Summary of Significant Accounting Policies - Components of Property and Equipment (Detail) - USD ($) $ in Thousands	Oct. 31, 2017	Oct. 31, 2016
Property, Plant and Equipment, Net [Abstract]
Computer and other equipment	$ 540,257	$ 486,109
Buildings	68,877	68,194
Furniture and fixtures	54,882	51,589
Land	20,414	20,414
Leasehold improvements	153,619	136,773
Property and equipment gross	838,049	763,079
Less accumulated depreciation and amortization	(572,035)	(506,044)
Total	$ 266,014	$ 257,035