ACQUISITIONS AND DIVESTITURES - Pro forma (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended	6 Months Ended
Apr. 30, 2024	Apr. 30, 2023	Apr. 30, 2024	Apr. 30, 2023
Lee Container Acquisition
Business Acquisition [Line Items]
Pro forma net sales		$ 1,326.2		$ 2,637.8
Pro forma net income attributable to Greif, Inc.		113.1		216.3
Ipackchem Acquisition
Business Acquisition [Line Items]
Pro forma net sales	$ 1,404.3	1,366.9	$ 2,665.7	2,693.4
Pro forma net income attributable to Greif, Inc.	$ 54.6	$ 114.9	$ 130.2	$ 190.2
Class A Common Stock \| Lee Container Acquisition
Business Acquisition [Line Items]
Basic earnings per share attributable to Greif, Inc. common shareholders: (in dollars per share)		$ 1.95		$ 3.73
Diluted earnings per share attributable to Greif, Inc. common shareholders: (in dollars per share)		1.93		3.70
Class A Common Stock \| Ipackchem Acquisition
Business Acquisition [Line Items]
Basic earnings per share attributable to Greif, Inc. common shareholders: (in dollars per share)	$ 0.94	3.28	$ 2.26	3.28
Diluted earnings per share attributable to Greif, Inc. common shareholders: (in dollars per share)	0.94	3.25	2.26	3.25
Class B Common Stock \| Lee Container Acquisition
Business Acquisition [Line Items]
Basic earnings per share attributable to Greif, Inc. common shareholders: (in dollars per share)		2.92		5.58
Diluted earnings per share attributable to Greif, Inc. common shareholders: (in dollars per share)		2.92		5.58
Class B Common Stock \| Ipackchem Acquisition
Business Acquisition [Line Items]
Basic earnings per share attributable to Greif, Inc. common shareholders: (in dollars per share)	1.42	4.90	3.38	4.90
Diluted earnings per share attributable to Greif, Inc. common shareholders: (in dollars per share)	$ 1.42	$ 4.90	$ 3.38	$ 4.90

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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