CENX


Line plots across dimensions of each concept
Line plots across concepts
Tables

Table of contents



us-gaap:CommonStockValue
us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems
us-gaap:ConsolidationItems

us-gaap:WeightedAverageNumberOfDilutedSharesOutstanding

us-gaap:WeightedAverageNumberOfSharesOutstandingBasic

us-gaap:WeightedAverageNumberOfShareOutstandingBasicAndDiluted

us-gaap:AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount
us-gaap:AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecurities

us-gaap:EarningsPerShareBasic

us-gaap:EarningsPerShareDiluted

us-gaap:EarningsPerShareBasicAndDiluted

us-gaap:ComprehensiveIncomeNetOfTax

us-gaap:ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest
us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems
us-gaap:ConsolidationItems

us-gaap:CostOfGoodsAndServicesSold
us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems
us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:StatementEquityComponents

us-gaap:GainsLossesOnExtinguishmentOfDebt
us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems
us-gaap:DebtInstrument, us-gaap:LongtermDebtType
us-gaap:LongtermDebtType

us-gaap:GrossProfit
us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

us-gaap:IncomeTaxExpenseBenefit
us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems
us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:StatementEquityComponents

us-gaap:IncomeTaxesPaid

us-gaap:InterestExpenseDebt
us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

us-gaap:InterestPaidNet

us-gaap:NetIncomeLoss
us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems
us-gaap:ConsolidationItems
us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:StatementEquityComponents
us-gaap:StatementEquityComponents

us-gaap:NetIncomeLossAvailableToCommonStockholdersBasic

us-gaap:NetIncomeLossAvailableToCommonStockholdersDiluted

us-gaap:OperatingIncomeLoss
us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

us-gaap:OtherComprehensiveIncomeLossNetOfTax
us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems
us-gaap:ConsolidationItems
us-gaap:StatementEquityComponents

us-gaap:OtherNonoperatingIncomeExpense
us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax
us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems
us-gaap:StatementGeographical

us-gaap:Revenues

us-gaap:SellingGeneralAndAdministrativeExpense
us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems
us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:StatementEquityComponents

us-gaap:Assets
us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems
us-gaap:ConsolidationItems

us-gaap:LiabilitiesAndStockholdersEquity
us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems
us-gaap:ConsolidationItems

us-gaap:StockholdersEquity
us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems
us-gaap:ConsolidationItems
us-gaap:StatementEquityComponents

us-gaap:AssetsCurrent
us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

us-gaap:CashAndCashEquivalentsAtCarryingValue
us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents
us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

us-gaap:AccountsReceivableNetCurrent
us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

us-gaap:InventoryNet
us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

us-gaap:PrepaidExpenseAndOtherAssetsCurrent
us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

us-gaap:MachineryAndEquipmentGross
us-gaap:StatementGeographical
us-gaap:NoncurrentAssets

us-gaap:PropertyPlantAndEquipmentGross

us-gaap:ConstructionInProgressGross

us-gaap:AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment

us-gaap:PropertyPlantAndEquipmentNet
us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems
us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems
us-gaap:InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures
us-gaap:ConsolidationItems

us-gaap:OperatingLeaseRightOfUseAsset

us-gaap:OtherAssetsNoncurrent
us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

us-gaap:AccruedLiabilitiesCurrent

us-gaap:LiabilitiesCurrent
us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

us-gaap:OperatingLeaseLiabilityCurrent
us-gaap:CounterpartyName
us-gaap:OtherLiabilitiesCurrent

us-gaap:LiabilitiesNoncurrent
us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems
us-gaap:ConsolidationItems
us-gaap:DebtInstrument, us-gaap:LongtermDebtType
us-gaap:SecuredLongTermDebt

us-gaap:DeferredIncomeTaxLiabilitiesNet
us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems
us-gaap:RetirementPlanType
us-gaap:PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent

us-gaap:OtherLiabilitiesNoncurrent
us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

us-gaap:OperatingLeaseLiabilityNoncurrent
us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearTwo

