$CIEN
CIENA CORP Stock $cien

$cien Overview Financials Valuation SEC Filings Company Website

2020 Q4 Form 10-K Financial Statement

#000093639520000042 Filed on December 18, 2020

Income Statement

Concept	2020 Q4	2019 Q4	2018
Revenue	$828.5M	$968.0M	$3.094B
YoY Change	-14.41%	7.63%	10.44%
Cost Of Revenue	$424.1M	$548.3M	$1.780B
YoY Change	-22.65%	9.38%	14.38%
Gross Profit	$404.3M	$419.7M	$1.315B
YoY Change	-3.67%	5.43%	5.53%
Gross Profit Margin	48.8%	43.36%	42.49%
Selling, General & Admin	$156.8M	$167.5M	$554.2M
YoY Change	-6.39%	6.48%	11.11%
% of Gross Profit	38.78%	39.91%	42.15%
Research & Development	$137.2M	$141.7M	$491.6M
YoY Change	-3.18%	4.96%	3.42%
% of Gross Profit	33.94%	33.76%	37.39%
Depreciation & Amortization	$33.10M	$31.00M	$84.21M
YoY Change	6.77%	8.01%	9.1%
% of Gross Profit	8.19%	7.39%	6.41%
Operating Expenses	$299.9M	$314.4M	$1.085B
YoY Change	-4.61%	5.89%	5.21%
Operating Profit	$104.4M	$105.3M	$229.9M
YoY Change	-0.85%	4.05%	7.09%
Interest Expense	-$9.900M	-$10.00M	$55.25M
YoY Change	-1.0%	-36.71%	-1.08%
% of Operating Profit	-9.48%	-9.5%	24.03%
Other Income/Expense, Net	$2.300M	-$300.0K	-$1.019M
YoY Change	-866.67%	-25.0%	1007.61%
Pretax Income	$85.80M	$82.90M	$107.0M
YoY Change	3.5%	54.09%	-6.36%
Income Tax	$20.80M	$2.600M	$493.5M
% Of Pretax Income	24.24%	3.14%	461.31%
Net Earnings	$65.00M	$80.30M	-$344.7M
YoY Change	-19.05%	25.47%	-127.31%
Net Earnings / Revenue	7.85%	8.3%	-11.14%
Basic Earnings Per Share			-$2.40
Diluted Earnings Per Share	$415.1K	$512.8K	-$2.49
COMMON SHARES
Basic Shares Outstanding	154.6M shares	154.1M shares	143.7M shares
Diluted Shares Outstanding			143.7M shares

Balance Sheet

Concept	2020 Q4	2019 Q4	2018
SHORT-TERM ASSETS
Cash & Short-Term Investments	$1.239B	$1.014B	$894.4M
YoY Change	22.22%	13.37%	-2.74%
Cash & Equivalents	$1.089B	$904.0M	$745.4M
Short-Term Investments	$150.7M	$109.9M	$149.0M
Other Short-Term Assets	$286.1M	$269.8M	$172.6M
YoY Change	6.04%	56.32%	-7.05%
Inventory	$344.4M	$345.0M	$262.8M
Prepaid Expenses
Receivables	$719.4M	$724.9M	$786.5M
Other Receivables	$22.00M	$28.10M	$26.30M
Total Short-Term Assets	$2.611B	$2.382B	$2.143B
YoY Change	9.63%	11.16%	6.79%
LONG-TERM ASSETS
Property, Plant & Equipment	$329.4M	$286.9M	$292.1M
YoY Change	14.82%	-1.77%	-5.32%
Goodwill	$310.8M	$297.9M
YoY Change	4.33%	-0.01%
Intangibles	$96.65M	$112.8M
YoY Change	-14.31%	-23.91%
Long-Term Investments	$82.20M	$20.70M	$67.00M
YoY Change	297.1%	-69.1%	20.07%
Other Assets	$102.8M	$88.99M	$808.6M
YoY Change	15.56%	24.19%	-33.26%
Total Long-Term Assets	$1.570B	$1.565B	$1.614B
YoY Change	0.31%	-4.29%	-17.04%
TOTAL ASSETS
Total Short-Term Assets	$2.611B	$2.382B	$2.143B
Total Long-Term Assets	$1.570B	$1.565B	$1.614B
Total Assets	$4.181B	$3.947B	$3.757B
YoY Change	5.94%	4.48%	-4.94%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$291.9M	$344.8M	$340.6M
YoY Change	-15.35%	1.24%	30.95%
Accrued Expenses	$334.1M	$382.7M	$336.5M
YoY Change	-12.7%	12.55%	5.42%
Deferred Revenue	$108.7M	$111.4M
YoY Change	-2.41%	0.22%
Short-Term Debt	$0.00	$0.00	$0.00
YoY Change
Long-Term Debt Due	$6.930M	$7.000M	$10.50M
YoY Change	-1.0%	-33.33%	-97.05%
Total Short-Term Liabilities	$760.7M	$845.9M	$963.0M
YoY Change	-10.08%	-12.16%	-7.2%
LONG-TERM LIABILITIES
Long-Term Debt	$676.4M	$680.4M	$754.7M
YoY Change	-0.6%	-0.88%	14.85%
Other Long-Term Liabilities	$123.2M	$148.7M	$109.5M
YoY Change	-17.18%	24.57%	-9.13%
Total Long-Term Liabilities	$799.5M	$829.2M	$864.2M
YoY Change	-3.57%	2.89%	11.14%
TOTAL LIABILITIES
Total Short-Term Liabilities	$760.7M	$845.9M	$963.0M
Total Long-Term Liabilities	$799.5M	$829.2M	$864.2M
Total Liabilities	$1.671B	$1.721B	$1.827B
YoY Change	-2.86%	-5.83%	0.65%
SHAREHOLDERS EQUITY
Retained Earnings	-$4.283B	-$4.644B
YoY Change	-7.78%	-5.17%
Common Stock	$6.828B	$6.839B
YoY Change	-0.16%	-0.63%
Preferred Stock
YoY Change
Treasury Stock (at cost)
YoY Change
Treasury Stock Shares
Shareholders Equity	$2.510B	$2.173B	$1.929B
YoY Change
Total Liabilities & Shareholders Equity	$4.181B	$3.947B	$3.757B
YoY Change	5.94%	4.48%	-4.94%

