SEGMENT INFORMATION - Schedule of Depreciation and Amortization Relating to Segments (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2022
Segment Reporting, Other Significant Reconciling Item [Line Items]
Total depreciation and amortization	$ 101.8	$ 91.2	$ 99.3
Operating Segments
Segment Reporting, Other Significant Reconciling Item [Line Items]
Total depreciation and amortization	77.5	76.6	84.7
Operating Segments | GPC
Segment Reporting, Other Significant Reconciling Item [Line Items]
Total depreciation and amortization	36.7	37.4	37.4
Operating Segments | H&G
Segment Reporting, Other Significant Reconciling Item [Line Items]
Total depreciation and amortization	19.4	18.8	18.6
Operating Segments | HPC
Segment Reporting, Other Significant Reconciling Item [Line Items]
Total depreciation and amortization	21.4	20.4	28.7
Corporate and shared operations
Segment Reporting, Other Significant Reconciling Item [Line Items]
Total depreciation and amortization	$ 24.3	$ 14.6	$ 14.6