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearThree

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFour

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFive

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive

us-gaap:OperatingLeaseLiability

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDue

us-gaap:LesseeOperatingLeaseLiabilityUndiscountedExcessAmount

us-gaap:StockholdersEquity
us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems
us-gaap:ConsolidationItems
us-gaap:StatementEquityComponents

us-gaap:CommonStockValue
us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems
us-gaap:ConsolidationItems

us-gaap:AdditionalPaidInCapital

us-gaap:RetainedEarningsAccumulatedDeficit

us-gaap:AccumulatedOtherComprehensiveIncomeLossNetOfTax

us-gaap:TreasuryStockValue

us-gaap:AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue
us-gaap:StatementEquityComponents

us-gaap:NetCashProvidedByUsedInOperatingActivities
us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

us-gaap:NetCashProvidedByUsedInInvestingActivities
us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems
us-gaap:ConsolidationItems

us-gaap:NetCashProvidedByUsedInFinancingActivities
us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems
us-gaap:ConsolidationItems

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect
us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

us-gaap:DepreciationDepletionAndAmortization

us-gaap:IncreaseDecreaseInAccountsReceivable

us-gaap:IncreaseDecreaseInInventories

us-gaap:IncreaseDecreaseInOtherOperatingCapitalNet

us-gaap:NetCashProvidedByUsedInOperatingActivities
us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

us-gaap:NetIncomeLoss
us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems
us-gaap:ConsolidationItems
us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:StatementEquityComponents
us-gaap:StatementEquityComponents

us-gaap:NetCashProvidedByUsedInInvestingActivities
us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems
us-gaap:ConsolidationItems

us-gaap:PaymentsToAcquirePropertyPlantAndEquipment
us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

us-gaap:NetCashProvidedByUsedInFinancingActivities
us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems
us-gaap:ConsolidationItems
us-gaap:DebtInstrument, us-gaap:LongtermDebtType
us-gaap:DebtInstrumentInterestRateStatedPercentage

us-gaap:DeferredTaxLiabilities

us-gaap:DeferredTaxAssetsNet

us-gaap:UnrecognizedTaxBenefits

us-gaap:DeferredTaxAssetsValuationAllowance
us-gaap:ValuationAllowanceByDeferredTaxAsset

cenx:AdjustmentsToAdditionalPaidInCapitalOptionIndexedToIssuersEquityCappedCallPremium
us-gaap:StatementEquityComponents

cenx:CapitalExpendituresNonCashInvestingActivity
us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName
cenx:DiscreteTaxBenefitExpense

cenx:EquityInEarningsOfJointVenture
us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems
us-gaap:ConsolidationItems
us-gaap:DerivativeInstrumentRisk
cenx:FairValueNetDerivativeAssetLiabilityMeasuredonRecurringBasisUnobservableInputsReconciliationUnrealizedGainsLosses

cenx:GainLossOnExtinguishmentOfDebtNet

cenx:IncomeLossAfterIncomeTaxesBeforeIncomeLossFromEquityMethodInvestments
us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

cenx:IncomeLossBeforeIncomeTaxesAndEquityMethodInvestmentsInNoncontrollingInterest
us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems
us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems
cenx:InterestExpenseIntercompany
us-gaap:BalanceSheetLocation, us-gaap:LossContingenciesByNatureOfContingency
cenx:LitigationSettlementAmountAwardedtoOtherPartyAnnualPayments
us-gaap:LossContingenciesByNatureOfContingency

cenx:NetIncomeLossAvailabletoCommonStockholdersBasicandDiluted
us-gaap:DebtInstrument, us-gaap:OptionIndexedToIssuersEquityEquity
cenx:OptionIndexedToIssuersEquityCapPrice
us-gaap:DebtInstrument, us-gaap:OptionIndexedToIssuersEquityEquity
cenx:OptionIndexedToIssuersEquityIssuanceCost

cenx:PaymentOfDebtRetirementCostsNet
us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems
us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems
cenx:PaymentsforProceedsfromIntercompanyTransactionsFinancingActivities
us-gaap:ConsolidationItems
us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems
cenx:PaymentsforProceedsfromIntercompanyTransactionsInvestingActivities
us-gaap:ConsolidationItems
us-gaap:CounterpartyName
cenx:PensionContributionsAboveRequiredMinimumRemaining