Cashflow Statement

Concept	2020 Q4	2019 Q4	2018
OPERATING ACTIVITIES
Net Income	$65.00M	$80.30M	-$344.7M
YoY Change	-19.05%	25.47%	-127.31%
Depreciation, Depletion And Amortization	$33.10M	$31.00M	$84.21M
YoY Change	6.77%	8.01%	9.1%
Cash From Operating Activities	$187.3M	$240.0M	$229.3M
YoY Change	-21.96%	252.42%	-2.39%
INVESTING ACTIVITIES
Capital Expenditures	-$21.40M	-$13.50M	$67.62M
YoY Change	58.52%	-21.51%	-28.52%
Acquisitions			$82.67M
YoY Change
Other Investing Activities	-$162.5M	$1.900M	$48.20M
YoY Change	-8652.63%	-85.38%	45.18%
Cash From Investing Activities	-$183.8M	-$11.70M	-$19.38M
YoY Change	1470.94%	178.57%	-68.42%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net			$87.85M
YoY Change			-530.4%
Debt Paid & Issued, Net			$292.7M
YoY Change			25.34%
Cash From Financing Activities	-8.400M	-49.10M	-$99.23M
YoY Change	-82.89%	15.26%	-68.1%
NET CHANGE
Cash From Operating Activities	187.3M	240.0M	$229.3M
Cash From Investing Activities	-183.8M	-11.70M	-$19.38M
Cash From Financing Activities	-8.400M	-49.10M	-$99.23M
Net Change In Cash	-4.900M	179.2M	$104.8M
YoY Change	-102.73%	741.31%	-176.46%
FREE CASH FLOW
Cash From Operating Activities	$187.3M	$240.0M	$229.3M
Capital Expenditures	-$21.40M	-$13.50M	$67.62M
Free Cash Flow	$208.7M	$253.5M	$161.6M
YoY Change	-17.67%	197.19%	15.23%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
CY2020	dei	Entity Central Index Key EntityCentralIndexKey	0000936395
CY2020	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2020
CY2020	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	FY
CY2020	dei	Amendment Flag AmendmentFlag	false
CY2020Q4	us-gaap	Finance Lease Right Of Use Asset Statement Of Financial Position Extensible List FinanceLeaseRightOfUseAssetStatementOfFinancialPositionExtensibleList	us-gaap:PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAfterAccumulatedDepreciationAndAmortization
CY2020	dei	Document Type DocumentType	10-K
CY2020	dei	Document Annual Report DocumentAnnualReport	true
CY2020	dei	Document Period End Date DocumentPeriodEndDate	2020-10-31
CY2020	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--10-31
CY2020	dei	Document Transition Report DocumentTransitionReport	false
CY2020	dei	Entity File Number EntityFileNumber	001-36250
CY2020	dei	Entity Registrant Name EntityRegistrantName	Ciena Corp
CY2020	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	DE
CY2020	dei	Entity Address Address Line1 EntityAddressAddressLine1	7035 Ridge Road
CY2020	dei	Entity Address State Or Province EntityAddressStateOrProvince	MD
CY2020	dei	Entity Address City Or Town EntityAddressCityOrTown	Hanover
CY2020	dei	Entity Tax Identification Number EntityTaxIdentificationNumber	23-2725311
CY2020	dei	Entity Address Postal Zip Code EntityAddressPostalZipCode	21076
CY2020	dei	City Area Code CityAreaCode	410
CY2020	dei	Local Phone Number LocalPhoneNumber	694-5700
CY2020	dei	Security12b Title Security12bTitle	Common Stock, $0.01 par value
CY2020	dei	Trading Symbol TradingSymbol	CIEN
CY2020	dei	Security Exchange Name SecurityExchangeName	NYSE
CY2020	dei	Entity Well Known Seasoned Issuer EntityWellKnownSeasonedIssuer	Yes
CY2020	dei	Entity Voluntary Filers EntityVoluntaryFilers	No
CY2020	dei	Entity Current Reporting Status EntityCurrentReportingStatus	Yes
CY2020	dei	Entity Interactive Data Current EntityInteractiveDataCurrent	Yes
CY2020	dei	Entity Filer Category EntityFilerCategory	Large Accelerated Filer
CY2020	dei	Entity Small Business EntitySmallBusiness	false
CY2020	dei	Entity Emerging Growth Company EntityEmergingGrowthCompany	false
CY2020	dei	Icfr Auditor Attestation Flag IcfrAuditorAttestationFlag	true
CY2020	dei	Entity Shell Company EntityShellCompany	false
CY2020Q2	dei	Entity Public Float EntityPublicFloat	7100000000	USD
CY2020Q4	dei	Entity Common Stock Shares Outstanding EntityCommonStockSharesOutstanding	154564349	shares
CY2020Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	1088624000	USD
CY2019Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	904045000	USD
CY2020Q4	us-gaap	Short Term Investments ShortTermInvestments	150667000	USD
CY2019Q4	us-gaap	Short Term Investments ShortTermInvestments	109940000	USD
CY2020Q4	us-gaap	Accounts Receivable Net Current AccountsReceivableNetCurrent	719405000	USD
CY2019Q4	us-gaap	Accounts Receivable Net Current AccountsReceivableNetCurrent	724854000	USD
CY2020Q4	us-gaap	Inventory Net InventoryNet	344379000	USD
CY2019Q4	us-gaap	Inventory Net InventoryNet	345049000	USD
CY2020Q4	us-gaap	Prepaid Expense And Other Assets Current PrepaidExpenseAndOtherAssetsCurrent	308084000	USD
CY2019Q4	us-gaap	Prepaid Expense And Other Assets Current PrepaidExpenseAndOtherAssetsCurrent	297914000	USD
CY2020Q4	us-gaap	Assets Current AssetsCurrent	2611159000	USD
CY2019Q4	us-gaap	Assets Current AssetsCurrent	2381802000	USD
CY2020Q4	us-gaap	Marketable Securities Noncurrent MarketableSecuritiesNoncurrent	82226000	USD
CY2019Q4	us-gaap	Marketable Securities Noncurrent MarketableSecuritiesNoncurrent	10014000	USD
CY2020Q4	us-gaap	Property Plant And Equipment And Finance Lease Right Of Use Asset After Accumulated Depreciation And Amortization PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAfterAccumulatedDepreciationAndAmortization	272377000	USD
CY2019Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	286884000	USD
CY2020Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	57026000	USD
CY2020Q4	us-gaap	Goodwill Goodwill	310847000	USD
CY2019Q4	us-gaap	Goodwill Goodwill	297937000	USD
CY2020Q4	us-gaap	Intangible Assets Net Excluding Goodwill IntangibleAssetsNetExcludingGoodwill	96647000	USD
CY2019Q4	us-gaap	Intangible Assets Net Excluding Goodwill IntangibleAssetsNetExcludingGoodwill	112781000	USD
CY2020Q4	us-gaap	Deferred Income Tax Assets Net DeferredIncomeTaxAssetsNet	647805000	USD
CY2019Q4	us-gaap	Deferred Income Tax Assets Net DeferredIncomeTaxAssetsNet	714942000	USD
CY2020Q4	us-gaap	Other Assets Noncurrent OtherAssetsNoncurrent	102830000	USD
CY2019Q4	us-gaap	Other Assets Noncurrent OtherAssetsNoncurrent	88986000	USD
CY2020Q4	us-gaap	Assets Assets	4180917000	USD
CY2019Q4	us-gaap	Assets Assets	3893346000	USD
CY2020Q4	us-gaap	Accounts Payable Current AccountsPayableCurrent	291904000	USD
CY2019Q4	us-gaap	Accounts Payable Current AccountsPayableCurrent	344819000	USD
CY2020Q4	us-gaap	Accrued Liabilities Current AccruedLiabilitiesCurrent	334132000	USD
CY2019Q4	us-gaap	Accrued Liabilities Current AccruedLiabilitiesCurrent	382740000	USD
CY2020Q4	us-gaap	Contract With Customer Liability Current ContractWithCustomerLiabilityCurrent	108700000	USD
CY2019Q4	us-gaap	Contract With Customer Liability Current ContractWithCustomerLiabilityCurrent	111381000	USD
CY2020Q4	us-gaap	Operating Lease Liability Current OperatingLeaseLiabilityCurrent	19035000	USD
CY2020Q4	us-gaap	Long Term Debt Current LongTermDebtCurrent	6930000	USD
CY2019Q4	us-gaap	Long Term Debt Current LongTermDebtCurrent	7000000	USD
CY2020Q4	us-gaap	Liabilities Current LiabilitiesCurrent	760701000	USD
CY2019Q4	us-gaap	Liabilities Current LiabilitiesCurrent	845940000	USD
CY2020Q4	us-gaap	Contract With Customer Liability Noncurrent ContractWithCustomerLiabilityNoncurrent	49663000	USD
CY2019Q4	us-gaap	Contract With Customer Liability Noncurrent ContractWithCustomerLiabilityNoncurrent	45492000	USD
CY2020Q4	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	123185000	USD
CY2019Q4	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	148747000	USD
CY2020Q4	us-gaap	Operating Lease Liability Noncurrent OperatingLeaseLiabilityNoncurrent	61415000	USD
CY2020Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	676356000	USD
CY2019Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	680406000	USD
CY2020Q4	us-gaap	Liabilities Liabilities	1671320000	USD
CY2019Q4	us-gaap	Liabilities Liabilities	1720585000	USD
CY2020Q4	us-gaap	Commitments And Contingencies CommitmentsAndContingencies		USD
CY2019Q4	us-gaap	Commitments And Contingencies CommitmentsAndContingencies		USD
CY2019Q4	us-gaap	Preferred Stock Par Or Stated Value Per Share PreferredStockParOrStatedValuePerShare	0.01
CY2020Q4	us-gaap	Preferred Stock Par Or Stated Value Per Share PreferredStockParOrStatedValuePerShare	0.01
CY2020Q4	us-gaap	Preferred Stock Shares Authorized PreferredStockSharesAuthorized	20000000	shares
CY2019Q4	us-gaap	Preferred Stock Shares Authorized PreferredStockSharesAuthorized	20000000	shares
CY2020Q4	us-gaap	Preferred Stock Shares Outstanding PreferredStockSharesOutstanding	0	shares
CY2019Q4	us-gaap	Preferred Stock Shares Issued PreferredStockSharesIssued	0	shares
CY2019Q4	us-gaap	Preferred Stock Shares Outstanding PreferredStockSharesOutstanding	0	shares
CY2020Q4	us-gaap	Preferred Stock Shares Issued PreferredStockSharesIssued	0	shares
CY2020Q4	us-gaap	Preferred Stock Value PreferredStockValue	0	USD
CY2019Q4	us-gaap	Preferred Stock Value PreferredStockValue	0	USD
CY2019Q4	us-gaap	Common Stock Par Or Stated Value Per Share CommonStockParOrStatedValuePerShare	0.01
CY2020Q4	us-gaap	Common Stock Par Or Stated Value Per Share CommonStockParOrStatedValuePerShare	0.01
CY2020Q4	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	290000000	shares
CY2019Q4	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	290000000	shares
CY2020Q4	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	154563005	shares
CY2020Q4	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	154563005	shares
CY2019Q4	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	154403850	shares
CY2019Q4	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	154403850	shares
CY2020Q4	us-gaap	Common Stock Value CommonStockValue	1546000	USD
CY2019Q4	us-gaap	Common Stock Value CommonStockValue	1544000	USD
CY2020Q4	us-gaap	Additional Paid In Capital Common Stock AdditionalPaidInCapitalCommonStock	6826531000	USD
CY2019Q4	us-gaap	Additional Paid In Capital Common Stock AdditionalPaidInCapitalCommonStock	6837714000	USD
CY2020Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-35358000	USD
CY2019Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-22084000	USD
CY2020Q4	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	-4283122000	USD
CY2019Q4	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	-4644413000	USD
CY2020Q4	us-gaap	Stockholders Equity StockholdersEquity	2509597000	USD
CY2019Q4	us-gaap	Stockholders Equity StockholdersEquity	2172761000	USD
CY2020Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	4180917000	USD
CY2019Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	3893346000	USD
CY2020	us-gaap	Revenues Revenues	3532157000	USD
CY2019	us-gaap	Revenues Revenues	3572131000	USD
CY2018	us-gaap	Revenues Revenues	3094286000	USD
CY2020	us-gaap	Cost Of Goods And Services Sold CostOfGoodsAndServicesSold	1879266000	USD
CY2019	us-gaap	Cost Of Goods And Services Sold CostOfGoodsAndServicesSold	2030065000	USD
CY2018	us-gaap	Cost Of Goods And Services Sold CostOfGoodsAndServicesSold	1779596000	USD
CY2020	us-gaap	Gross Profit GrossProfit	1652891000	USD
CY2019	us-gaap	Gross Profit GrossProfit	1542066000	USD
CY2018	us-gaap	Gross Profit GrossProfit	1314690000	USD
CY2020	us-gaap	Research And Development Expense ResearchAndDevelopmentExpense	529888000	USD
CY2019	us-gaap	Research And Development Expense ResearchAndDevelopmentExpense	548139000	USD
CY2018	us-gaap	Research And Development Expense ResearchAndDevelopmentExpense	491564000	USD
CY2020	us-gaap	Selling And Marketing Expense SellingAndMarketingExpense	416425000	USD
CY2019	us-gaap	Selling And Marketing Expense SellingAndMarketingExpense	423046000	USD
CY2018	us-gaap	Selling And Marketing Expense SellingAndMarketingExpense	394060000	USD
CY2020	us-gaap	General And Administrative Expense GeneralAndAdministrativeExpense	169548000	USD
CY2019	us-gaap	General And Administrative Expense GeneralAndAdministrativeExpense	174399000	USD
CY2018	us-gaap	General And Administrative Expense GeneralAndAdministrativeExpense	160133000	USD
CY2020	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	23383000	USD
CY2019	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	21808000	USD
CY2018	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	15737000	USD
CY2020	us-gaap	Business Combination Acquisition Related Costs BusinessCombinationAcquisitionRelatedCosts	4031000	USD
CY2019	us-gaap	Business Combination Acquisition Related Costs BusinessCombinationAcquisitionRelatedCosts	3370000	USD
CY2018	us-gaap	Business Combination Acquisition Related Costs BusinessCombinationAcquisitionRelatedCosts	5111000	USD
CY2020	us-gaap	Restructuring Costs And Asset Impairment Charges RestructuringCostsAndAssetImpairmentCharges	22652000	USD
CY2019	us-gaap	Restructuring Costs And Asset Impairment Charges RestructuringCostsAndAssetImpairmentCharges	24538000	USD
CY2018	us-gaap	Restructuring Costs And Asset Impairment Charges RestructuringCostsAndAssetImpairmentCharges	18139000	USD
CY2020	us-gaap	Operating Expenses OperatingExpenses	1165927000	USD
CY2019	us-gaap	Operating Expenses OperatingExpenses	1195300000	USD
CY2018	us-gaap	Operating Expenses OperatingExpenses	1084744000	USD
CY2020	us-gaap	Operating Income Loss OperatingIncomeLoss	486964000	USD
CY2019	us-gaap	Operating Income Loss OperatingIncomeLoss	346766000	USD
CY2018	us-gaap	Operating Income Loss OperatingIncomeLoss	229946000	USD
CY2020	cien	Interest And Other Income Loss Net InterestAndOtherIncomeLossNet	964000	USD
CY2019	cien	Interest And Other Income Loss Net InterestAndOtherIncomeLossNet	3876000	USD
CY2018	cien	Interest And Other Income Loss Net InterestAndOtherIncomeLossNet	-12029000	USD
CY2020	us-gaap	Interest Expense InterestExpense	31321000	USD
CY2019	us-gaap	Interest Expense InterestExpense	37452000	USD
CY2018	us-gaap	Interest Expense InterestExpense	55249000	USD
CY2020	cien	Gain Losson Extinguishmentand Restructuringof Debt GainLossonExtinguishmentandRestructuringofDebt	-646000	USD
CY2019	cien	Gain Losson Extinguishmentand Restructuringof Debt GainLossonExtinguishmentandRestructuringofDebt	0	USD
CY2018	cien	Gain Losson Extinguishmentand Restructuringof Debt GainLossonExtinguishmentandRestructuringofDebt	-13887000	USD
CY2020	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	455961000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	313190000	USD
CY2018	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	148781000	USD
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	94670000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	59756000	USD
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	493471000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	361291000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	253434000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	-344690000	USD
CY2020	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.34
CY2019	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.63
CY2018	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	-2.40
CY2020	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.32
CY2019	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.61
CY2018	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	-2.49
CY2020	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	154287000	shares
CY2019	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	155720000	shares
