Business Combination, Contingent Consideration Arrangements, Basis for Amount, Term

No definition available.

Name:	cien_BusinessCombinationContingentConsiderationArrangementsBasisforAmountTerm
Namespace Prefix:	cien_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Business Combination, Contingent Consideration Arrangements, Term

+ References

No definition available.

+ Details

Name:	cien_BusinessCombinationContingentConsiderationArrangementsTerm
Namespace Prefix:	cien_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16265-109275

+ Details

Name:	us-gaap_AcquiredFiniteLivedIntangibleAssetsWeightedAverageUsefulLife
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

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

- Definition

This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 25
-Paragraph 23
-URI http://asc.fasb.org/extlink&oid=116868678&loc=d3e1043-128460

+ Details

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

- Definition

Amount of increase (decrease) in the value of a contingent consideration liability, including, but not limited to, differences arising upon settlement.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3602-108585

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 4
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=120321790&loc=d3e7008-128479

+ Details

Name:	us-gaap_BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiability1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

For contingent consideration arrangements recognized in connection with a business combination, this element represents an estimate of the high-end of the potential range (undiscounted) of the consideration which may be paid.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (c)(3)
-URI http://asc.fasb.org/extlink&oid=120321790&loc=d3e6927-128479

+ Details

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

- Definition

For contingent consideration arrangements and indemnification assets recognized in connection with a business combination, this element represents an estimate of the low-end of the potential range (undiscounted) of the consideration which may be paid.

+ References

+ Details

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

- Definition

Amount of liability recognized arising from contingent consideration in a business combination.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=120321790&loc=d3e6927-128479

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 35
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=116859824&loc=d3e6819-128478

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 25
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=6911189&loc=d3e6408-128476

+ Details

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

- Definition

Amount of cash outflow, not made soon after acquisition date of business combination, to settle contingent consideration liability exceeding amount recognized at acquisition date. Includes, but is not limited to, measurement period adjustment and less amount paid soon after acquisition date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 17
-Subparagraph (ee)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3367-108585

+ Details

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

- Definition

The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

+ References

+ Details

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

- Details

Name:	us-gaap_BusinessAcquisitionAxis=cien_CentinaSystemsInc.Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis=cien_CustomerRelationshipsAndContractsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis=us-gaap_DevelopedTechnologyRightsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_BusinessAcquisitionAxis=cien_DonRiverHoldingsLLCMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_BusinessAcquisitionAxis=cien_PacketDesignLLCMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ContingentConsiderationByTypeAxis=cien_ContingentConsiderationMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ContingentConsiderationByTypeAxis=cien_ContingentCompensationMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Business Combinations (Details) - USD ($)				12 Months Ended			13 Months Ended
Business Combinations (Details) - USD ($)	Nov. 02, 2019	Oct. 01, 2018	Jul. 02, 2018	Oct. 31, 2020	Nov. 02, 2019	Nov. 03, 2018	Oct. 31, 2019
Business Acquisition [Line Items]
Acquisition-related costs				$ 4,031,000	$ 3,370,000	$ 5,111,000
Contingent consideration agreement term					3 years
Contingent consideration	$ 4,372,000			0	$ 4,372,000
Centina Systems, Inc.
Business Acquisition [Line Items]
Payment to acquire business	$ 34,000,000.0
Acquisition-related costs				800,000
Centina Systems, Inc. \| Customer relationships and contracts
Business Acquisition [Line Items]
Intangible assets, useful life	2 years
Centina Systems, Inc. \| Developed technology
Business Acquisition [Line Items]
Intangible assets, useful life	5 years
DonRiver
Business Acquisition [Line Items]
Payment to acquire business		$ 43,283,000
Acquisition-related costs				6,900,000	7,500,000	3,500,000
Undiscounted contingent consideration, maximum		$ 28,500,000
Contingent consideration agreement term		3 years
Contingent consideration revenue measurement term		25 months
Change in contingent consideration				(3,700,000)			$ (2,800,000)
Contingent consideration	$ 8,100,000	$ 10,900,000		0	8,100,000
Contingent consideration paid				4,400,000
DonRiver \| Customer relationships and contracts
Business Acquisition [Line Items]
Intangible assets, useful life		7 years
DonRiver \| Developed technology
Business Acquisition [Line Items]
Intangible assets, useful life		7 years
Packet Design
Business Acquisition [Line Items]
Payment to acquire business			$ 41,100,000
Acquisition-related costs						1,600,000
Packet Design \| Customer relationships and contracts
Business Acquisition [Line Items]
Intangible assets, useful life			3 years
Packet Design \| Developed technology
Business Acquisition [Line Items]
Intangible assets, useful life			5 years
Contingent Consideration \| DonRiver
Business Acquisition [Line Items]
Undiscounted contingent consideration, maximum		$ 15,000,000.0
Undiscounted contingent consideration, minimum		0.0
Contingent Compensation \| DonRiver
Business Acquisition [Line Items]
Undiscounted contingent consideration, maximum		13,500,000
Undiscounted contingent consideration, minimum		$ 0.0
Change in contingent consideration				$ 6,900,000	$ 5,100,000	$ 400,000