CONDENSED CONSOLIDATED STATEMENTS OF CHANGES IN SHAREHOLDERS’ EQUITY (UNAUDITED) - USD ($) shares in Thousands, $ in Millions	Total	Executive	Directors	Capital Stock	Capital Stock Executive	Capital Stock Directors	Treasury Stock	Treasury Stock Executive	Treasury Stock Directors	Retained Earnings	Accumulated Other Comprehensive Income (Loss)	Greif, Inc. Equity	Greif, Inc. Equity Executive	Greif, Inc. Equity Directors	Non controlling interests
Beginning balance (shares) at Oct. 31, 2019				48,266			28,576
Beginning balance at Oct. 31, 2019	$ 1,191.1			$ 162.6			$ (134.8)			$ 1,539.0	$ (433.7)	$ 1,133.1			$ 58.0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	36.1									32.3		32.3			3.8
Other comprehensive income:
Foreign currency translation	(3.1)										(1.1)	(1.1)			(2.0)
Derivative financial instruments, net of income tax expense	0.2										0.2	0.2
Minimum pension liability adjustment, net of income tax expense	21.7										21.7	21.7
Comprehensive income	54.9											53.1
Current period mark to redemption value of redeemable noncontrolling interest	3.3									3.3		3.3
Net income allocated to redeemable noncontrolling interests	(0.1)														(0.1)
Dividends paid to Greif, Inc. shareholders	(25.9)									(25.9)		(25.9)
Dividends paid to noncontrolling interests and other	(0.8)														(0.8)
Restricted stock (shares)						3			(3)
Restricted stock			$ 0.2			$ 0.1			$ 0.1					$ 0.2
Ending balance (shares) at Jan. 31, 2020				48,269			28,573
Ending balance at Jan. 31, 2020	1,222.7			$ 162.7			$ (134.7)			1,548.7	(412.9)	1,163.8			58.9
Beginning balance (shares) at Oct. 31, 2020				48,450			28,392
Beginning balance at Oct. 31, 2020	1,200.7			$ 170.2			$ (134.4)			1,543.9	(427.5)	1,152.2			48.5
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	30.9									23.4		23.4			7.5
Other comprehensive income:
Foreign currency translation	27.6										25.0	25.0			2.6
Derivative financial instruments, net of income tax expense	1.9										1.9	1.9
Minimum pension liability adjustment, net of income tax expense	22.7										22.7	22.7
Comprehensive income	83.1											73.0
Current period mark to redemption value of redeemable noncontrolling interest	0.6									0.6		0.6
Net income allocated to redeemable noncontrolling interests	(0.3)														(0.3)
Dividends paid to Greif, Inc. shareholders	(25.9)									(25.9)		(25.9)
Dividends paid to noncontrolling interests and other	(1.0)														(1.0)
Long-term incentive shares issued (shares)				80			(80)
Long-term Incentive shares issued	4.1			$ 3.9			$ 0.2					4.1
Share based compensation	1.2			$ 1.2								1.2
Restricted stock (shares)					3			(3)
Restricted stock		$ 0.1			$ 0.1								$ 0.1
Ending balance (shares) at Jan. 31, 2021				48,533			28,309
Ending balance at Jan. 31, 2021	$ 1,262.6			$ 175.4			$ (134.2)			$ 1,542.0	$ (377.9)	$ 1,205.3			$ 57.3