DIVESTITURES - Schedule of Components of Income from Discontinued Operations, Net of Tax (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2022
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Income from discontinued operations, net of tax	$ 25.5	$ 2,035.6	$ 149.7
Income from discontinued operations, net of tax attributable to noncontrolling interest	0.0	0.3	0.9
Income from discontinued operations, net of tax attributable to controlling interest	25.5	2,035.3	148.8
Discontinued Operations, Held-for-sale or Disposed of by Sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Income from discontinued operations before income taxes	25.1	2,909.3	203.1
Income tax (benefit) expense from discontinued operations	(0.4)	873.7	53.4
Income from discontinued operations, net of tax	25.5	2,035.6	149.7
Income from discontinued operations, net of tax attributable to noncontrolling interest	0.0	0.3	0.9
Income from discontinued operations, net of tax attributable to controlling interest	25.5	2,035.3	148.8
Discontinued Operations, Held-for-sale or Disposed of by Sale | HHI Segment
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Income from discontinued operations before income taxes	14.9	136.9	253.3
Gain on sale of discontinued operations before income taxes	0.0	2,824.2	0.0
Discontinued Operations, Held-for-sale or Disposed of by Sale | Other Disposal Group
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Income from discontinued operations before income taxes	10.2	(2.4)	(3.8)
Discontinued Operations, Held-for-sale or Disposed of by Sale | Corporate Debt
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Income from discontinued operations before income taxes	$ 0.0	$ 49.4	$ 46.4