Segments and Entity-Wide Disclosures (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jul. 31, 2019	Jul. 31, 2018	Jul. 31, 2019	Jul. 31, 2018	Oct. 31, 2018
Segment Reporting Information [Line Items]
Equipment, building, furniture and fixtures, net	$ 280,630		$ 280,630		$ 292,067
Goodwill	297,884		297,884		297,968
Maintenance spares, net	51,100		51,100
Net revenue	960,606	$ 818,817	2,604,144	$ 2,194,930
United States
Segment Reporting Information [Line Items]
Equipment, building, furniture and fixtures, net	62,231		62,231		$ 75,479
Net revenue	592,200	469,200	1,600,000	$ 1,250,000
India
Segment Reporting Information [Line Items]
Net revenue		$ 83,600
Networking Platforms
Segment Reporting Information [Line Items]
Intangible assets, net	22,700		22,700
Goodwill	65,700		65,700
Software and Software-Related Services
Segment Reporting Information [Line Items]
Intangible assets, net	98,600		98,600
Goodwill	$ 232,200		$ 232,200