cenx:RepaymentsofTermLoan
us-gaap:DebtInstrument, us-gaap:LongtermDebtType, us-gaap:SubsequentEventType
cenx:WriteOffOfDeferredFinancingCost
us-gaap:LongtermDebtType
us-gaap:ConcentrationRiskByBenchmark, us-gaap:ConcentrationRiskByType, us-gaap:RelatedPartyTransactionsByRelatedParty
us-gaap:ConcentrationRiskPercentage1
us-gaap:MajorCustomers, us-gaap:ConcentrationRiskByBenchmark, us-gaap:ConcentrationRiskByType
us-gaap:DebtInstrument, us-gaap:LongtermDebtType
us-gaap:DebtInstrumentRedemptionPricePercentage
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanAmortizationOfGainsLosses
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanAmortizationOfPriorServiceCostCredit
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanExpectedReturnOnPlanAssets
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanInterestCost
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanNetPeriodicBenefitCost
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanServiceCost

us-gaap:DerivativeGainLossOnDerivativeNet
us-gaap:DerivativeInstrumentRisk
us-gaap:DerivativeInstrumentRisk, us-gaap:RelatedPartyTransactionsByRelatedParty
us-gaap:DebtInstrument, us-gaap:OptionIndexedToIssuersEquityEquity
us-gaap:DerivativeLossOnDerivative
us-gaap:DerivativeInstrumentRisk
us-gaap:DerivativeNonmonetaryNotionalAmountMass
us-gaap:DerivativeInstrumentRisk
us-gaap:FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisUnobservableInputsReconciliationGainLossIncludedInEarnings
us-gaap:DerivativeInstrumentRisk
us-gaap:FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisUnobservableInputsReconciliationSettlements
us-gaap:DerivativeInstrumentRisk
us-gaap:FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisUnobservableInputsReconciliationTransfersIntoLevel3
us-gaap:DerivativeInstrumentRisk
us-gaap:FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisUnobservableInputsReconciliationTransfersOutOfLevel3

us-gaap:ForeignCurrencyCashFlowHedgeGainLossReclassifiedToEarningsNet

us-gaap:GainLossOnDerivativeInstrumentsNetPretax
us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

us-gaap:IncomeLossAttributableToParent

us-gaap:IncreaseDecreaseInAccountsPayableTrade

us-gaap:IncreaseDecreaseInAccruedLiabilities

us-gaap:IncreaseDecreaseInDueFromRelatedPartiesCurrent

us-gaap:IncreaseDecreaseInDueToRelatedPartiesCurrent

us-gaap:IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets

us-gaap:InterestExpenseRelatedParty
us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

us-gaap:InterestIncomeOther
us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

us-gaap:InventoryWriteDown
us-gaap:StatementGeographical, us-gaap:LossContingenciesByNatureOfContingency
us-gaap:LitigationSettlementAmountAwardedToOtherParty
us-gaap:DebtInstrument, us-gaap:OptionIndexedToIssuersEquityEquity
us-gaap:OptionIndexedToIssuersEquityStrikePrice1

us-gaap:OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditBeforeTax

us-gaap:OtherComprehensiveIncomeLossBeforeTax
us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems
us-gaap:ConsolidationItems

us-gaap:OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax

us-gaap:OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent
us-gaap:StatementEquityComponents

us-gaap:OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossBeforeTax

us-gaap:OtherComprehensiveIncomeLossTax
us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

us-gaap:OtherOperatingActivitiesCashFlowStatement

us-gaap:OtherOperatingIncome
us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

us-gaap:OtherOperatingIncomeExpenseNet
us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems
us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:StatementEquityComponents

us-gaap:PaymentsOfDebtIssuanceCosts
us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems
us-gaap:DebtInstrument, us-gaap:LongtermDebtType
us-gaap:ProceedsFromConvertibleDebt

us-gaap:ProceedsFromIssuanceOfDebt
us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems
us-gaap:DebtInstrument
us-gaap:DebtInstrument, us-gaap:LongtermDebtType
us-gaap:ProceedsFromIssuanceOfSeniorLongTermDebt

us-gaap:ProceedsFromLinesOfCredit
us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

us-gaap:ProceedsFromSaleOfPropertyPlantAndEquipment
us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

us-gaap:ReclassificationFromAociCurrentPeriodNetOfTaxAttributableToParent
us-gaap:StatementEquityComponents
us-gaap:LongtermDebtType
us-gaap:RedemptionPremium
us-gaap:MajorCustomers
us-gaap:RelatedPartyCosts
us-gaap:RelatedPartyTransactionsByRelatedParty

