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[Member] Deferred tax asset, net Deferred Income Tax Assets, Net Operating expenses: Operating Expenses [Abstract] Stock Appreciation Rights (SARs) Stock Appreciation Rights (SARs) [Member] Schedule of Ciena's Geographic Distribution of Revenue and Long-Lived Assets Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Geographical Area, Revenue and Long-Lived Asset [Table Text Block] Deferred compensation plan assets Deferred Compensation Plan Assets, Fair Value Disclosure Deferred Compensation Plan Assets, Fair Value Disclosure City Area Code City Area Code Accumulated Other Comprehensive Loss AOCI Attributable to Parent [Member] All Individuals All Individuals [Member] SUBSEQUENT EVENTS Subsequent Events [Text Block] Name Forgone Recovery, Individual Name Research and development expense: Research and Development [Abstract] Weighted-average period for recognition of share-based compensation (in years) Share-Based Payment Arrangement, Nonvested Award, 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Graff Arrangement, Restricted Stock [Member] Marc D. 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