CY2018	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	143738000	shares
CY2020	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	155955000	shares
CY2019	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	157612000	shares
CY2018	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	143738000	shares
CY2020	us-gaap	Net Income Loss NetIncomeLoss	361291000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	253434000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	-344690000	USD
CY2020	us-gaap	Other Comprehensive Income Availableforsale Securities Adjustment Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeAvailableforsaleSecuritiesAdjustmentNetOfTaxPortionAttributableToParent	-107000	USD
CY2019	us-gaap	Other Comprehensive Income Availableforsale Securities Adjustment Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeAvailableforsaleSecuritiesAdjustmentNetOfTaxPortionAttributableToParent	577000	USD
CY2018	us-gaap	Other Comprehensive Income Availableforsale Securities Adjustment Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeAvailableforsaleSecuritiesAdjustmentNetOfTaxPortionAttributableToParent	26000	USD
CY2020	us-gaap	Other Comprehensive Income Foreign Currency Transaction And Translation Adjustment Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationAdjustmentNetOfTaxPortionAttributableToParent	-4174000	USD
CY2019	us-gaap	Other Comprehensive Income Foreign Currency Transaction And Translation Adjustment Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationAdjustmentNetOfTaxPortionAttributableToParent	-763000	USD
CY2018	us-gaap	Other Comprehensive Income Foreign Currency Transaction And Translation Adjustment Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationAdjustmentNetOfTaxPortionAttributableToParent	686000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-13274000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-16304000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	5237000	USD
CY2020	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	348017000	USD
CY2019	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	237130000	USD
CY2018	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	-339453000	USD
CY2017Q4	us-gaap	Stockholders Equity StockholdersEquity	2136342000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	-344690000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	5237000	USD
CY2018	cien	Adjustmentsto Additional Paidin Capital Embedded Derivative Liability AdjustmentstoAdditionalPaidinCapitalEmbeddedDerivativeLiability	-152142000	USD
CY2018	us-gaap	Stock Issued During Period Value Conversion Of Convertible Securities Net Of Adjustments StockIssuedDuringPeriodValueConversionOfConvertibleSecuritiesNetOfAdjustments	262103000	USD
CY2018	cien	Stock Repurchased During Period Excluding Shares Purchasedfor Tax Withholdingsfor Sharebased Compensation Value StockRepurchasedDuringPeriodExcludingSharesPurchasedforTaxWithholdingsforSharebasedCompensationValue	110981000	USD
CY2018	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	23127000	USD
CY2018	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	52972000	USD
CY2018	cien	Stock Repurchased During Period Shares Purchasedfor Tax Withholdingsfor Sharebased Compensation Value StockRepurchasedDuringPeriodSharesPurchasedforTaxWithholdingsforSharebasedCompensationValue	4757000	USD
CY2018Q4	us-gaap	Stockholders Equity StockholdersEquity	1929334000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	253434000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-16304000	USD
CY2019	cien	Stock Repurchased During Period Excluding Shares Purchasedfor Tax Withholdingsfor Sharebased Compensation Value StockRepurchasedDuringPeriodExcludingSharesPurchasedforTaxWithholdingsforSharebasedCompensationValue	150076000	USD
CY2019	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	22947000	USD
CY2019	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	59736000	USD
CY2019	us-gaap	Stock Issued During Period Value Conversion Of Convertible Securities Net Of Adjustments StockIssuedDuringPeriodValueConversionOfConvertibleSecuritiesNetOfAdjustments	52944000	USD
CY2019	cien	Stock Repurchased During Period Shares Purchasedfor Tax Withholdingsfor Sharebased Compensation Value StockRepurchasedDuringPeriodSharesPurchasedforTaxWithholdingsforSharebasedCompensationValue	29059000	USD
CY2019Q4	us-gaap	Stockholders Equity StockholdersEquity	2172761000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	361291000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-13274000	USD
CY2020	cien	Stock Repurchased During Period Excluding Shares Purchasedfor Tax Withholdingsfor Sharebased Compensation Value StockRepurchasedDuringPeriodExcludingSharesPurchasedforTaxWithholdingsforSharebasedCompensationValue	74535000	USD
CY2020	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	28068000	USD
CY2020	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	67758000	USD
CY2020	cien	Stock Repurchased During Period Shares Purchasedfor Tax Withholdingsfor Sharebased Compensation Value StockRepurchasedDuringPeriodSharesPurchasedforTaxWithholdingsforSharebasedCompensationValue	32472000	USD
CY2020Q4	us-gaap	Stockholders Equity StockholdersEquity	2509597000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	361291000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	253434000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	-344690000	USD
CY2020	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	0	USD
CY2019	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	0	USD
CY2018	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	-10039000	USD
CY2020	us-gaap	Embedded Derivative Gain Loss On Embedded Derivative Net EmbeddedDerivativeGainLossOnEmbeddedDerivativeNet	0	USD
CY2019	us-gaap	Embedded Derivative Gain Loss On Embedded Derivative Net EmbeddedDerivativeGainLossOnEmbeddedDerivativeNet	0	USD
CY2018	us-gaap	Embedded Derivative Gain Loss On Embedded Derivative Net EmbeddedDerivativeGainLossOnEmbeddedDerivativeNet	-12070000	USD
CY2020	us-gaap	Depreciation Depreciation	93908000	USD
CY2019	us-gaap	Depreciation Depreciation	87576000	USD
CY2018	us-gaap	Depreciation Depreciation	84214000	USD
CY2020	us-gaap	Share Based Compensation ShareBasedCompensation	67758000	USD
CY2019	us-gaap	Share Based Compensation ShareBasedCompensation	59736000	USD
CY2018	us-gaap	Share Based Compensation ShareBasedCompensation	52972000	USD
CY2020	cien	Amortization Of Intangible Assets Excluding Amortization Included In Property Plant And Equipment AmortizationOfIntangibleAssetsExcludingAmortizationIncludedInPropertyPlantAndEquipment	38619000	USD
CY2019	cien	Amortization Of Intangible Assets Excluding Amortization Included In Property Plant And Equipment AmortizationOfIntangibleAssetsExcludingAmortizationIncludedInPropertyPlantAndEquipment	35136000	USD
CY2018	cien	Amortization Of Intangible Assets Excluding Amortization Included In Property Plant And Equipment AmortizationOfIntangibleAssetsExcludingAmortizationIncludedInPropertyPlantAndEquipment	25806000	USD
CY2020	us-gaap	Deferred Income Taxes And Tax Credits DeferredIncomeTaxesAndTaxCredits	64339000	USD
CY2019	us-gaap	Deferred Income Taxes And Tax Credits DeferredIncomeTaxesAndTaxCredits	19865000	USD
CY2018	us-gaap	Deferred Income Taxes And Tax Credits DeferredIncomeTaxesAndTaxCredits	463631000	USD
CY2020	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	8855000	USD
CY2019	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	6740000	USD
CY2020	us-gaap	Increase Decrease In Prepaid Deferred Expense And Other Assets IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets	38998000	USD
CY2019	us-gaap	Increase Decrease In Prepaid Deferred Expense And Other Assets IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets	96618000	USD
CY2018	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	2700000	USD
CY2020	us-gaap	Inventory Write Down InventoryWriteDown	24701000	USD
CY2019	us-gaap	Inventory Write Down InventoryWriteDown	28085000	USD
CY2018	us-gaap	Inventory Write Down InventoryWriteDown	30615000	USD
CY2020	us-gaap	Product Warranty Expense ProductWarrantyExpense	22417000	USD
CY2019	us-gaap	Product Warranty Expense ProductWarrantyExpense	23105000	USD
CY2018	us-gaap	Product Warranty Expense ProductWarrantyExpense	20992000	USD
CY2020	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	-11628000	USD
CY2019	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	910000	USD
CY2018	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	-21685000	USD
CY2020	us-gaap	Increase Decrease In Accounts Receivable IncreaseDecreaseInAccountsReceivable	17299000	USD
CY2019	us-gaap	Increase Decrease In Accounts Receivable IncreaseDecreaseInAccountsReceivable	-65712000	USD
CY2018	us-gaap	Increase Decrease In Accounts Receivable IncreaseDecreaseInAccountsReceivable	168357000	USD
CY2020	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	25044000	USD
CY2019	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	112941000	USD
CY2018	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	27445000	USD
CY2018	us-gaap	Increase Decrease In Prepaid Deferred Expense And Other Assets IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets	21425000	USD
CY2020	cien	Increase Decrease In Operating Lease Right Of Use Assets IncreaseDecreaseInOperatingLeaseRightOfUseAssets	-16787000	USD
CY2020	us-gaap	Increase Decrease In Accounts Payable And Accrued Liabilities IncreaseDecreaseInAccountsPayableAndAccruedLiabilities	-117931000	USD
CY2019	us-gaap	Increase Decrease In Accounts Payable And Accrued Liabilities IncreaseDecreaseInAccountsPayableAndAccruedLiabilities	27740000	USD
CY2018	us-gaap	Increase Decrease In Accounts Payable And Accrued Liabilities IncreaseDecreaseInAccountsPayableAndAccruedLiabilities	85798000	USD
CY2020	us-gaap	Increase Decrease In Contract With Customer Liability IncreaseDecreaseInContractWithCustomerLiability	2519000	USD
CY2019	us-gaap	Increase Decrease In Contract With Customer Liability IncreaseDecreaseInContractWithCustomerLiability	16480000	USD
CY2018	us-gaap	Increase Decrease In Contract With Customer Liability IncreaseDecreaseInContractWithCustomerLiability	-19344000	USD
CY2020	cien	Increase Decrease In Operating Lease Liability IncreaseDecreaseInOperatingLeaseLiability	-19896000	USD
CY2020	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	493654000	USD
CY2019	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	413140000	USD
CY2018	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	229261000	USD
CY2020	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	82667000	USD
CY2019	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	62579000	USD
CY2018	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	67616000	USD
CY2020	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	223196000	USD
CY2019	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	158074000	USD
CY2018	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	286824000	USD
CY2020	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	110390000	USD
CY2019	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	248748000	USD
CY2018	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	410109000	USD
CY2020	cien	Payments To Acquire Equity Securities Without Readily Determinable Fair Value PaymentsToAcquireEquitySecuritiesWithoutReadilyDeterminableFairValue	0	USD
CY2019	cien	Payments To Acquire Equity Securities Without Readily Determinable Fair Value PaymentsToAcquireEquitySecuritiesWithoutReadilyDeterminableFairValue	2667000	USD
CY2018	cien	Payments To Acquire Equity Securities Without Readily Determinable Fair Value PaymentsToAcquireEquitySecuritiesWithoutReadilyDeterminableFairValue	1767000	USD
CY2020	us-gaap	Payments For Proceeds From Derivative Instrument Investing Activities PaymentsForProceedsFromDerivativeInstrumentInvestingActivities	-3531000	USD
CY2019	us-gaap	Payments For Proceeds From Derivative Instrument Investing Activities PaymentsForProceedsFromDerivativeInstrumentInvestingActivities	1351000	USD
CY2018	us-gaap	Payments For Proceeds From Derivative Instrument Investing Activities PaymentsForProceedsFromDerivativeInstrumentInvestingActivities	-9385000	USD
CY2020	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	28300000	USD
CY2019	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	0	USD
CY2018	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	82670000	USD
CY2020	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-220242000	USD
CY2019	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	24077000	USD
CY2018	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-19383000	USD
CY2020	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	0	USD
CY2019	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	0	USD
CY2018	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	305125000	USD
CY2020	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	5198000	USD
CY2019	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	7000000	USD
CY2018	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	292730000	USD
CY2020	cien	Repaymentsof Convertible Debt Embedded Derivative RepaymentsofConvertibleDebtEmbeddedDerivative	0	USD
CY2019	cien	Repaymentsof Convertible Debt Embedded Derivative RepaymentsofConvertibleDebtEmbeddedDerivative	111268000	USD
CY2018	cien	Repaymentsof Convertible Debt Embedded Derivative RepaymentsofConvertibleDebtEmbeddedDerivative	0	USD
CY2020	cien	Paymentsfor Make Whole Provisionof Convertible Debt PaymentsforMakeWholeProvisionofConvertibleDebt	0	USD
CY2019	cien	Paymentsfor Make Whole Provisionof Convertible Debt PaymentsforMakeWholeProvisionofConvertibleDebt	0	USD
CY2018	cien	Paymentsfor Make Whole Provisionof Convertible Debt PaymentsforMakeWholeProvisionofConvertibleDebt	13453000	USD
CY2020	us-gaap	Payments Of Debt Issuance Costs PaymentsOfDebtIssuanceCosts	382000	USD
CY2019	us-gaap	Payments Of Debt Issuance Costs PaymentsOfDebtIssuanceCosts	1191000	USD
CY2018	us-gaap	Payments Of Debt Issuance Costs PaymentsOfDebtIssuanceCosts	1936000	USD
CY2020	us-gaap	Finance Lease Principal Payments FinanceLeasePrincipalPayments	2703000	USD
CY2019	us-gaap	Repayments Of Long Term Capital Lease Obligations RepaymentsOfLongTermCapitalLeaseObligations	3319000	USD
CY2018	us-gaap	Repayments Of Long Term Capital Lease Obligations RepaymentsOfLongTermCapitalLeaseObligations	3624000	USD
CY2020	us-gaap	Payments Related To Tax Withholding For Share Based Compensation PaymentsRelatedToTaxWithholdingForShareBasedCompensation	32472000	USD
CY2019	us-gaap	Payments Related To Tax Withholding For Share Based Compensation PaymentsRelatedToTaxWithholdingForShareBasedCompensation	29059000	USD
CY2018	us-gaap	Payments Related To Tax Withholding For Share Based Compensation PaymentsRelatedToTaxWithholdingForShareBasedCompensation	4757000	USD
CY2020	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	74535000	USD
CY2019	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	150076000	USD
CY2018	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	110981000	USD
CY2020	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	28068000	USD
CY2019	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	22947000	USD
CY2018	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	23127000	USD
