Segments and Entity-Wide Disclosures (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jul. 31, 2018	Jul. 31, 2017	Jul. 31, 2018	Jul. 31, 2017	Oct. 31, 2017
Segment Reporting Information [Line Items]
Equipment, building, furniture and fixtures, net	$ 295,863		$ 295,863		$ 308,465
Maintenance spares, net	43,700		43,700
Net revenue	818,817	$ 728,719	2,194,930	$ 2,057,238
United States
Segment Reporting Information [Line Items]
Equipment, building, furniture and fixtures, net	79,243		79,243		$ 90,482
Net revenue	469,200	$ 438,100	1,245,300	$ 1,209,800
India
Segment Reporting Information [Line Items]
Net revenue	83,600
Networking Platforms
Segment Reporting Information [Line Items]
Other intangible assets, net	32,100		32,100
Software and Software-Related Services
Segment Reporting Information [Line Items]
Other intangible assets, net	$ 76,200		$ 76,200