Summary of Significant Accounting Policies - Components of Property and Equipment (Detail) - USD ($) $ in Thousands		Oct. 31, 2021	Oct. 31, 2020
Property, Plant and Equipment, Net [Abstract]
Computer and other equipment		$ 812,161	$ 788,105
Buildings		134,931	129,746
Furniture and fixtures		73,624	72,702
Land		19,965	19,965
Leasehold improvements		236,064	242,830
Property and equipment gross		1,276,745	1,253,348
Less accumulated depreciation and amortization	[1]	(804,347)	(769,530)
Total		$ 472,398	$ 483,818

[1] Accumulated depreciation and amortization includes write-offs due to retirement of fully amortized fixed assets.