CY2020	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-87222000	USD
CY2019	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-278966000	USD
CY2018	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-99229000	USD
CY2020	us-gaap	Effect Of Exchange Rate On Cash And Cash Equivalents EffectOfExchangeRateOnCashAndCashEquivalents	-1643000	USD
CY2019	us-gaap	Effect Of Exchange Rate On Cash And Cash Equivalents EffectOfExchangeRateOnCashAndCashEquivalents	476000	USD
CY2018	us-gaap	Effect Of Exchange Rate On Cash And Cash Equivalents EffectOfExchangeRateOnCashAndCashEquivalents	-5856000	USD
CY2020	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	184547000	USD
CY2019	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	158727000	USD
CY2018	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	104793000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	904161000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	745434000	USD
CY2017Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	640641000	USD
CY2020Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	1088708000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	904161000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	745434000	USD
CY2020	us-gaap	Interest Paid Net InterestPaidNet	32837000	USD
CY2019	us-gaap	Interest Paid Net InterestPaidNet	39579000	USD
CY2018	us-gaap	Interest Paid Net InterestPaidNet	44750000	USD
CY2020	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	53076000	USD
CY2019	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	33570000	USD
CY2018	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	26900000	USD
CY2020	us-gaap	Operating Lease Payments OperatingLeasePayments	22089000	USD
CY2020	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	7854000	USD
CY2019	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	16549000	USD
CY2018	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	5118000	USD
CY2020	cien	Noncashor Part Noncash Acquisition Contingent Consideration NoncashorPartNoncashAcquisitionContingentConsideration	0	USD
CY2019	cien	Noncashor Part Noncash Acquisition Contingent Consideration NoncashorPartNoncashAcquisitionContingentConsideration	0	USD
CY2018	cien	Noncashor Part Noncash Acquisition Contingent Consideration NoncashorPartNoncashAcquisitionContingentConsideration	10900000	USD
CY2020	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	24160000	USD
CY2020	us-gaap	Equity Securities Without Readily Determinable Fair Value Upward Price Adjustment Annual Amount EquitySecuritiesWithoutReadilyDeterminableFairValueUpwardPriceAdjustmentAnnualAmount	2681000	USD
CY2019	us-gaap	Equity Securities Without Readily Determinable Fair Value Upward Price Adjustment Annual Amount EquitySecuritiesWithoutReadilyDeterminableFairValueUpwardPriceAdjustmentAnnualAmount	0	USD
CY2018	us-gaap	Equity Securities Without Readily Determinable Fair Value Upward Price Adjustment Annual Amount EquitySecuritiesWithoutReadilyDeterminableFairValueUpwardPriceAdjustmentAnnualAmount	0	USD
CY2020	us-gaap	Fiscal Period FiscalPeriod	Ciena has a 52 or 53-week fiscal year, which ends on the Saturday nearest to the last day of October in each year. Fiscal 2020 and fiscal 2019 each consisted of a 52-week fiscal year and fiscal 2018 consisted of a 53-week fiscal year. Effective the second quarter of fiscal 2020, Ciena changed the presentation of reporting for its financial statements and notes thereto to reflect the actual dates on which fiscal years ended. Because these dates can change from period to period, for consistency purposes, Ciena previously presented such information indicating that its fiscal years ended on October 31. This change, affecting only the presentation of such information, was made on a prospective basis and it does not impact comparability of previous financial results. Reference to prior reported periods have been changed to reflect the actual period end dates of November 2, 2019, November 3, 2018 and October 28, 2017 for periods reported herein.
CY2020	us-gaap	Use Of Estimates UseOfEstimates	The preparation of the financial statements and related disclosures in conformity with Generally Accepted Accounting Principles (“GAAP”) requires management to make estimates and judgments that affect the amounts reported in the consolidated financial statements and accompanying notes. Estimates are used for selling prices for multiple element arrangements, shared-based compensation, bad debts, valuation of inventories and investments, recoverability of intangible assets, other long-lived assets and goodwill, income taxes, warranty obligations, restructuring liabilities, derivatives, contingencies and litigation. Ciena bases its estimates on historical experience and assumptions that it believes are reasonable. Actual results may differ materially from management’s estimates.
CY2020Q4	us-gaap	Equity Securities Without Readily Determinable Fair Value Amount EquitySecuritiesWithoutReadilyDeterminableFairValueAmount	13400000	USD
CY2020	us-gaap	Finite Lived Intangible Asset Useful Life FiniteLivedIntangibleAssetUsefulLife	P7Y
CY2020	cien	Maintenance Spare Parts Amortization Period MaintenanceSparePartsAmortizationPeriod	P4Y
CY2020Q4	us-gaap	Undistributed Earnings Of Foreign Subsidiaries UndistributedEarningsOfForeignSubsidiaries	375000000.0	USD
CY2020	cien	One Time Employee Termination Benefits Related Service Period OneTimeEmployeeTerminationBenefitsRelatedServicePeriod	P60D
CY2019Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	53300000	USD
CY2019Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	76000000.0	USD
CY2019Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	53334000	USD
CY2019Q4	us-gaap	Assets Assets	3893346000	USD
CY2019Q4	us-gaap	Assets Assets	3946680000	USD
CY2019Q4	us-gaap	Accrued Liabilities Current AccruedLiabilitiesCurrent	382740000	USD
CY2019Q4	us-gaap	Accrued Liabilities Current AccruedLiabilitiesCurrent	381256000	USD
CY2019Q4	us-gaap	Operating Lease Liability Current OperatingLeaseLiabilityCurrent	20498000	USD
CY2019Q4	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	148747000	USD
CY2019Q4	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	127503000	USD
CY2019Q4	us-gaap	Operating Lease Liability Noncurrent OperatingLeaseLiabilityNoncurrent	55564000	USD
CY2019Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	3893346000	USD
CY2019Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	3946680000	USD
CY2020	us-gaap	Revenues Revenues	3532157000	USD
CY2020	us-gaap	Revenues Revenues	3532157000	USD
CY2019	us-gaap	Revenues Revenues	3572131000	USD
CY2019	us-gaap	Revenues Revenues	3572131000	USD
CY2020	us-gaap	Revenues Revenues	3532157000	USD
CY2019	us-gaap	Revenues Revenues	3572131000	USD
CY2020Q4	us-gaap	Accounts Receivable Net Current AccountsReceivableNetCurrent	719405000	USD
CY2019Q4	us-gaap	Accounts Receivable Net Current AccountsReceivableNetCurrent	724854000	USD
CY2020Q4	us-gaap	Contract With Customer Asset Net ContractWithCustomerAssetNet	85843000	USD
CY2019Q4	us-gaap	Contract With Customer Asset Net ContractWithCustomerAssetNet	84046000	USD
CY2020Q4	us-gaap	Contract With Customer Liability ContractWithCustomerLiability	158363000	USD
CY2019Q4	us-gaap	Contract With Customer Liability ContractWithCustomerLiability	156873000	USD
CY2020	us-gaap	Contract With Customer Liability Revenue Recognized ContractWithCustomerLiabilityRevenueRecognized	101900000	USD
CY2019	us-gaap	Contract With Customer Liability Revenue Recognized ContractWithCustomerLiabilityRevenueRecognized	95100000	USD
CY2020Q4	us-gaap	Capitalized Contract Cost Net CapitalizedContractCostNet	15300000	USD
CY2019Q4	us-gaap	Capitalized Contract Cost Net CapitalizedContractCostNet	15700000	USD
CY2020	us-gaap	Capitalized Contract Cost Amortization CapitalizedContractCostAmortization	22400000	USD
CY2019	us-gaap	Capitalized Contract Cost Amortization CapitalizedContractCostAmortization	18600000	USD
CY2020Q4	us-gaap	Revenue Remaining Performance Obligation RevenueRemainingPerformanceObligation	1000000000.0	USD
CY2020Q4	us-gaap	Revenue Remaining Performance Obligation Percentage RevenueRemainingPerformanceObligationPercentage	0.81
CY2020Q4	us-gaap	Revenue Remaining Performance Obligation Expected Timing Of Satisfaction Period1 RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1	P12M
CY2017Q4	us-gaap	Restructuring Reserve RestructuringReserve	2939000	USD
CY2018	us-gaap	Restructuring Charges RestructuringCharges	18743000	USD
CY2018	us-gaap	Payments For Restructuring PaymentsForRestructuring	17835000	USD
CY2018Q4	us-gaap	Restructuring Reserve RestructuringReserve	3847000	USD
CY2019	us-gaap	Restructuring Charges RestructuringCharges	24538000	USD
CY2019	us-gaap	Payments For Restructuring PaymentsForRestructuring	13242000	USD
CY2019Q4	us-gaap	Restructuring Reserve RestructuringReserve	15143000	USD
CY2020	us-gaap	Restructuring Charges RestructuringCharges	22652000	USD
CY2019	us-gaap	Embedded Derivative Gain Loss On Embedded Derivative Net EmbeddedDerivativeGainLossOnEmbeddedDerivativeNet	0	USD
CY2020	us-gaap	Payments For Restructuring PaymentsForRestructuring	23720000	USD
CY2020Q4	us-gaap	Restructuring Reserve RestructuringReserve	2915000	USD
CY2020Q4	us-gaap	Restructuring Reserve Current RestructuringReserveCurrent	2915000	USD
CY2020Q4	us-gaap	Restructuring Reserve Noncurrent RestructuringReserveNoncurrent	0	USD
CY2020	us-gaap	Interest Income Expense Nonoperating Net InterestIncomeExpenseNonoperatingNet	6860000	USD
CY2019	us-gaap	Interest Income Expense Nonoperating Net InterestIncomeExpenseNonoperatingNet	14410000	USD
CY2018	us-gaap	Interest Income Expense Nonoperating Net InterestIncomeExpenseNonoperatingNet	13703000	USD
CY2020	us-gaap	Gain Loss On Foreign Currency Derivative Instruments Not Designated As Hedging Instruments GainLossOnForeignCurrencyDerivativeInstrumentsNotDesignatedAsHedgingInstruments	5551000	USD
CY2019	us-gaap	Gain Loss On Foreign Currency Derivative Instruments Not Designated As Hedging Instruments GainLossOnForeignCurrencyDerivativeInstrumentsNotDesignatedAsHedgingInstruments	3000	USD
CY2018	us-gaap	Gain Loss On Foreign Currency Derivative Instruments Not Designated As Hedging Instruments GainLossOnForeignCurrencyDerivativeInstrumentsNotDesignatedAsHedgingInstruments	6791000	USD
CY2020	us-gaap	Foreign Currency Transaction Gain Loss Before Tax ForeignCurrencyTransactionGainLossBeforeTax	-13022000	USD
CY2019	us-gaap	Foreign Currency Transaction Gain Loss Before Tax ForeignCurrencyTransactionGainLossBeforeTax	-9800000	USD
CY2018	us-gaap	Foreign Currency Transaction Gain Loss Before Tax ForeignCurrencyTransactionGainLossBeforeTax	-19434000	USD
CY2020	us-gaap	Embedded Derivative Gain Loss On Embedded Derivative Net EmbeddedDerivativeGainLossOnEmbeddedDerivativeNet	0	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities Within One Year Fair Value AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue	150667000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsAmortizedCost	82252000	USD
CY2018	us-gaap	Embedded Derivative Gain Loss On Embedded Derivative Net EmbeddedDerivativeGainLossOnEmbeddedDerivativeNet	-12070000	USD
CY2020	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	1575000	USD
CY2019	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	-737000	USD
CY2018	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	-1019000	USD
CY2020	cien	Interest And Other Income Loss Net InterestAndOtherIncomeLossNet	964000	USD
CY2019	cien	Interest And Other Income Loss Net InterestAndOtherIncomeLossNet	3876000	USD
CY2018	cien	Interest And Other Income Loss Net InterestAndOtherIncomeLossNet	-12029000	USD
CY2020	us-gaap	Foreign Currency Transaction Gain Loss Before Tax ForeignCurrencyTransactionGainLossBeforeTax	-13000000.0	USD
CY2019	us-gaap	Foreign Currency Transaction Gain Loss Before Tax ForeignCurrencyTransactionGainLossBeforeTax	-9800000	USD
CY2018	us-gaap	Foreign Currency Transaction Gain Loss Before Tax ForeignCurrencyTransactionGainLossBeforeTax	-19400000	USD
CY2020	us-gaap	Gain Loss On Foreign Currency Derivative Instruments Not Designated As Hedging Instruments GainLossOnForeignCurrencyDerivativeInstrumentsNotDesignatedAsHedgingInstruments	5600000	USD
CY2018	us-gaap	Gain Loss On Foreign Currency Derivative Instruments Not Designated As Hedging Instruments GainLossOnForeignCurrencyDerivativeInstrumentsNotDesignatedAsHedgingInstruments	6800000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities Within One Year Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearAmortizedCost	150559000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue	82226000	USD
CY2020Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	232811000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	232893000	USD
CY2019	cien	Business Combination Contingent Consideration Arrangements Term BusinessCombinationContingentConsiderationArrangementsTerm	P3Y
CY2020Q4	us-gaap	Business Combination Contingent Consideration Liability BusinessCombinationContingentConsiderationLiability	0	USD
CY2017Q4	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	17580000	USD
CY2018	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	2700000	USD
CY2018	us-gaap	Allowance For Doubtful Accounts Receivable Write Offs AllowanceForDoubtfulAccountsReceivableWriteOffs	2902000	USD
CY2018Q4	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	17378000	USD
CY2018Q4	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	17378000	USD
CY2019	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	6740000	USD
CY2019	us-gaap	Allowance For Doubtful Accounts Receivable Write Offs AllowanceForDoubtfulAccountsReceivableWriteOffs	4017000	USD
CY2019Q4	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	20101000	USD
CY2019Q4	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	20101000	USD
CY2020	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	8855000	USD
CY2020	us-gaap	Allowance For Doubtful Accounts Receivable Write Offs AllowanceForDoubtfulAccountsReceivableWriteOffs	18358000	USD
CY2020Q4	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	10598000	USD
CY2020Q4	us-gaap	Inventory Raw Materials InventoryRawMaterials	119481000	USD
CY2019Q4	us-gaap	Inventory Raw Materials InventoryRawMaterials	99041000	USD
CY2020Q4	us-gaap	Inventory Work In Process InventoryWorkInProcess	13738000	USD
CY2019Q4	us-gaap	Inventory Work In Process InventoryWorkInProcess	13657000	USD
CY2020Q4	us-gaap	Inventory Finished Goods InventoryFinishedGoods	210050000	USD
CY2019Q4	us-gaap	Inventory Finished Goods InventoryFinishedGoods	226622000	USD
CY2020Q4	us-gaap	Other Inventory Capitalized Costs OtherInventoryCapitalizedCosts	40747000	USD
CY2019Q4	us-gaap	Other Inventory Capitalized Costs OtherInventoryCapitalizedCosts	53051000	USD
CY2020Q4	us-gaap	Inventory Gross InventoryGross	384016000	USD
CY2019Q4	us-gaap	Inventory Gross InventoryGross	392371000	USD
CY2020Q4	us-gaap	Inventory Valuation Reserves InventoryValuationReserves	39637000	USD
CY2019Q4	us-gaap	Inventory Valuation Reserves InventoryValuationReserves	47322000	USD
CY2020Q4	us-gaap	Inventory Net InventoryNet	344379000	USD
CY2019Q4	us-gaap	Inventory Net InventoryNet	345049000	USD
CY2020	us-gaap	Inventory Write Down InventoryWriteDown	24700000	USD
