EARNINGS PER SHARE - Computation of Earnings Per Share Basic and Diluted (Details) - USD ($) $ in Millions	3 Months Ended
Jan. 31, 2020	Jan. 31, 2019
Numerator for basic and diluted EPS
Net income attributable to Greif, Inc.	$ 32.3	$ 29.7
Cash dividends	(25.9)	(25.7)
Undistributed net income attributable to Greif, Inc.	$ 6.4	$ 4.0

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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