GOODWILL AND INTANGIBLES - Schedule of Changes in the Carrying Amount of Goodwill by Reporting Segment (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2022
Goodwill [Roll Forward]
Balance at beginning of period	$ 854.7	$ 953.1
Impairment	0.0	(111.1)	$ 0.0
Acquisitions		3.0
Foreign currency impact	10.2	9.7
Balance at end of period	864.9	854.7	953.1
GPC
Goodwill [Roll Forward]
Balance at beginning of period	512.1	502.4
Impairment		0.0
Acquisitions		0.0
Foreign currency impact	10.2	9.7
Balance at end of period	522.3	512.1	502.4
H&G
Goodwill [Roll Forward]
Balance at beginning of period	342.6	342.6
Impairment		0.0
Acquisitions		0.0
Foreign currency impact	0.0	0.0
Balance at end of period	342.6	342.6	342.6
HPC
Goodwill [Roll Forward]
Balance at beginning of period	0.0	108.1
Impairment		(111.1)
Acquisitions		3.0
Foreign currency impact	0.0	0.0
Balance at end of period	$ 0.0	$ 0.0	$ 108.1