Income Taxes - Additional Information (Detail) - USD ($)	3 Months Ended	12 Months Ended
	Jul. 31, 2018	Oct. 31, 2018	Oct. 31, 2017	Oct. 31, 2016
Operating Loss Carryforwards [Line Items]
Federal statutory rate		23.33%	35.00%	35.00%
Tax cuts and jobs act Of 2017 change in tax rate deferred tax asset (liabilities) income tax benefit	$ (69,300,000)
Change in tax rate deferred tax asset income tax expense		$ 72,000,000
Change in tax rate, income tax benefit	$ (35,900,000)
Provisional income tax expense (benefit)		52,800,000	$ 0	$ 0
Income (loss) before income tax expense		299,800,000	$ 200,300,000	$ 141,200,000
Increase (decrease) in valuation allowances		$ 24,800,000
Percentage of rate impact in valuation allowance		5.65%	20.74%	1.91%
Increase in effective tax rate				28.00%
Decrease in effective tax rate from foreign tax rates and permanent book-tax differences				15.90%
Net operating loss and other carryforwards		$ 122,800,000	$ 116,400,000
Valuation allowance		$ 157,200,000	132,400,000
Change in deferred tax assets valuation allowance, including tax act impact		11.66%
Unrecognized tax benefits		$ 36,200,000	26,800,000	$ 28,500,000
Accrued interest and penalties related to unrecognized tax benefits		4,900,000	3,700,000
Minimum
Operating Loss Carryforwards [Line Items]
Net decrease in unrecognized tax benefits for the next 12 months		0
Maximum
Operating Loss Carryforwards [Line Items]
Net decrease in unrecognized tax benefits for the next 12 months		3,000,000
Intercompany Financing
Operating Loss Carryforwards [Line Items]
Increase (decrease) in valuation allowances			$ 38,600,000
Percentage of rate impact in valuation allowance			19.26%
Non-U.S.
Operating Loss Carryforwards [Line Items]
Income (loss) before income tax expense		102,300,000	$ 85,200,000	49,900,000
Valuation allowance		137,100,000	127,300,000
Domestic Tax Authority
Operating Loss Carryforwards [Line Items]
Income (loss) before income tax expense		197,500,000	115,100,000	$ 91,300,000
Valuation allowance		$ 20,100,000	$ 5,100,000