Segment and Entity Wide Disclosures - Customer Concentration (Details) - USD ($) $ in Thousands	12 Months Ended
	Oct. 31, 2019	Oct. 31, 2018	Oct. 31, 2017
Revenue, Major Customer [Line Items]
Revenues	$ 3,572,131	$ 3,094,286	$ 2,801,687
Revenue
Revenue, Major Customer [Line Items]
Percent of revenue	59.30%	56.50%	55.60%
Customer Concentration Risk | Revenue
Revenue, Major Customer [Line Items]
Revenues	$ 1,219,068	$ 692,589	$ 736,991
Customer Concentration Risk | Revenue | Verizon
Revenue, Major Customer [Line Items]
Revenues	459,787	318,013	288,048
Customer Concentration Risk | Revenue | AT&T
Revenue, Major Customer [Line Items]
Revenues	388,704	$ 374,576	$ 448,943
Customer Concentration Risk | Revenue | Web-scale provider
Revenue, Major Customer [Line Items]
Revenues	$ 370,577