EXIT AND DISPOSAL ACTIVITIES - Schedule of Rollforward of Restructuring Accrual (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2024	Sep. 30, 2023
Restructuring Reserve [Roll Forward]
Accrual balance at beginning	$ 3.9	$ 4.0
Provisions	0.6	8.2
Cash expenditures	(3.2)	(8.4)
Non-cash items		0.1
Accrual balance at ending	1.3	3.9
Termination Benefits
Restructuring Reserve [Roll Forward]
Accrual balance at beginning	3.4	3.7
Provisions	0.6	7.6
Cash expenditures	(2.8)	(8.1)
Non-cash items		0.2
Accrual balance at ending	1.2	3.4
Other Costs
Restructuring Reserve [Roll Forward]
Accrual balance at beginning	0.5	0.3
Provisions	0.0	0.6
Cash expenditures	(0.4)	(0.3)
Non-cash items		(0.1)
Accrual balance at ending	$ 0.1	$ 0.5