Interest And Other Income (Loss), Net (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Jan. 31, 2015	Jan. 31, 2014
Other Income and Expenses [Abstract]
Interest income	$ 218	$ 78
Change in fair value of embedded derivative	0us-gaap_UnrealizedGainLossOnDerivatives	(1,090)us-gaap_UnrealizedGainLossOnDerivatives
Gain (loss) on non-hedge designated foreign currency forward contracts	(4,350)	1,353
Foreign currency exchange losses	(3,652)	(5,915)
Other	(449)us-gaap_OtherNonoperatingIncome	(424)us-gaap_OtherNonoperatingIncome
Interest and other income (loss), net	$ (8,233)cien_InterestAndOtherIncomeNet	$ (5,998)cien_InterestAndOtherIncomeNet

Interest And Other Income Net.

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- Definition

Amount before tax of foreign currency transaction realized and unrealized gain (loss) recognized in the income statement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 830

-SubTopic 20

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6450189&loc=d3e30690-110894

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-Name Accounting Standards Codification

-Topic 830

-SubTopic 20

-Section 50

-Paragraph 1

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-Topic 830

-SubTopic 20

-Section 45

-Paragraph 2

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- Definition

Amount of gain (loss) recognized in earnings in the period from the increase (decrease) in fair value of foreign currency derivatives not designated as hedging instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4A

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=35706170&loc=SL5618551-113959

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-Name Accounting Standards Codification

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-Section 50

-Paragraph 4C

-Subparagraph (e)

-URI http://asc.fasb.org/extlink&oid=35706170&loc=SL5624171-113959

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- Definition

The net amount of nonoperating interest income (expense).

+ References

No definition available.

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- Definition

The aggregate amount of other income amounts, the components of which are not separately disclosed on the income statement, resulting from ancillary business-related activities (that is, excluding major activities considered part of the normal operations of the business) also known as other nonoperating income recognized for the period. Such amounts may include: (a) dividends, (b) interest on securities, (c) profits on securities (net of losses), and (d) miscellaneous other income items.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.7)

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 7

-Article 5

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- Definition

The net change in the difference between the fair value and the carrying value, or in the comparative fair values, of derivative instruments, including options, swaps, futures, and forward contracts, held at each balance sheet date, that was included in earnings for the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

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