CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Millions	12 Months Ended
	Oct. 31, 2021	Oct. 31, 2020	Oct. 31, 2019
Statement of Comprehensive Income [Abstract]
Net income	$ 413.2	$ 124.3	$ 194.2
Other comprehensive income (loss), net of tax:
Foreign currency translation	(1.6)	(9.8)	(4.5)
Derivative financial instruments	21.1	(12.0)	(26.1)
Minimum pension liabilities	50.4	15.1	(25.3)
Other comprehensive income (loss), net of tax	69.9	(6.7)	(55.9)
Comprehensive income	483.1	117.6	138.3
Comprehensive income attributable to noncontrolling interests	21.4	2.6	23.9
Comprehensive income attributable to Greif, Inc.	$ 461.7	$ 115.0	$ 114.4