CY2019	us-gaap	Inventory Write Down InventoryWriteDown	28100000	USD
CY2018	us-gaap	Inventory Write Down InventoryWriteDown	30600000	USD
CY2017Q4	us-gaap	Inventory Valuation Reserves InventoryValuationReserves	51206000	USD
CY2018	us-gaap	Inventory Write Down InventoryWriteDown	30615000	USD
CY2018	cien	Inventory Valuation Reserves Disposals InventoryValuationReservesDisposals	30883000	USD
CY2018Q4	us-gaap	Inventory Valuation Reserves InventoryValuationReserves	50938000	USD
CY2018Q4	us-gaap	Inventory Valuation Reserves InventoryValuationReserves	50938000	USD
CY2019	us-gaap	Inventory Write Down InventoryWriteDown	28085000	USD
CY2019	cien	Inventory Valuation Reserves Disposals InventoryValuationReservesDisposals	31701000	USD
CY2019Q4	us-gaap	Inventory Valuation Reserves InventoryValuationReserves	47322000	USD
CY2019Q4	us-gaap	Inventory Valuation Reserves InventoryValuationReserves	47322000	USD
CY2020	us-gaap	Inventory Write Down InventoryWriteDown	24701000	USD
CY2020	cien	Inventory Valuation Reserves Disposals InventoryValuationReservesDisposals	32386000	USD
CY2020Q4	us-gaap	Inventory Valuation Reserves InventoryValuationReserves	39637000	USD
CY2020Q4	us-gaap	Prepaid Taxes PrepaidTaxes	72838000	USD
CY2019Q4	us-gaap	Prepaid Taxes PrepaidTaxes	84706000	USD
CY2020Q4	us-gaap	Other Prepaid Expense Current OtherPrepaidExpenseCurrent	70647000	USD
CY2019Q4	us-gaap	Other Prepaid Expense Current OtherPrepaidExpenseCurrent	48680000	USD
CY2020Q4	cien	Product Demonstration Equipment Net ProductDemonstrationEquipmentNet	44793000	USD
CY2019Q4	cien	Product Demonstration Equipment Net ProductDemonstrationEquipmentNet	38900000	USD
CY2020Q4	us-gaap	Nontrade Receivables Current NontradeReceivablesCurrent	21981000	USD
CY2019Q4	us-gaap	Nontrade Receivables Current NontradeReceivablesCurrent	28136000	USD
CY2020Q4	us-gaap	Deferred Costs Current DeferredCostsCurrent	604000	USD
CY2019Q4	us-gaap	Deferred Costs Current DeferredCostsCurrent	125000	USD
CY2020Q4	us-gaap	Derivative Assets Current DerivativeAssetsCurrent	82000	USD
CY2019Q4	us-gaap	Derivative Assets Current DerivativeAssetsCurrent	1570000	USD
CY2020Q4	us-gaap	Restricted Cash Current RestrictedCashCurrent	0	USD
CY2019Q4	us-gaap	Restricted Cash Current RestrictedCashCurrent	74000	USD
CY2020Q4	us-gaap	Prepaid Expense And Other Assets Current PrepaidExpenseAndOtherAssetsCurrent	308084000	USD
CY2019Q4	us-gaap	Prepaid Expense And Other Assets Current PrepaidExpenseAndOtherAssetsCurrent	297914000	USD
CY2020	cien	Depreciation Of Product Demonstration Equipment DepreciationOfProductDemonstrationEquipment	9000000.0	USD
CY2019	cien	Depreciation Of Product Demonstration Equipment DepreciationOfProductDemonstrationEquipment	8800000	USD
CY2018	cien	Depreciation Of Product Demonstration Equipment DepreciationOfProductDemonstrationEquipment	9000000.0	USD
CY2020Q4	us-gaap	Finance Lease Right Of Use Asset Before Accumulated Amortization FinanceLeaseRightOfUseAssetBeforeAccumulatedAmortization	70791000	USD
CY2020Q4	us-gaap	Property Plant And Equipment And Finance Lease Right Of Use Asset Before Accumulated Depreciation And Amortization PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetBeforeAccumulatedDepreciationAndAmortization	683429000	USD
CY2019Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	710398000	USD
CY2020Q4	us-gaap	Property Plant And Equipment And Finance Lease Right Of Use Asset Accumulated Depreciation And Amortization PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAccumulatedDepreciationAndAmortization	411052000	USD
CY2019Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	423514000	USD
CY2020Q4	us-gaap	Property Plant And Equipment And Finance Lease Right Of Use Asset After Accumulated Depreciation And Amortization PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAfterAccumulatedDepreciationAndAmortization	272377000	USD
CY2019Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	286884000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Gross FiniteLivedIntangibleAssetsGross	773950000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	677303000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	96647000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Gross FiniteLivedIntangibleAssetsGross	751472000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	638691000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	112781000	USD
CY2020	cien	Amortization Of Intangible Assets Excluding Amortization Included In Property Plant And Equipment AmortizationOfIntangibleAssetsExcludingAmortizationIncludedInPropertyPlantAndEquipment	38600000	USD
CY2019	cien	Amortization Of Intangible Assets Excluding Amortization Included In Property Plant And Equipment AmortizationOfIntangibleAssetsExcludingAmortizationIncludedInPropertyPlantAndEquipment	35100000	USD
CY2018	cien	Amortization Of Intangible Assets Excluding Amortization Included In Property Plant And Equipment AmortizationOfIntangibleAssetsExcludingAmortizationIncludedInPropertyPlantAndEquipment	25800000	USD
CY2020	us-gaap	Goodwill Acquired During Period GoodwillAcquiredDuringPeriod	13055000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Next Twelve Months FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths	35452000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Two FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo	29232000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Three FiniteLivedIntangibleAssetsAmortizationExpenseYearThree	14422000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Four FiniteLivedIntangibleAssetsAmortizationExpenseYearFour	11371000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Five FiniteLivedIntangibleAssetsAmortizationExpenseYearFive	6170000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	96647000	USD
CY2019Q4	us-gaap	Goodwill Goodwill	297937000	USD
CY2020	us-gaap	Goodwill Foreign Currency Translation Gain Loss GoodwillForeignCurrencyTranslationGainLoss	-145000	USD
CY2020	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	0	USD
CY2020Q4	us-gaap	Goodwill Goodwill	310847000	USD
CY2019Q4	cien	Maintenance Spares Inventory Net Non Current MaintenanceSparesInventoryNetNonCurrent	55482000	USD
CY2020Q4	us-gaap	Equity Securities Without Readily Determinable Fair Value Amount EquitySecuritiesWithoutReadilyDeterminableFairValueAmount	13408000	USD
CY2019Q4	us-gaap	Equity Securities Without Readily Determinable Fair Value Amount EquitySecuritiesWithoutReadilyDeterminableFairValueAmount	10727000	USD
CY2020Q4	us-gaap	Capitalized Contract Cost Net Noncurrent CapitalizedContractCostNetNoncurrent	4001000	USD
CY2019Q4	us-gaap	Capitalized Contract Cost Net Noncurrent CapitalizedContractCostNetNoncurrent	3994000	USD
CY2020Q4	us-gaap	Debt Issuance Costs Line Of Credit Arrangements Net DebtIssuanceCostsLineOfCreditArrangementsNet	1596000	USD
CY2019Q4	us-gaap	Debt Issuance Costs Line Of Credit Arrangements Net DebtIssuanceCostsLineOfCreditArrangementsNet	1609000	USD
CY2020Q4	us-gaap	Restricted Cash Noncurrent RestrictedCashNoncurrent	84000	USD
CY2019Q4	us-gaap	Restricted Cash Noncurrent RestrictedCashNoncurrent	42000	USD
CY2020Q4	us-gaap	Other Assets Miscellaneous Noncurrent OtherAssetsMiscellaneousNoncurrent	21664000	USD
CY2019Q4	us-gaap	Other Assets Miscellaneous Noncurrent OtherAssetsMiscellaneousNoncurrent	17132000	USD
CY2020Q4	us-gaap	Other Assets Noncurrent OtherAssetsNoncurrent	102830000	USD
CY2019Q4	us-gaap	Other Assets Noncurrent OtherAssetsNoncurrent	88986000	USD
CY2020Q4	us-gaap	Equity Securities Without Readily Determinable Fair Value Upward Price Adjustment Annual Amount EquitySecuritiesWithoutReadilyDeterminableFairValueUpwardPriceAdjustmentAnnualAmount	2700000	USD
CY2020	us-gaap	Product Warranty Accrual Payments ProductWarrantyAccrualPayments	21047000	USD
CY2020Q4	us-gaap	Accrued Salaries Current AccruedSalariesCurrent	135462000	USD
CY2019Q4	us-gaap	Accrued Salaries Current AccruedSalariesCurrent	182363000	USD
CY2020Q4	us-gaap	Product Warranty Accrual Classified Current ProductWarrantyAccrualClassifiedCurrent	49868000	USD
CY2019Q4	us-gaap	Product Warranty Accrual Classified Current ProductWarrantyAccrualClassifiedCurrent	48498000	USD
CY2020Q4	us-gaap	Accrued Vacation Current AccruedVacationCurrent	26945000	USD
CY2019Q4	us-gaap	Accrued Vacation Current AccruedVacationCurrent	22290000	USD
CY2020Q4	us-gaap	Finance Lease Liability Current FinanceLeaseLiabilityCurrent	2836000	USD
CY2019Q4	us-gaap	Capital Lease Obligations Current CapitalLeaseObligationsCurrent	2764000	USD
CY2020Q4	us-gaap	Interest Payable Current InterestPayableCurrent	672000	USD
CY2019Q4	us-gaap	Interest Payable Current InterestPayableCurrent	1007000	USD
CY2020Q4	us-gaap	Business Combination Contingent Consideration Liability BusinessCombinationContingentConsiderationLiability	0	USD
CY2019Q4	us-gaap	Business Combination Contingent Consideration Liability BusinessCombinationContingentConsiderationLiability	4372000	USD
CY2020Q4	us-gaap	Other Accrued Liabilities Current OtherAccruedLiabilitiesCurrent	118349000	USD
CY2020Q4	us-gaap	Product Warranty Accrual Classified Current ProductWarrantyAccrualClassifiedCurrent	49868000	USD
CY2019Q4	us-gaap	Other Accrued Liabilities Current OtherAccruedLiabilitiesCurrent	121446000	USD
CY2020Q4	us-gaap	Accrued Liabilities Current AccruedLiabilitiesCurrent	334132000	USD
CY2019Q4	us-gaap	Accrued Liabilities Current AccruedLiabilitiesCurrent	382740000	USD
CY2017Q4	us-gaap	Product Warranty Accrual Classified Current ProductWarrantyAccrualClassifiedCurrent	42456000	USD
CY2018	us-gaap	Product Warranty Expense ProductWarrantyExpense	20992000	USD
CY2018	us-gaap	Product Warranty Accrual Payments ProductWarrantyAccrualPayments	18708000	USD
CY2018Q4	us-gaap	Product Warranty Accrual Classified Current ProductWarrantyAccrualClassifiedCurrent	44740000	USD
CY2018Q4	us-gaap	Product Warranty Accrual Classified Current ProductWarrantyAccrualClassifiedCurrent	44740000	USD
CY2019	us-gaap	Product Warranty Expense ProductWarrantyExpense	23105000	USD
CY2019	us-gaap	Product Warranty Accrual Payments ProductWarrantyAccrualPayments	19347000	USD
CY2019Q4	us-gaap	Product Warranty Accrual Classified Current ProductWarrantyAccrualClassifiedCurrent	48498000	USD
CY2019Q4	us-gaap	Product Warranty Accrual Classified Current ProductWarrantyAccrualClassifiedCurrent	48498000	USD
CY2020	us-gaap	Product Warranty Expense ProductWarrantyExpense	22417000	USD
CY2019Q4	cien	Tenant Improvement Accrual Noncurrent TenantImprovementAccrualNoncurrent	6248000	USD
CY2019Q4	us-gaap	Deferred Rent Credit Noncurrent DeferredRentCreditNoncurrent	5434000	USD
CY2020Q4	us-gaap	Contract With Customer Liability ContractWithCustomerLiability	158363000	USD
CY2019Q4	us-gaap	Contract With Customer Liability ContractWithCustomerLiability	156873000	USD
CY2020Q4	us-gaap	Contract With Customer Liability Current ContractWithCustomerLiabilityCurrent	108700000	USD
CY2019Q4	us-gaap	Contract With Customer Liability Current ContractWithCustomerLiabilityCurrent	111381000	USD
CY2020Q4	us-gaap	Contract With Customer Liability Noncurrent ContractWithCustomerLiabilityNoncurrent	49663000	USD
CY2019Q4	us-gaap	Contract With Customer Liability Noncurrent ContractWithCustomerLiabilityNoncurrent	45492000	USD
CY2020Q4	us-gaap	Finance Lease Liability Noncurrent FinanceLeaseLiabilityNoncurrent	61565000	USD
CY2019Q4	us-gaap	Capital Lease Obligations Noncurrent CapitalLeaseObligationsNoncurrent	65284000	USD
CY2020Q4	us-gaap	Derivative Liabilities Noncurrent DerivativeLiabilitiesNoncurrent	28513000	USD
CY2019Q4	us-gaap	Derivative Liabilities Noncurrent DerivativeLiabilitiesNoncurrent	21093000	USD
CY2020Q4	us-gaap	Accrued Income Taxes Noncurrent AccruedIncomeTaxesNoncurrent	16386000	USD
CY2019Q4	us-gaap	Accrued Income Taxes Noncurrent AccruedIncomeTaxesNoncurrent	20546000	USD
CY2020Q4	cien	Tenant Improvement Accrual Noncurrent TenantImprovementAccrualNoncurrent	0	USD
CY2020	us-gaap	Reclassification From Aoci Current Period Net Of Tax Attributable To Parent ReclassificationFromAociCurrentPeriodNetOfTaxAttributableToParent	-7200000	USD
CY2020Q4	us-gaap	Interest Rate Cash Flow Hedge Liability At Fair Value InterestRateCashFlowHedgeLiabilityAtFairValue	0	USD
CY2019Q4	us-gaap	Interest Rate Cash Flow Hedge Liability At Fair Value InterestRateCashFlowHedgeLiabilityAtFairValue	3705000	USD
CY2020Q4	cien	Other Obligations Noncurrent OtherObligationsNoncurrent	16721000	USD
CY2019Q4	cien	Other Obligations Noncurrent OtherObligationsNoncurrent	26437000	USD
CY2020Q4	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	123185000	USD
CY2019Q4	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	148747000	USD
CY2018	us-gaap	Oci Before Reclassifications Net Of Tax Attributable To Parent OciBeforeReclassificationsNetOfTaxAttributableToParent	3481000	USD
CY2018	us-gaap	Reclassification From Aoci Current Period Net Of Tax Attributable To Parent ReclassificationFromAociCurrentPeriodNetOfTaxAttributableToParent	-1756000	USD
CY2019	us-gaap	Oci Before Reclassifications Net Of Tax Attributable To Parent OciBeforeReclassificationsNetOfTaxAttributableToParent	-19120000	USD
CY2019	us-gaap	Reclassification From Aoci Current Period Net Of Tax Attributable To Parent ReclassificationFromAociCurrentPeriodNetOfTaxAttributableToParent	-2816000	USD
CY2020	us-gaap	Oci Before Reclassifications Net Of Tax Attributable To Parent OciBeforeReclassificationsNetOfTaxAttributableToParent	-20474000	USD
CY2020Q4	cien	Lessee Operating Lease Areaof Property Leased LesseeOperatingLeaseAreaofPropertyLeased	1300000	sqft
CY2020	cien	Lease Remaining Lease Term LeaseRemainingLeaseTerm	P12Y
CY2020	cien	Lessee Lease Renewal Term LesseeLeaseRenewalTerm	P10Y
CY2020	cien	Lessee Lease Termination Period LesseeLeaseTerminationPeriod	P6Y
CY2020Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	57026000	USD
CY2020Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	80450000	USD
CY2020Q4	us-gaap	Finance Lease Right Of Use Asset Before Accumulated Amortization FinanceLeaseRightOfUseAssetBeforeAccumulatedAmortization	70791000	USD
CY2020Q4	us-gaap	Finance Lease Right Of Use Asset Accumulated Amortization FinanceLeaseRightOfUseAssetAccumulatedAmortization	17837000	USD
CY2020Q4	us-gaap	Finance Lease Right Of Use Asset FinanceLeaseRightOfUseAsset	52954000	USD
CY2020Q4	cien	Lessee Operating Lease Right Of Use Asset Subleased Or Vacant LesseeOperatingLeaseRightOfUseAssetSubleasedOrVacant	5000000.0	USD
CY2020	us-gaap	Operating Lease Cost OperatingLeaseCost	17544000	USD
CY2020	us-gaap	Finance Lease Right Of Use Asset Amortization FinanceLeaseRightOfUseAssetAmortization	4465000	USD
CY2020	us-gaap	Finance Lease Interest Expense FinanceLeaseInterestExpense	4777000	USD
CY2020	cien	Finance Lease Cost FinanceLeaseCost	9242000	USD
CY2020	us-gaap	Short Term Lease Cost ShortTermLeaseCost	2976000	USD
CY2020	us-gaap	Variable Lease Cost VariableLeaseCost	5185000	USD
CY2020	us-gaap	Lease Cost LeaseCost	34947000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Five LesseeOperatingLeaseLiabilityPaymentsDueYearFive	8838000	USD
CY2020Q4	us-gaap	Finance Lease Liability Payments Due Year Five FinanceLeaseLiabilityPaymentsDueYearFive	8118000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Next Twelve Months LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths	20989000	USD
