CASH EQUIVALENT, SHORT-TERM AND LONG-TERM INVESTMENTS - Schedule of Legal Maturities of Debt Investments (Details) - USD ($) $ in Thousands	May 02, 2026	Nov. 01, 2025
Amortized Cost
Less than one year	$ 268,182
Due in 1-2 years	200,248
Amortized Cost	468,430	$ 342,258
Estimated Fair Value
Less than one year	268,271
Due in 1-2 years	200,106
Estimated Fair Value	$ 468,377	$ 342,828

Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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+ Details

- Definition

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

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+ Details

CIENA CORP 10-Q