SHARE-BASED COMPENSATION EXPENSE - Assumptions for Awards Granted (Details) - Performance Based Awards	12 Months Ended
	Oct. 28, 2023	Oct. 29, 2022	Oct. 30, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected volatility of Ciena common stock, which is a weighted average of implied volatility and historical volatility	40.37%	38.27%	41.00%
Historical volatility of Ciena common stock	43.11%	42.17%	42.80%
Historical volatility of S&P Networking Index	30.93%	27.22%	27.30%
Correlation coefficient	0.7781	0.7049	0.6800
Expected life in years	2 years 10 months 20 days	2 years 10 months 20 days	2 years 10 months 13 days
Risk-free interest rate	3.95%	0.94%	0.17%
Expected dividend yield	0.00%	0.00%	0.00%