CY2020Q4	us-gaap	Finance Lease Liability Payments Due Next Twelve Months FinanceLeaseLiabilityPaymentsDueNextTwelveMonths	7444000	USD
CY2020Q4	cien	Lease Liability Payment Due Year One LeaseLiabilityPaymentDueYearOne	28433000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Two LesseeOperatingLeaseLiabilityPaymentsDueYearTwo	18689000	USD
CY2020Q4	us-gaap	Finance Lease Liability Payments Due Year Two FinanceLeaseLiabilityPaymentsDueYearTwo	7754000	USD
CY2020Q4	cien	Lease Liability Payment Due Year Two LeaseLiabilityPaymentDueYearTwo	26443000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Three LesseeOperatingLeaseLiabilityPaymentsDueYearThree	15415000	USD
CY2020Q4	us-gaap	Finance Lease Liability Payments Due Year Three FinanceLeaseLiabilityPaymentsDueYearThree	7958000	USD
CY2020Q4	cien	Lease Liability Payment Due Year Three LeaseLiabilityPaymentDueYearThree	23373000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Four LesseeOperatingLeaseLiabilityPaymentsDueYearFour	13118000	USD
CY2020Q4	us-gaap	Finance Lease Liability Payments Due Year Four FinanceLeaseLiabilityPaymentsDueYearFour	7958000	USD
CY2020Q4	cien	Lease Liability Payment Due Year Four LeaseLiabilityPaymentDueYearFour	21076000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due After Year Five LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive	9365000	USD
CY2020Q4	us-gaap	Finance Lease Liability Payments Due After Year Five FinanceLeaseLiabilityPaymentsDueAfterYearFive	58101000	USD
CY2020Q4	cien	Lease Liability Payment Due After Year Five LeaseLiabilityPaymentDueAfterYearFive	67466000	USD
CY2020Q4	cien	Lease Liability Payment Due Year Five LeaseLiabilityPaymentDueYearFive	16956000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due LesseeOperatingLeaseLiabilityPaymentsDue	86414000	USD
CY2020Q4	us-gaap	Finance Lease Liability Payments Due FinanceLeaseLiabilityPaymentsDue	97333000	USD
CY2020Q4	cien	Lease Liability Payment Due LeaseLiabilityPaymentDue	183747000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Undiscounted Excess Amount LesseeOperatingLeaseLiabilityUndiscountedExcessAmount	5964000	USD
CY2020Q4	us-gaap	Finance Lease Liability Undiscounted Excess Amount FinanceLeaseLiabilityUndiscountedExcessAmount	32932000	USD
CY2020Q4	cien	Lease Liability Undiscounted Excess Amount LeaseLiabilityUndiscountedExcessAmount	38896000	USD
CY2020Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	80450000	USD
CY2020Q4	us-gaap	Finance Lease Liability FinanceLeaseLiability	64401000	USD
CY2020Q4	cien	Lease Liability LeaseLiability	144851000	USD
CY2020Q4	us-gaap	Operating Lease Liability Current OperatingLeaseLiabilityCurrent	19035000	USD
CY2020Q4	us-gaap	Finance Lease Liability Current FinanceLeaseLiabilityCurrent	2836000	USD
CY2020Q4	cien	Lease Liability Current LeaseLiabilityCurrent	21871000	USD
CY2020Q4	us-gaap	Operating Lease Liability Noncurrent OperatingLeaseLiabilityNoncurrent	61415000	USD
CY2020Q4	us-gaap	Finance Lease Liability Noncurrent FinanceLeaseLiabilityNoncurrent	61565000	USD
CY2020Q4	cien	Lease Liability Noncurrent LeaseLiabilityNoncurrent	122980000	USD
CY2020Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P4Y10M13D
CY2020Q4	us-gaap	Finance Lease Weighted Average Remaining Lease Term1 FinanceLeaseWeightedAverageRemainingLeaseTerm1	P11Y8M15D
CY2020Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.0282
CY2020Q4	us-gaap	Finance Lease Weighted Average Discount Rate Percent FinanceLeaseWeightedAverageDiscountRatePercent	0.0756
CY2019Q4	us-gaap	Operating Leases Future Minimum Payments Due Current OperatingLeasesFutureMinimumPaymentsDueCurrent	28776000	USD
CY2019Q4	us-gaap	Operating Leases Future Minimum Payments Due In Two Years OperatingLeasesFutureMinimumPaymentsDueInTwoYears	24184000	USD
CY2019Q4	us-gaap	Operating Leases Future Minimum Payments Due In Three Years OperatingLeasesFutureMinimumPaymentsDueInThreeYears	16767000	USD
CY2019Q4	us-gaap	Operating Leases Future Minimum Payments Due In Four Years OperatingLeasesFutureMinimumPaymentsDueInFourYears	13393000	USD
CY2019Q4	us-gaap	Operating Leases Future Minimum Payments Due In Five Years OperatingLeasesFutureMinimumPaymentsDueInFiveYears	10632000	USD
CY2019Q4	us-gaap	Operating Leases Future Minimum Payments Due Thereafter OperatingLeasesFutureMinimumPaymentsDueThereafter	26110000	USD
CY2019Q4	us-gaap	Operating Leases Future Minimum Payments Due OperatingLeasesFutureMinimumPaymentsDue	119862000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	361291000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	253434000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	-344690000	USD
CY2020	cien	Dilutive Gain Losson Embedded Derivative Net DilutiveGainLossonEmbeddedDerivativeNet	0	USD
CY2019	cien	Dilutive Gain Losson Embedded Derivative Net DilutiveGainLossonEmbeddedDerivativeNet	0	USD
CY2018	cien	Dilutive Gain Losson Embedded Derivative Net DilutiveGainLossonEmbeddedDerivativeNet	-12894000	USD
CY2020	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	361291000	USD
CY2019	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	253434000	USD
CY2018	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	-357584000	USD
CY2020	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	154287000	shares
CY2019	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	155720000	shares
CY2018	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	143738000	shares
CY2020	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	1668000	shares
CY2019	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	1892000	shares
CY2018	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	0	shares
CY2018Q4	us-gaap	Stock Repurchase Program Authorized Amount1 StockRepurchaseProgramAuthorizedAmount1	500000000	USD
CY2020	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	155955000	shares
CY2019	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	157612000	shares
CY2018	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	143738000	shares
CY2020	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.34
CY2019	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.63
CY2018	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	-2.40
CY2020	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.32
CY2019	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.61
CY2018	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	-2.49
CY2020	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	263000	shares
CY2019	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	234000	shares
CY2018	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	16021000	shares
CY2018Q4	cien	Cumulative Shares Repurchased Excluding Shares Purchasedfor Tax Withholdingsfor Sharebased Compensation Shares CumulativeSharesRepurchasedExcludingSharesPurchasedforTaxWithholdingsforSharebasedCompensationShares	0	shares
CY2018Q4	cien	Cumulative Shares Repurchased Excluding Shares Purchasedfor Tax Withholdingsfor Sharebased Compensation Weighted Average Price Per Share CumulativeSharesRepurchasedExcludingSharesPurchasedforTaxWithholdingsforSharebasedCompensationWeightedAveragePricePerShare	0
CY2018Q4	cien	Cumulative Shares Repurchased Excluding Shares Purchasedfor Tax Withholdingsfor Sharebased Compensation Value CumulativeSharesRepurchasedExcludingSharesPurchasedforTaxWithholdingsforSharebasedCompensationValue	0	USD
CY2019	us-gaap	Stock Repurchased During Period Shares StockRepurchasedDuringPeriodShares	3838466000	shares
CY2019	cien	Shares Repurchased During Period Weighted Average Price Per Share SharesRepurchasedDuringPeriodWeightedAveragePricePerShare	39.10
CY2019	us-gaap	Stock Repurchased During Period Value StockRepurchasedDuringPeriodValue	150076000	USD
CY2019Q4	cien	Cumulative Shares Repurchased Excluding Shares Purchasedfor Tax Withholdingsfor Sharebased Compensation Shares CumulativeSharesRepurchasedExcludingSharesPurchasedforTaxWithholdingsforSharebasedCompensationShares	3838466000	shares
CY2019Q4	cien	Cumulative Shares Repurchased Excluding Shares Purchasedfor Tax Withholdingsfor Sharebased Compensation Weighted Average Price Per Share CumulativeSharesRepurchasedExcludingSharesPurchasedforTaxWithholdingsforSharebasedCompensationWeightedAveragePricePerShare	39.10
CY2019Q4	cien	Cumulative Shares Repurchased Excluding Shares Purchasedfor Tax Withholdingsfor Sharebased Compensation Value CumulativeSharesRepurchasedExcludingSharesPurchasedforTaxWithholdingsforSharebasedCompensationValue	150076000	USD
CY2020	us-gaap	Stock Repurchased During Period Shares StockRepurchasedDuringPeriodShares	1872446000	shares
CY2020	cien	Shares Repurchased During Period Weighted Average Price Per Share SharesRepurchasedDuringPeriodWeightedAveragePricePerShare	39.81
CY2020	us-gaap	Stock Repurchased During Period Value StockRepurchasedDuringPeriodValue	74535000	USD
CY2020Q4	cien	Cumulative Shares Repurchased Excluding Shares Purchasedfor Tax Withholdingsfor Sharebased Compensation Shares CumulativeSharesRepurchasedExcludingSharesPurchasedforTaxWithholdingsforSharebasedCompensationShares	5710912000	shares
CY2020	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	60679000	USD
CY2019	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	31872000	USD
CY2020Q4	cien	Cumulative Shares Repurchased Excluding Shares Purchasedfor Tax Withholdingsfor Sharebased Compensation Weighted Average Price Per Share CumulativeSharesRepurchasedExcludingSharesPurchasedforTaxWithholdingsforSharebasedCompensationWeightedAveragePricePerShare	39.33
CY2020Q4	cien	Cumulative Shares Repurchased Excluding Shares Purchasedfor Tax Withholdingsfor Sharebased Compensation Value CumulativeSharesRepurchasedExcludingSharesPurchasedforTaxWithholdingsforSharebasedCompensationValue	224611000	USD
CY2020	us-gaap	Payments Related To Tax Withholding For Share Based Compensation PaymentsRelatedToTaxWithholdingForShareBasedCompensation	32500000	USD
CY2020	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	4363000	USD
CY2019	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	13143000	USD
CY2018	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	8327000	USD
CY2020	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	13328000	USD
CY2019	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	16945000	USD
CY2018	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	8219000	USD
CY2020	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	12640000	USD
CY2019	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	9816000	USD
CY2018	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	13294000	USD
CY2020	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	30331000	USD
CY2019	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	39904000	USD
CY2018	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	29840000	USD
CY2018	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	475951000	USD
CY2020	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	4607000	USD
CY2019	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	-9159000	USD
CY2018	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	-8202000	USD
CY2020	us-gaap	Deferred Foreign Income Tax Expense Benefit DeferredForeignIncomeTaxExpenseBenefit	-947000	USD
CY2019	us-gaap	Deferred Foreign Income Tax Expense Benefit DeferredForeignIncomeTaxExpenseBenefit	-2861000	USD
CY2018	us-gaap	Deferred Foreign Income Tax Expense Benefit DeferredForeignIncomeTaxExpenseBenefit	-4118000	USD
CY2020	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	64339000	USD
CY2019	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	19852000	USD
CY2018	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	463631000	USD
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	94670000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	59756000	USD
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	493471000	USD
CY2020	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	387697000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	256461000	USD
CY2018	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	106972000	USD
CY2020	us-gaap	Income Loss From Continuing Operations Before Income Taxes Foreign IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign	68264000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Before Income Taxes Foreign IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign	56729000	USD
CY2018	us-gaap	Income Loss From Continuing Operations Before Income Taxes Foreign IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign	41809000	USD
CY2020	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	455961000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	313190000	USD
CY2018	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	148781000	USD
CY2020	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.2100
CY2019	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.2100
CY2018	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.2341
CY2020	cien	Effective Income Tax Rate Reconciliation Changein Tax Rate Deferred Tax Asset Tax Cutsand Jobs Act Percent EffectiveIncomeTaxRateReconciliationChangeinTaxRateDeferredTaxAssetTaxCutsandJobsActPercent	0
CY2019	cien	Effective Income Tax Rate Reconciliation Changein Tax Rate Deferred Tax Asset Tax Cutsand Jobs Act Percent EffectiveIncomeTaxRateReconciliationChangeinTaxRateDeferredTaxAssetTaxCutsandJobsActPercent	0
CY2018	cien	Effective Income Tax Rate Reconciliation Changein Tax Rate Deferred Tax Asset Tax Cutsand Jobs Act Percent EffectiveIncomeTaxRateReconciliationChangeinTaxRateDeferredTaxAssetTaxCutsandJobsActPercent	2.9456
CY2020	cien	Effective Income Tax Rate Reconciliation Base Erosionand Anti Abuse Tax Percent EffectiveIncomeTaxRateReconciliationBaseErosionandAntiAbuseTaxPercent	-0.0102
CY2019	cien	Effective Income Tax Rate Reconciliation Base Erosionand Anti Abuse Tax Percent EffectiveIncomeTaxRateReconciliationBaseErosionandAntiAbuseTaxPercent	0.0360
CY2018	cien	Effective Income Tax Rate Reconciliation Base Erosionand Anti Abuse Tax Percent EffectiveIncomeTaxRateReconciliationBaseErosionandAntiAbuseTaxPercent	0
CY2020	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	0.0221
CY2019	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	0.0218
CY2018	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	-0.0016
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Foreign Income Tax Rate Differential EffectiveIncomeTaxRateReconciliationForeignIncomeTaxRateDifferential	0.0051
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Foreign Income Tax Rate Differential EffectiveIncomeTaxRateReconciliationForeignIncomeTaxRateDifferential	-0.0037
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Foreign Income Tax Rate Differential EffectiveIncomeTaxRateReconciliationForeignIncomeTaxRateDifferential	0.0122
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Tax Credits Research EffectiveIncomeTaxRateReconciliationTaxCreditsResearch	0.0774
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Tax Credits Research EffectiveIncomeTaxRateReconciliationTaxCreditsResearch	0.0753
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Tax Credits Research EffectiveIncomeTaxRateReconciliationTaxCreditsResearch	0.0880
