Stockholders' Equity - Schedule of Changes in Accumulated Other Comprehensive Income (Loss) Income (Details) - USD ($) $ in Millions	9 Months Ended	12 Months Ended
	Jul. 31, 2020	Oct. 31, 2018
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	$ 3,628.6
Gross change in value	(3.3)	$ (24.4)
Tax effect for the period	5.7	8.0
Ending balance	3,760.4	3,307.8
Foreign Currency Translation Adjustment
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(403.2)
Gross change in value	20.5	9.0
Tax effect for the period	0.0	0.0
Ending balance	(382.7)	(412.2)
Minimum Pension Liability
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(43.9)
Gross change in value	0.0	(33.4)
Tax effect for the period	0.0	8.0
Ending balance	(43.9)	(18.5)
Derivative Instruments
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	0.0
Gross change in value	(23.8)	0.0
Tax effect for the period	5.7	0.0
Ending balance	(18.1)	0.0
Accumulated Other Comprehensive Income (Loss)
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(447.1)
Ending balance	$ (444.7)	$ (430.7)