EARNINGS PER SHARE - Computation of Earnings Per Share Basic and Diluted (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jul. 31, 2021	Jul. 31, 2020	Jul. 31, 2021	Jul. 31, 2020
Numerator for basic and diluted EPS
Net income attributable to Greif, Inc.	$ 113.0	$ 20.7	$ 286.2	$ 64.4
Cash dividends	(26.2)	(26.2)	(78.4)	(78.2)
Undistributed earnings attributable to Greif, Inc.	$ 86.8	$ (5.5)	$ 207.8	$ (13.8)