CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) (UNAUDITED) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jul. 31, 2020	Jul. 31, 2019	Jul. 31, 2020	Jul. 31, 2019
Statement of Comprehensive Income [Abstract]
Net income	$ 24.4	$ 67.5	$ 76.3	$ 124.4
Other comprehensive income (loss), net of tax:
Foreign currency translation	59.6	(0.9)	4.2	(10.4)
Derivative financial instruments	2.0	(5.0)	(20.9)	(20.7)
Minimum pension liabilities	(2.4)	2.3	20.6	2.2
Other comprehensive income (loss), net of tax	59.2	(3.6)	3.9	(28.9)
Comprehensive income	83.6	63.9	80.2	95.5
Comprehensive income attributable to noncontrolling interests	0.9	6.1	3.5	18.7
Comprehensive income attributable to Greif, Inc.	$ 82.7	$ 57.8	$ 76.7	$ 76.8