Stock Compensation - Stock Compensation Expense (Detail) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Apr. 30, 2019	Apr. 30, 2018	Apr. 30, 2019	Apr. 30, 2018
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock compensation expense before taxes	$ 36,914	$ 32,965	$ 75,374	$ 65,288
Income tax benefit	(6,214)	(6,336)	(12,688)	(12,548)
Stock compensation expense after taxes	30,700	26,629	62,686	52,740
Cost of products
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock compensation expense before taxes	4,065	3,460	8,191	6,843
Cost of maintenance and service
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock compensation expense before taxes	1,522	1,290	2,981	2,537
Research and development expense
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock compensation expense before taxes	18,115	15,150	36,419	30,546
Sales and marketing expense
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock compensation expense before taxes	7,158	6,875	14,430	13,496
General and administrative expense
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock compensation expense before taxes	$ 6,054	$ 6,190	$ 13,353	$ 11,866

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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The amount of expense, net of income tax, recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

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