Debt Instrument, Interest Rate Floor

No definition available.

Name:	cien_DebtInstrumentInterestRateFloor
Namespace Prefix:	cien_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Debt Instrument, Periodic Payment, Principle, Percentage

+ References

No definition available.

+ Details

Name:	cien_DebtInstrumentPeriodicPaymentPrinciplePercentage
Namespace Prefix:	cien_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Debt Instrument, Prepayment Premium

+ References

No definition available.

+ Details

Name:	cien_DebtInstrumentPrepaymentPremium
Namespace Prefix:	cien_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of amortization expense attributable to debt issuance costs.

+ References

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-Publisher FASB
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+ Details

Name:	us-gaap_AmortizationOfFinancingCosts
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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+ Details

Name:	us-gaap_DebtInstrumentCarryingAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of the required periodic payments applied to principal.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

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+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

For a debtor, the aggregate gain (loss) recognized on the restructuring of payables arises from the difference between the book value of the debt before the restructuring and the fair value of the payments on the debt after restructuring is complete.

+ References

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-Name Accounting Standards Codification
-Topic 470
-SubTopic 60
-Section 50
-Paragraph 1
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+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

No definition available.

+ Details

Name:	us-gaap_LongTermDebtFairValue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Details

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_SecuredDebtMember
Namespace Prefix:
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Balance Type:
Period Type:

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=cien_NewTermLoan2025Member
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Period Type:

- Details

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Period Type:

- Details

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Short-Term and Long-Term Debt (Details) - Secured debt - USD ($) $ in Thousands		3 Months Ended
	Jan. 23, 2020	Jan. 31, 2020	Jan. 31, 2019	Oct. 31, 2019
Debt Instrument [Line Items]
Debt issuance costs, net		$ 3,400		$ 3,600
Amortization of debt issuance costs		200	$ 200
2025 Term Loan
Debt Instrument [Line Items]
Outstanding principal	$ 693,000	0
Debt issuance costs, net		0
New Term Loan 2025
Debt Instrument [Line Items]
Outstanding principal	693,000	693,000
Debt issuance costs for modification of debt	$ 100
Quarterly installments, percentage	0.25%
Quarterly installments	$ 1,730
Prepayment premium	1.00%
Debt issuance costs, net		$ 3,390
Fair value of debt	$ 694,700
LIBOR \| New Term Loan 2025
Debt Instrument [Line Items]
Applicable margin	1.75%
Interest rate floor	0.00%
Base Rate \| New Term Loan 2025
Debt Instrument [Line Items]
Applicable margin	0.75%
Interest rate floor	1.00%