us-gaap:RepaymentsOfLinesOfCredit
us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

us-gaap:RevenueFromRelatedParties
us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems
us-gaap:MajorCustomers
us-gaap:MajorCustomers, us-gaap:ProductOrService
us-gaap:ProductOrService, us-gaap:RelatedPartyTransactionsByRelatedParty
us-gaap:RelatedPartyTransactionsByRelatedParty

us-gaap:UnrealizedGainLossOnDerivatives

cenx:AccruedLiabilitiesCurrentandOther
us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

cenx:AccumulatedOtherComprehensiveIncomeTaxEffect
us-gaap:StatementEquityComponents
us-gaap:BalanceSheetLocation, us-gaap:DebtInstrument
cenx:ContingentObligationAccruedInterest
us-gaap:BalanceSheetLocation, us-gaap:DebtInstrument
cenx:ContingentObligationDerivativeAsset
us-gaap:BalanceSheetLocation, us-gaap:DebtInstrument
cenx:ContingentObligationPrincipal

cenx:DebtDomestic
us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

cenx:DebtForeign

cenx:DebtForeignNoncurrent
us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems
us-gaap:DebtInstrument, us-gaap:LongtermDebtType
cenx:DebtInstrumentInterestRateStatedPercentageAdditionalNotesOrCash
us-gaap:DebtInstrument, us-gaap:LongtermDebtType, us-gaap:SubsequentEventType
us-gaap:DebtInstrument, us-gaap:LongtermDebtType
cenx:DebtInstrumentInterestRateStatedPercentageCash
us-gaap:DebtInstrument, us-gaap:LongtermDebtType, us-gaap:SubsequentEventType
us-gaap:DebtInstrument
cenx:DebtInstrumentPrincipalPayment
us-gaap:DebtInstrument, us-gaap:ShortTermDebtType
us-gaap:DebtInstrument
cenx:DebtInstrumentTenderPremium
us-gaap:DebtInstrument, us-gaap:LongtermDebtType, us-gaap:SubsequentEventType

cenx:DebtOfferToPurchasePercentageOfOutstandingAmount
us-gaap:DebtInstrument, us-gaap:LongtermDebtType

cenx:DeferredTaxAssetsForeignBasisDifferences
us-gaap:Ownership
cenx:EconomicOwnershipPercentageByRelatedParty

cenx:IndustrialRevenueBonds
us-gaap:DebtInstrument, us-gaap:ShortTermDebtType
us-gaap:CreditFacility
cenx:LineOfCreditFacilityAdditionalBorrowingsUnderLetterOfCreditSubFacility
us-gaap:CreditFacility
cenx:LineofCreditFacilityRemainingBorrowingCapacityNetofLettersofCredit
us-gaap:CreditFacility, us-gaap:DebtInstrument
us-gaap:CreditFacility, us-gaap:LongtermDebtType
us-gaap:DerivativeInstrumentRisk
cenx:OtherPrimaryAluminumDeliveryCommitmentsAndContractsOpenPositionVolume

cenx:OtherShareholdersEquity
us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems
us-gaap:ConsolidationItems

cenx:PercentageOfDomesticWorkForceInUnion

cenx:PercentageOfForeignWorkForceCoveredUnderNewLaborAgreement

cenx:PercentageofWorkForceinUnion
dei:LegalEntity, us-gaap:CounterpartyName
cenx:PowerSupplyAgreementTotalProductionPercentage
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency
cenx:PrimaryAluminumSalesContractsPremiumCollarFairValueDisclosure
us-gaap:FairValueByMeasurementFrequency

cenx:SegmentReportingCorporateUnallocatedAssets

cenx:SegmentReportingPrimaryAssets

cenx:TrustAssetsFairValueDisclosure
us-gaap:FairValueByFairValueHierarchyLevel
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency
us-gaap:FairValueByMeasurementFrequency
us-gaap:DerivativeInstrumentRisk
cenx:UnderlyingDerivativeEnergyAvailable
us-gaap:CounterpartyName
cenx:UnderlyingDerivativePowerAvailable
us-gaap:CounterpartyName
cenx:UnderlyingDerivativePowerAvailableExtension
us-gaap:CounterpartyName
cenx:UnderlyingDerivativePowerAvailableRequested

us-gaap:AccountsPayableTradeCurrent
us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

