Ciena Corporation and Significant Accounting Policies and Estimates (Details) - USD ($) $ in Thousands	12 Months Ended
	Oct. 31, 2019	Nov. 01, 2018	Oct. 31, 2018	Nov. 01, 2017
Significant Accounting Policies [Line Items]
Cost method investments	$ 10,727		$ 8,056
Expected economic lives of finite-lived intangible assets (in years)	7 years
Expected number of years Spares usage cost is expensed	4 years
Cumulative amount of temporary differences for unremitted foreign earnings for which a deferred tax liability has not been recognized	$ 372,000
Cumulative-effect adjustment		$ 49,805		$ 62,123
One-time employee termination benefits related to service period (in days)	60 days
Minimum
Significant Accounting Policies [Line Items]
Payment terms and cash received	30 days
Maximum
Significant Accounting Policies [Line Items]
Payment terms and cash received	90 days
Foreign exchange contract maturities	24 months
Equipment, furniture and fixtures | Minimum
Significant Accounting Policies [Line Items]
Estimated useful lives capitalized and amortized straight-line (in years)	2 years
Equipment, furniture and fixtures | Maximum
Significant Accounting Policies [Line Items]
Estimated useful lives capitalized and amortized straight-line (in years)	5 years
Software and website development | Minimum
Significant Accounting Policies [Line Items]
Estimated useful lives capitalized and amortized straight-line (in years)	2 years
Software and website development | Maximum
Significant Accounting Policies [Line Items]
Estimated useful lives capitalized and amortized straight-line (in years)	5 years
3.75% Convertible Senior Notes due October 15, 2018 (New)
Significant Accounting Policies [Line Items]
Interest rate on convertible notes	3.75%
Retained Earnings
Significant Accounting Policies [Line Items]
Cumulative-effect adjustment		$ 49,805		61,291
Retained Earnings | Accounting Standards Update 2016-09
Significant Accounting Policies [Line Items]
Cumulative-effect adjustment				$ 62,100