0
Restructuring Reserve, Ending Balance	$ 0.0