DERIVATIVE INSTRUMENTS	9 Months Ended
DERIVATIVE INSTRUMENTS	Jul. 29, 2023
Derivative Instruments and Hedging Activities Disclosure [Abstract]
DERIVATIVE INSTRUMENTS	DERIVATIVE INSTRUMENTSForeign Currency Derivatives Ciena conducts business globally in numerous currencies, and thus is exposed to adverse foreign currency exchange rate changes. To limit this exposure, Ciena enters into foreign currency contracts. Ciena does not enter into such contracts for speculative purposes. As of July 29, 2023 and October 29, 2022, Ciena had forward contracts to hedge its foreign exchange exposure in order to reduce variability in certain currencies for expenses principally related to research and development activities. The notional amount of these contracts was approximately $291.4 million and $272.2 million as of July 29, 2023 and October 29, 2022, respectively. These foreign exchange contracts have maturities of 24 months or less and have been designated as cash flow hedges. In May 2023, Ciena entered into forward contracts designated as net investment hedges to minimize the effect of foreign exchange rate movements on its net investments in foreign operations. The notional amount of these contracts was approximately $48.6 million as of July 29, 2023. These foreign exchange contracts have maturities of 24 months or less and have been designated as net investment hedges. As of July 29, 2023 and October 29, 2022, Ciena had forward contracts to hedge its foreign exchange exposure in order to reduce the variability in various currencies of certain balance sheet items. The notional amount of these contracts was approximately $255.9 million and $108.0 million as of July 29, 2023 and October 29, 2022, respectively. These foreign exchange contracts have maturities of 12 months or less and have not been designated as hedges for accounting purposes. Interest Rate Derivatives Ciena is exposed to floating rates of interest on its term loan borrowings (see Note 16 below) and has hedged such risk by entering into floating-to-fixed interest rate swap arrangements. Prior to amending the 2025 Term Loan (as defined in Note 16 below) to replace LIBOR with the Secured Overnight Financing Rate (“SOFR”), Ciena was exposed to floating rates of LIBOR interest on its 2025 Term Loan borrowings. Ciena hedged this risk by entering into floating-to-fixed interest rate swap arrangements (“interest rate swaps”). The interest rate swaps fix the LIBOR rate for $350.0 million of the 2025 Term Loan at 2.957% through September 2023. In January 2023, Ciena entered into a LIBOR to SOFR basis swap (“basis swap”) to hedge its exposure to SOFR rate. The basis swap offsets the LIBOR exposure risk of the interest rate swaps and effectively fixes the SOFR rate for $350.0 million of the 2025 Term Loan at 2.883% through September 2023. The total notional amount of these swaps in effect was $350.0 million as of July 29, 2023 and October 29, 2022. In April 2022, Ciena entered into floating to fixed forward starting interest rate swap arrangements (“forward starting swaps”). The forward starting swaps fix the SOFR for $350.0 million of the 2025 Term Loan at 2.968% from September 2023 through the 2025 Term Loan maturity. The total notional amount of forward starting swaps effective September 2023 was $350.0 million as of July 29, 2023. In January 2023, Ciena entered into floating-to-fixed interest rate swap arrangements (“2028 interest rate swaps”). The 2028 interest rate swaps fix the SOFR rate of approximately $350.0 million of the principal amount of the 2030 Term Loan (as defined in Note 16 below) at 3.47% through January 2028. The total notional amount of these interest rate swaps in effect as of July 29, 2023 was $350.0 million. Ciena expects the variable rate payments to be received under the terms of the interest rate swaps, basis swap, forward starting swaps, and 2028 interest rate swaps to offset exactly the forecasted variable rate payments on the equivalent notional amounts of the 2025 Term Loan and 2030 Term Loan. These derivative contracts have been designated as cash flow hedges. Other information regarding Ciena’s derivatives is immaterial for separate financial statement presentation. See Note 6 and Note 9 above.