CY2020	cien	Effective Income Tax Rate Reconciliation Nondeductible Expense Share Based Compensation Cost And Other EffectiveIncomeTaxRateReconciliationNondeductibleExpenseShareBasedCompensationCostAndOther	0.0179
CY2019	cien	Effective Income Tax Rate Reconciliation Nondeductible Expense Share Based Compensation Cost And Other EffectiveIncomeTaxRateReconciliationNondeductibleExpenseShareBasedCompensationCostAndOther	0.0101
CY2018	cien	Effective Income Tax Rate Reconciliation Nondeductible Expense Share Based Compensation Cost And Other EffectiveIncomeTaxRateReconciliationNondeductibleExpenseShareBasedCompensationCostAndOther	0.0339
CY2020	cien	Effective Income Tax Rate Reconciliation Embedded Derivative Percent EffectiveIncomeTaxRateReconciliationEmbeddedDerivativePercent	0
CY2019	cien	Effective Income Tax Rate Reconciliation Embedded Derivative Percent EffectiveIncomeTaxRateReconciliationEmbeddedDerivativePercent	0
CY2018	cien	Effective Income Tax Rate Reconciliation Embedded Derivative Percent EffectiveIncomeTaxRateReconciliationEmbeddedDerivativePercent	0.0190
CY2020	cien	Effective Income Tax Rate Reconciliation Tax Cutsand Jobs Act Transition Taxon Accumulated Foreign Earnings Percent EffectiveIncomeTaxRateReconciliationTaxCutsandJobsActTransitionTaxonAccumulatedForeignEarningsPercent	0.0002
CY2019	cien	Effective Income Tax Rate Reconciliation Tax Cutsand Jobs Act Transition Taxon Accumulated Foreign Earnings Percent EffectiveIncomeTaxRateReconciliationTaxCutsandJobsActTransitionTaxonAccumulatedForeignEarningsPercent	0.0029
CY2018	cien	Effective Income Tax Rate Reconciliation Tax Cutsand Jobs Act Transition Taxon Accumulated Foreign Earnings Percent EffectiveIncomeTaxRateReconciliationTaxCutsandJobsActTransitionTaxonAccumulatedForeignEarningsPercent	0.2323
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Change In Deferred Tax Assets Valuation Allowance EffectiveIncomeTaxRateReconciliationChangeInDeferredTaxAssetsValuationAllowance	0.0358
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Change In Deferred Tax Assets Valuation Allowance EffectiveIncomeTaxRateReconciliationChangeInDeferredTaxAssetsValuationAllowance	-0.0213
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Change In Deferred Tax Assets Valuation Allowance EffectiveIncomeTaxRateReconciliationChangeInDeferredTaxAssetsValuationAllowance	-0.1195
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Other Reconciling Items Percent EffectiveIncomeTaxRateReconciliationOtherReconcilingItemsPercent	0.0041
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Other Reconciling Items Percent EffectiveIncomeTaxRateReconciliationOtherReconcilingItemsPercent	0.0103
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Other Reconciling Items Percent EffectiveIncomeTaxRateReconciliationOtherReconcilingItemsPercent	0.0488
CY2020	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.2076
CY2019	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.1908
CY2018	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	3.3168
CY2018	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.2341
CY2019	us-gaap	Tax Cuts And Jobs Act Of2017 Income Tax Expense Benefit TaxCutsAndJobsActOf2017IncomeTaxExpenseBenefit	472800000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals DeferredTaxAssetsTaxDeferredExpenseReservesAndAccruals	73825000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals DeferredTaxAssetsTaxDeferredExpenseReservesAndAccruals	54183000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Other DeferredTaxAssetsTaxDeferredExpenseOther	504233000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Other DeferredTaxAssetsTaxDeferredExpenseOther	455007000	USD
CY2020Q4	cien	Deferred Tax Asset Operating Loss And Tax Credit Carryforwards DeferredTaxAssetOperatingLossAndTaxCreditCarryforwards	188157000	USD
CY2019Q4	cien	Deferred Tax Asset Operating Loss And Tax Credit Carryforwards DeferredTaxAssetOperatingLossAndTaxCreditCarryforwards	302325000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	33017000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	39405000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	799232000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	850920000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	151427000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	135978000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	647805000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	714942000	USD
CY2017Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	141582000	USD
CY2018	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions	46400000	USD
CY2018	us-gaap	Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions	2482000	USD
CY2018	us-gaap	Unrecognized Tax Benefits Reductions Resulting From Lapse Of Applicable Statute Of Limitations UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitations	1301000	USD
CY2018Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	96363000	USD
CY2019	us-gaap	Unrecognized Tax Benefits Increases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions	1959000	USD
CY2019	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Settlements With Taxing Authorities UnrecognizedTaxBenefitsDecreasesResultingFromSettlementsWithTaxingAuthorities	1224000	USD
CY2019	us-gaap	Unrecognized Tax Benefits Reductions Resulting From Lapse Of Applicable Statute Of Limitations UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitations	2494000	USD
CY2019Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	94604000	USD
CY2020	us-gaap	Unrecognized Tax Benefits Increases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions	653000	USD
CY2020	us-gaap	Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions	1151000	USD
CY2020	us-gaap	Unrecognized Tax Benefits Reductions Resulting From Lapse Of Applicable Statute Of Limitations UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitations	660000	USD
CY2020Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	95748000	USD
CY2020Q4	us-gaap	Unrecognized Tax Benefits Income Tax Penalties And Interest Accrued UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued	3900000	USD
CY2019Q4	us-gaap	Unrecognized Tax Benefits Income Tax Penalties And Interest Accrued UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued	3000000.0	USD
CY2020	us-gaap	Income Tax Examination Penalties And Interest Expense IncomeTaxExaminationPenaltiesAndInterestExpense	900000	USD
CY2018	us-gaap	Income Tax Examination Penalties And Interest Expense IncomeTaxExaminationPenaltiesAndInterestExpense	1100000	USD
CY2019	us-gaap	Income Tax Examination Penalties And Interest Expense IncomeTaxExaminationPenaltiesAndInterestExpense	1000000.0	USD
CY2020Q4	us-gaap	Undistributed Earnings Of Foreign Subsidiaries UndistributedEarningsOfForeignSubsidiaries	375000000.0	USD
CY2020Q4	us-gaap	Deferred Tax Liability Not Recognized Amount Of Unrecognized Deferred Tax Liability Undistributed Earnings Of Foreign Subsidiaries DeferredTaxLiabilityNotRecognizedAmountOfUnrecognizedDeferredTaxLiabilityUndistributedEarningsOfForeignSubsidiaries	25000000.0	USD
CY2020Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	151400000	USD
CY2017Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	185898000	USD
CY2018	cien	Valuation Allowance Deferred Tax Asset Additions ValuationAllowanceDeferredTaxAssetAdditions	23720000	USD
CY2018	cien	Valuation Allowance Deferred Tax Asset Deductions ValuationAllowanceDeferredTaxAssetDeductions	66968000	USD
CY2018Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	142650000	USD
CY2018Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	142650000	USD
CY2019	cien	Valuation Allowance Deferred Tax Asset Additions ValuationAllowanceDeferredTaxAssetAdditions	27459000	USD
CY2019	cien	Valuation Allowance Deferred Tax Asset Deductions ValuationAllowanceDeferredTaxAssetDeductions	34131000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	135978000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	135978000	USD
CY2020	cien	Valuation Allowance Deferred Tax Asset Additions ValuationAllowanceDeferredTaxAssetAdditions	25749000	USD
CY2020	cien	Valuation Allowance Deferred Tax Asset Deductions ValuationAllowanceDeferredTaxAssetDeductions	10300000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	151427000	USD
CY2020Q4	us-gaap	Tax Credit Carryforward Amount TaxCreditCarryforwardAmount	38200000	USD
CY2019	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriod	0	shares
CY2018	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriod	0	shares
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriod	0	shares
CY2019Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber	220000	shares
CY2019Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice	35.54
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriod	0	shares
CY2020	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Grants In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice	0
CY2020	us-gaap	Stock Issued During Period Shares Stock Options Exercised StockIssuedDuringPeriodSharesStockOptionsExercised	105000	shares
CY2020	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Exercises In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice	40.27
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Forfeitures In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresInPeriod	8000	shares
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Forfeitures And Expirations In Period Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriodWeightedAverageExercisePrice	28.22
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber	107000	shares
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice	31.41
CY2020	us-gaap	Employee Service Share Based Compensation Allocation Of Recognized Period Costs Capitalized Amount EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsCapitalizedAmount	118000	USD
CY2019	us-gaap	Employee Service Share Based Compensation Allocation Of Recognized Period Costs Capitalized Amount EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsCapitalizedAmount	57000	USD
CY2018	us-gaap	Employee Service Share Based Compensation Allocation Of Recognized Period Costs Capitalized Amount EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsCapitalizedAmount	-101000	USD
CY2020	us-gaap	Share Based Compensation ShareBasedCompensation	67758000	USD
CY2019	us-gaap	Share Based Compensation ShareBasedCompensation	59736000	USD
CY2018	us-gaap	Share Based Compensation ShareBasedCompensation	52972000	USD
CY2020Q4	us-gaap	Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized	111900000	USD
CY2020Q4	us-gaap	Property Plant And Equipment And Finance Lease Right Of Use Asset After Accumulated Depreciation And Amortization PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAfterAccumulatedDepreciationAndAmortization	272400000	USD
CY2020Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	57000000.0	USD
CY2020	us-gaap	Number Of Operating Segments NumberOfOperatingSegments	4	segment
CY2020Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	96647000	USD
CY2020Q4	us-gaap	Goodwill Goodwill	310847000	USD
CY2020Q4	cien	Maintenance Spares Inventory Net Non Current MaintenanceSparesInventoryNetNonCurrent	62077000	USD
CY2020	us-gaap	Selling And Marketing Expense SellingAndMarketingExpense	416425000	USD
CY2019	us-gaap	Selling And Marketing Expense SellingAndMarketingExpense	423046000	USD
CY2018	us-gaap	Selling And Marketing Expense SellingAndMarketingExpense	394060000	USD
CY2020	us-gaap	General And Administrative Expense GeneralAndAdministrativeExpense	169548000	USD
CY2019	us-gaap	General And Administrative Expense GeneralAndAdministrativeExpense	174399000	USD
CY2018	us-gaap	General And Administrative Expense GeneralAndAdministrativeExpense	160133000	USD
CY2020	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	23383000	USD
CY2019	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	21808000	USD
CY2018	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	15737000	USD
CY2020	us-gaap	Business Combination Acquisition Related Costs BusinessCombinationAcquisitionRelatedCosts	4031000	USD
CY2019	us-gaap	Business Combination Acquisition Related Costs BusinessCombinationAcquisitionRelatedCosts	3370000	USD
CY2018	us-gaap	Business Combination Acquisition Related Costs BusinessCombinationAcquisitionRelatedCosts	5111000	USD
CY2020	us-gaap	Restructuring Costs And Asset Impairment Charges RestructuringCostsAndAssetImpairmentCharges	22652000	USD
CY2019	us-gaap	Restructuring Costs And Asset Impairment Charges RestructuringCostsAndAssetImpairmentCharges	24538000	USD
CY2018	us-gaap	Restructuring Costs And Asset Impairment Charges RestructuringCostsAndAssetImpairmentCharges	18139000	USD
CY2020	cien	Interest And Other Income Loss Net InterestAndOtherIncomeLossNet	964000	USD
CY2019	cien	Interest And Other Income Loss Net InterestAndOtherIncomeLossNet	3876000	USD
CY2018	cien	Interest And Other Income Loss Net InterestAndOtherIncomeLossNet	-12029000	USD
CY2020	us-gaap	Interest Expense InterestExpense	31321000	USD
CY2019	us-gaap	Interest Expense InterestExpense	37452000	USD
CY2018	us-gaap	Interest Expense InterestExpense	55249000	USD
CY2020	cien	Gain Losson Extinguishmentand Restructuringof Debt GainLossonExtinguishmentandRestructuringofDebt	-646000	USD
CY2019	cien	Gain Losson Extinguishmentand Restructuringof Debt GainLossonExtinguishmentandRestructuringofDebt	0	USD
CY2018	cien	Gain Losson Extinguishmentand Restructuringof Debt GainLossonExtinguishmentandRestructuringofDebt	-13887000	USD
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	94670000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	59756000	USD
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	493471000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	361291000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	253434000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	-344690000	USD
CY2020Q4	cien	Number Of Geographic Regions NumberOfGeographicRegions	3	region
CY2020	us-gaap	Revenues Revenues	3532157000	USD
CY2019	us-gaap	Revenues Revenues	3572131000	USD
CY2018	us-gaap	Revenues Revenues	3094286000	USD
CY2020Q4	cien	Property Plant And Equipment Finance Lease Right Of Use Asset After Accumulated Depreciation And Amortization And Operating Lease Right Of Use Asset PropertyPlantAndEquipmentFinanceLeaseRightOfUseAssetAfterAccumulatedDepreciationAndAmortizationAndOperatingLeaseRightOfUseAsset	329403000	USD
CY2019Q4	cien	Property Plant And Equipment Finance Lease Right Of Use Asset After Accumulated Depreciation And Amortization And Operating Lease Right Of Use Asset PropertyPlantAndEquipmentFinanceLeaseRightOfUseAssetAfterAccumulatedDepreciationAndAmortizationAndOperatingLeaseRightOfUseAsset	286884000	USD
CY2018Q4	cien	Government Grants Maximum Amount GovernmentGrantsMaximumAmount	57600000	CAD
CY2018Q4	cien	Government Grants Maximum Amount GovernmentGrantsMaximumAmount	43200000	USD
CY2018	cien	Government Grants Numberof Counterparties GovernmentGrantsNumberofCounterparties	3	government_entity
CY2020Q4	us-gaap	Grants Receivable GrantsReceivable	5100000	CAD
CY2020Q4	us-gaap	Grants Receivable GrantsReceivable	3900000	USD

