RESTRUCTURING CHARGES - Reconciliation of Beginning and Ending Restructuring Reserve Balances (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jul. 31, 2019	Jul. 31, 2018	Jul. 31, 2019	Jul. 31, 2018
Restructuring Reserve [Roll Forward]
October 31, 2018			$ 4.4
Costs incurred and charged to expense	$ 9.1	$ 3.7	20.3	$ 13.8
Costs paid or otherwise settled			(13.3)
July 31, 2019	11.4		11.4
Employee Separation Costs
Restructuring Reserve [Roll Forward]
October 31, 2018			4.2
Costs incurred and charged to expense	8.2		18.7
Costs paid or otherwise settled			(12.2)
July 31, 2019	10.7		10.7
Other Costs
Restructuring Reserve [Roll Forward]
October 31, 2018			0.2
Costs incurred and charged to expense	0.9		1.6
Costs paid or otherwise settled			(1.1)
July 31, 2019	$ 0.7		$ 0.7