ACQUISITIONS AND DIVESTITURES - Depreciation, Amortization, and Capital Expenditures from Discontinued Operations (Details) - Discontinued Operations, Held-for-Sale - Greif Containerboard Solutions, LLC - USD ($) $ in Millions	11 Months Ended	12 Months Ended
	Sep. 30, 2025	Oct. 31, 2024
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Depreciation and amortization	$ 24.2	$ 33.6
Capital expenditures	$ 50.0	$ 49.9