Files In Submission

Name	View Source	Status
0000936395-20-000042-index-headers.html	Edgar Link	pending
0000936395-20-000042-index.html	Edgar Link	pending
0000936395-20-000042.txt	Edgar Link	pending
0000936395-20-000042-xbrl.zip	Edgar Link	pending
cien-20201031.htm	Edgar Link	pending
cien-20201031.xsd	Edgar Link	pending
cien-20201031_cal.xml	Edgar Link	unprocessable
cien-20201031_def.xml	Edgar Link	unprocessable
cien-20201031_g1.jpg	Edgar Link	pending
cien-20201031_htm.xml	Edgar Link	completed
cien-20201031_lab.xml	Edgar Link	unprocessable
cien-20201031_pre.xml	Edgar Link	unprocessable
ex103-2017rsuagree201218.htm	Edgar Link	pending
ex105-2017psuagree201218.htm	Edgar Link	pending
ex106-2017msuagree201218.htm	Edgar Link	pending
ex21120201031-subsidiaries.htm	Edgar Link	pending
ex2312020103110kpwcconsent.htm	Edgar Link	pending
ex3112020103110kceocert302.htm	Edgar Link	pending
ex3122020103110kcfocert302.htm	Edgar Link	pending
ex3212020103110kceocert906.htm	Edgar Link	pending
ex3222020103110kcfocert906.htm	Edgar Link	pending
ex42-descriptionofsecuriti.htm	Edgar Link	pending
FilingSummary.xml	Edgar Link	unprocessable
Financial_Report.xlsx	Edgar Link	pending
MetaLinks.json	Edgar Link	pending
R1.htm	Edgar Link	pending
R10.htm	Edgar Link	pending
R100.htm	Edgar Link	pending
R101.htm	Edgar Link	pending
R102.htm	Edgar Link	pending
R103.htm	Edgar Link	pending
R104.htm	Edgar Link	pending
R105.htm	Edgar Link	pending
R106.htm	Edgar Link	pending
R107.htm	Edgar Link	pending
R108.htm	Edgar Link	pending
R109.htm	Edgar Link	pending
R11.htm	Edgar Link	pending
R110.htm	Edgar Link	pending
R111.htm	Edgar Link	pending
R112.htm	Edgar Link	pending
R113.htm	Edgar Link	pending
R114.htm	Edgar Link	pending
R115.htm	Edgar Link	pending
R116.htm	Edgar Link	pending
R117.htm	Edgar Link	pending
R118.htm	Edgar Link	pending
R119.htm	Edgar Link	pending
R12.htm	Edgar Link	pending
R120.htm	Edgar Link	pending
R13.htm	Edgar Link	pending
R14.htm	Edgar Link	pending
R15.htm	Edgar Link	pending
R16.htm	Edgar Link	pending
R17.htm	Edgar Link	pending
R18.htm	Edgar Link	pending
R19.htm	Edgar Link	pending
R2.htm	Edgar Link	pending
R20.htm	Edgar Link	pending
R21.htm	Edgar Link	pending
R22.htm	Edgar Link	pending
R23.htm	Edgar Link	pending
R24.htm	Edgar Link	pending
R25.htm	Edgar Link	pending
R26.htm	Edgar Link	pending
R27.htm	Edgar Link	pending
R28.htm	Edgar Link	pending
R29.htm	Edgar Link	pending
R3.htm	Edgar Link	pending
R30.htm	Edgar Link	pending
R31.htm	Edgar Link	pending
R32.htm	Edgar Link	pending
R33.htm	Edgar Link	pending
R34.htm	Edgar Link	pending
R35.htm	Edgar Link	pending
R36.htm	Edgar Link	pending
R37.htm	Edgar Link	pending
R38.htm	Edgar Link	pending
R39.htm	Edgar Link	pending
R4.htm	Edgar Link	pending
R40.htm	Edgar Link	pending
R41.htm	Edgar Link	pending
R42.htm	Edgar Link	pending
R43.htm	Edgar Link	pending
R44.htm	Edgar Link	pending
R45.htm	Edgar Link	pending
R46.htm	Edgar Link	pending
R47.htm	Edgar Link	pending
R48.htm	Edgar Link	pending
R49.htm	Edgar Link	pending
R5.htm	Edgar Link	pending
R50.htm	Edgar Link	pending
R51.htm	Edgar Link	pending
R52.htm	Edgar Link	pending
R53.htm	Edgar Link	pending
R54.htm	Edgar Link	pending
R55.htm	Edgar Link	pending
R56.htm	Edgar Link	pending
R57.htm	Edgar Link	pending
R58.htm	Edgar Link	pending
R59.htm	Edgar Link	pending
R6.htm	Edgar Link	pending
R60.htm	Edgar Link	pending
R61.htm	Edgar Link	pending
R62.htm	Edgar Link	pending
R63.htm	Edgar Link	pending
R64.htm	Edgar Link	pending
R65.htm	Edgar Link	pending
R66.htm	Edgar Link	pending
R67.htm	Edgar Link	pending
R68.htm	Edgar Link	pending
R69.htm	Edgar Link	pending
R7.htm	Edgar Link	pending
R70.htm	Edgar Link	pending
R71.htm	Edgar Link	pending
R72.htm	Edgar Link	pending
R73.htm	Edgar Link	pending
R74.htm	Edgar Link	pending
R75.htm	Edgar Link	pending
R76.htm	Edgar Link	pending
R77.htm	Edgar Link	pending
R78.htm	Edgar Link	pending
R79.htm	Edgar Link	pending
R8.htm	Edgar Link	pending
R80.htm	Edgar Link	pending
R81.htm	Edgar Link	pending
R82.htm	Edgar Link	pending
R83.htm	Edgar Link	pending
R84.htm	Edgar Link	pending
R85.htm	Edgar Link	pending
R86.htm	Edgar Link	pending
R87.htm	Edgar Link	pending
R88.htm	Edgar Link	pending
R89.htm	Edgar Link	pending
R9.htm	Edgar Link	pending
R90.htm	Edgar Link	pending
R91.htm	Edgar Link	pending
R92.htm	Edgar Link	pending
R93.htm	Edgar Link	pending
R94.htm	Edgar Link	pending
R95.htm	Edgar Link	pending
R96.htm	Edgar Link	pending
R97.htm	Edgar Link	pending
R98.htm	Edgar Link	pending
R99.htm	Edgar Link	pending
report.css	Edgar Link	pending
Show.js	Edgar Link	pending

Create your account

Find Stocks Worth Researching

Deeply Understand Businesses

Value Businesses Intelligently

$CIEN
CIENA CORP Stock $cien

2020 Q4 Form 10-K Financial Statement

#000093639520000042 Filed on December 18, 2020

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$CIEN CIENA CORP Stock $cien

2020 Q4 Form 10-K Financial Statement

#000093639520000042 Filed on December 18, 2020

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$CIEN
CIENA CORP Stock $cien