Stockholders' Equity (Schedule of Changes in Accumulated Other Comprehensive Income (Loss))(Details) - USD ($) $ in Millions	6 Months Ended	12 Months Ended
	Apr. 30, 2018	Oct. 31, 2017
Foreign Currency Translation Adjustment [Roll Forward]
Foreign Currency Translation Adjustment, Beginning Balance	$ (353.7)	$ (461.4)
Foreign Currency Translation Adjustment, Gross change in value for the period	59.3	107.7
Foreign Currency Translation Adjustment, Tax effect for the period		0.0
Foreign Currency Translation Adjustment, Ending Balance	(294.4)	(353.7)
Minimum Pension Liability [Roll Forward]
Minimum Pension Liability, Beginning Balance	(21.6)	(28.2)
Minimum Pension Liability, Gross change in value for the period	0.0	10.8
Minimum Pension Liability, Tax effect for the period		(4.2)
Minimum Pension Liability, Ending Balance	(21.6)	(21.6)
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Total, Beginning balance	(375.3)	(489.6)
Gross change in value for the period	59.3	118.5
Tax effect for the period		(4.2)
Total, Ending balance	$ (316.0)	$ (375.3)