Summary of Significant Accounting Policies - Components of Property and Equipment (Detail) - USD ($) $ in Thousands		Oct. 31, 2020	Oct. 31, 2019
Property, Plant and Equipment, Net [Abstract]
Computer and other equipment		$ 788,105	$ 678,901
Buildings		129,746	68,708
Furniture and fixtures		72,702	72,437
Land		19,965	18,849
Leasehold improvements		242,830	273,985
Property and equipment gross		1,253,348	1,112,880
Less accumulated depreciation and amortization	[1]	(769,530)	(683,348)
Total		$ 483,818	$ 429,532

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