Segments and Entity-Wide Disclosures - Revenue, Profit (Loss) and Net Income (Loss) Reconciliation (Details) - USD ($) $ in Thousands	3 Months Ended
Jan. 31, 2020	Jan. 31, 2019
Revenue:
Total revenue	$ 832,912	$ 778,527
Less: Non-performance operating expenses
Selling and marketing	107,066	98,113
General and administrative	42,468	39,243
Amortization of intangible assets	5,853	5,528
Significant asset impairments and restructuring costs	4,472	2,273
Acquisition and integration costs	1,819	1,608
Add: Other non-performance financial items
Interest expense and other income, net	(5,169)	(5,188)
Loss on extinguishment and modification of debt	(646)	0
Less: Provision for income taxes	9,814	9,139
Net income	62,328	33,616
Networking Platforms
Revenue:
Total revenue	659,057	620,566
Platform Software and Services
Revenue:
Total revenue	51,888	41,598
Blue Planet Automation Software and Services
Revenue:
Total revenue	15,466	14,974
Global Services
Revenue:
Total revenue	106,501	101,389
Operating Segments
Revenue:
Total revenue	832,912	778,527
Add: Other non-performance financial items
Net income	239,635	194,708
Operating Segments \| Networking Platforms
Revenue:
Total revenue	659,057	620,566
Add: Other non-performance financial items
Net income	168,270	136,590
Operating Segments \| Platform Software and Services
Revenue:
Total revenue	51,888	41,598
Add: Other non-performance financial items
Net income	28,951	20,464
Operating Segments \| Blue Planet Automation Software and Services
Revenue:
Total revenue	15,466	14,974
Add: Other non-performance financial items
Net income	(3,113)	(2,047)
Operating Segments \| Global Services
Revenue:
Total revenue	106,501	101,389
Add: Other non-performance financial items
Net income	45,527	39,701
Converged Packet Optical
Revenue:
Total revenue	591,549	548,997
Converged Packet Optical \| Operating Segments \| Networking Platforms
Revenue:
Total revenue	591,549	548,997
Converged Packet Optical \| Operating Segments \| Platform Software and Services
Revenue:
Total revenue	0	0
Converged Packet Optical \| Operating Segments \| Blue Planet Automation Software and Services
Revenue:
Total revenue	0	0
Converged Packet Optical \| Operating Segments \| Global Services
Revenue:
Total revenue	0	0
Packet Networking
Revenue:
Total revenue	67,508	71,569
Packet Networking \| Operating Segments \| Networking Platforms
Revenue:
Total revenue	67,508	71,569
Packet Networking \| Operating Segments \| Platform Software and Services
Revenue:
Total revenue	0	0
Packet Networking \| Operating Segments \| Blue Planet Automation Software and Services
Revenue:
Total revenue	0	0
Packet Networking \| Operating Segments \| Global Services
Revenue:
Total revenue	0	0
Platform Software and Services
Revenue:
Total revenue	51,888	41,598
Platform Software and Services \| Operating Segments \| Networking Platforms
Revenue:
Total revenue	0	0
Platform Software and Services \| Operating Segments \| Platform Software and Services
Revenue:
Total revenue	51,888	41,598
Platform Software and Services \| Operating Segments \| Blue Planet Automation Software and Services
Revenue:
Total revenue	0	0
Platform Software and Services \| Operating Segments \| Global Services
Revenue:
Total revenue	0	0
Blue Planet Automation Software and Services
Revenue:
Total revenue	15,466	14,974
Blue Planet Automation Software and Services \| Operating Segments \| Networking Platforms
Revenue:
Total revenue	0	0
Blue Planet Automation Software and Services \| Operating Segments \| Platform Software and Services
Revenue:
Total revenue	0	0
Blue Planet Automation Software and Services \| Operating Segments \| Blue Planet Automation Software and Services
Revenue:
Total revenue	15,466	14,974
Blue Planet Automation Software and Services \| Operating Segments \| Global Services
Revenue:
Total revenue	0	0
Maintenance Support and Training
Revenue:
Total revenue	61,793	61,277
Maintenance Support and Training \| Operating Segments \| Networking Platforms
Revenue:
Total revenue	0	0
Maintenance Support and Training \| Operating Segments \| Platform Software and Services
Revenue:
Total revenue	0	0
Maintenance Support and Training \| Operating Segments \| Blue Planet Automation Software and Services
Revenue:
Total revenue	0	0
Maintenance Support and Training \| Operating Segments \| Global Services
Revenue:
Total revenue	61,793	61,277
Installation and Deployment
Revenue:
Total revenue	34,954	30,622
Installation and Deployment \| Operating Segments \| Networking Platforms
Revenue:
Total revenue	0	0
Installation and Deployment \| Operating Segments \| Platform Software and Services
Revenue:
Total revenue	0	0
Installation and Deployment \| Operating Segments \| Blue Planet Automation Software and Services
Revenue:
Total revenue	0	0
Installation and Deployment \| Operating Segments \| Global Services
Revenue:
Total revenue	34,954	30,622
Consulting and Network Design
Revenue:
Total revenue	9,754	9,490
Consulting and Network Design \| Operating Segments \| Networking Platforms
Revenue:
Total revenue	0	0
Consulting and Network Design \| Operating Segments \| Platform Software and Services
Revenue:
Total revenue	0	0
Consulting and Network Design \| Operating Segments \| Blue Planet Automation Software and Services
Revenue:
Total revenue	0	0
Consulting and Network Design \| Operating Segments \| Global Services
Revenue:
Total revenue	$ 9,754	$ 9,490

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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