Ciena Corporation and Significant Accounting Policies and Estimates (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended			12 Months Ended
	Oct. 31, 2011 months years	Oct. 31, 2011 4.0% Convertible Senior Notes due March 15, 2015 [Member]	Mar. 15, 2010 4.0% Convertible Senior Notes due March 15, 2015 [Member]	Oct. 31, 2010 Accounting Standards Update 2009-13 [Member]	Oct. 31, 2011 Equipment, Furniture and Fixtures [Member] years	Oct. 31, 2011 Software and Website Development [Member] years	Oct. 31, 2011 Maximum [Member]	Oct. 31, 2011 Minimum [Member]	Oct. 31, 2011 Privately Held Technology Company [Member]
Significant Accounting Policies [Line Items]
Fiscal year	52 or 53 week
Measurement period for cash and cash equivalents							3 months
Measurement period for marketable debt securities							1 year
Gain on sale of cost method investment									$ 7.2
Amount in escrow									1.0
Estimated useful lives capitalized and amortized straight-line, minimum (in years)					2	2
Estimated useful lives capitalized and amortized straight-line, maximum (in years)					5	5
Expected economic lives of finite-lived intangible assets, minimum (in months)	9
Expected economic lives of finite-lived intangible assets, maximum (in years)	7
Expected number of years Spares usage cost is expensed (in years)	4 years
Pro-forma revenue due to prospective adoption of new accounting pronouncement				$ 33.0
One-time employee termination benefits related to service period (in days)								60 days
Interest on convertible notes		4.00%	4.00%