Income Taxes (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Oct. 31, 2017	Oct. 31, 2016	Oct. 31, 2015
Operating Loss Carryforwards [Line Items]
DPT Prelim Notice of Assessment	$ 31.0
Effective tax rate (ETR)	5.30%	7.00%	(4.80%)
Statutory income tax rate	35.00%
Less valuation allowance	$ 59.1	$ 13.3
Undistributed earnings of its foreign subsidiaries	2,500.0
Research credit	0.7	$ 1.2	$ 0.7
Unrecognized tax benefits that would impact ETR	40.4
Interest and penalties	3.7
Unrecognized tax benefits related to tax positions	6.1
Federal [Member]
Operating Loss Carryforwards [Line Items]
Net operating loss carryforwards	31.8
Alternative minimum tax credits	7.0
Research credit	7.4
State and Local Jurisdiction [Member]
Operating Loss Carryforwards [Line Items]
Net operating loss carryforwards	43.7
California [Member]
Operating Loss Carryforwards [Line Items]
Research credit	$ 1.5