us-gaap:AccumulatedOtherComprehensiveIncomeLossBeforeTax1
us-gaap:StatementEquityComponents

us-gaap:AllowanceForDoubtfulAccountsReceivable

us-gaap:AssetRetirementObligation

us-gaap:AssetsFairValueDisclosure
us-gaap:FairValueByFairValueHierarchyLevel
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency
us-gaap:FairValueByMeasurementFrequency

us-gaap:BuildingsAndImprovementsGross

us-gaap:CashAndCashEquivalentsFairValueDisclosure
us-gaap:FairValueByFairValueHierarchyLevel
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency
us-gaap:FairValueByMeasurementFrequency

us-gaap:ConvertibleLongTermNotesPayable
us-gaap:DebtInstrument, us-gaap:LongtermDebtType
us-gaap:DebtInstrument, us-gaap:LongtermDebtType
us-gaap:DebtInstrumentFaceAmount
us-gaap:DebtInstrument, us-gaap:LongtermDebtType, us-gaap:SubsequentEventType
us-gaap:DebtInstrument, us-gaap:SubsequentEventType
us-gaap:DebtInstrument, us-gaap:FairValueByFairValueHierarchyLevel
us-gaap:DebtInstrumentFairValue
us-gaap:DebtInstrument, us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:LongtermDebtType
us-gaap:DebtInstrument, us-gaap:LongtermDebtType
us-gaap:DebtInstrumentFeeAmount
us-gaap:DebtInstrument
us-gaap:DebtInstrumentInterestRateEffectivePercentage
us-gaap:Range, us-gaap:DebtInstrument, us-gaap:ShortTermDebtType
us-gaap:DebtInstrument, us-gaap:LongtermDebtType
us-gaap:DebtInstrumentRepurchasedFaceAmount
us-gaap:DebtInstrument, us-gaap:LongtermDebtType, us-gaap:SubsequentEventType
us-gaap:DebtInstrument, us-gaap:LongtermDebtType
us-gaap:DebtInstrumentUnamortizedDiscount
us-gaap:DebtInstrument, us-gaap:LongtermDebtType, us-gaap:SubsequentEventType
us-gaap:LongtermDebtType

us-gaap:DebtLongtermAndShorttermCombinedAmount
us-gaap:PlanName
us-gaap:DeferredCompensationLiabilityCurrentAndNoncurrent

us-gaap:DeferredIncomeTaxLiabilities

us-gaap:DeferredTaxAssetsGross

us-gaap:DeferredTaxAssetsOperatingLossCarryforwards

us-gaap:DeferredTaxAssetsOther

us-gaap:DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsPostretirementBenefits

us-gaap:DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsShareBasedCompensationCost

us-gaap:DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAccruedLiabilities

us-gaap:DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsLegalSettlements

us-gaap:DeferredTaxLiabilitiesPropertyPlantAndEquipment

us-gaap:DefinedBenefitPensionPlanLiabilitiesNoncurrent
us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeBeforeTax
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetGainsLossesBeforeTax
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetPriorServiceCostCreditBeforeTax
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanAmountsRecognizedInBalanceSheet
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationRateOfCompensationIncrease
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanBenefitObligation
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsFiveFiscalYearsThereafter
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsNextTwelveMonths
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFive
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFour
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsYearThree
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsYearTwo
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanExpectedFutureEmployerContributionsNextFiscalYear

us-gaap:DefinedBenefitPlanFairValueOfPlanAssets
us-gaap:DefinedBenefitPlanByPlanAssetCategories
us-gaap:DefinedBenefitPlanByPlanAssetCategories, us-gaap:FairValueByFairValueHierarchyLevel
us-gaap:FairValueByFairValueHierarchyLevel
us-gaap:RetirementPlanType
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanFundedStatusOfPlan
cenx:PlanParticipantType
us-gaap:DefinedBenefitPlanHealthCareCostTrendRateAssumedNextFiscalYear
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateAccumulatedBenefitObligation
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateFairValueOfPlanAssets
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateProjectedBenefitObligation

us-gaap:DefinedBenefitPlanUltimateHealthCareCostTrendRate1
us-gaap:DefinedBenefitPlanByPlanAssetCategories
us-gaap:DefinedBenefitPlanWeightedAverageAssetAllocations
us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByFairValueHierarchyLevel
us-gaap:DerivativeAssetMeasurementInput

us-gaap:DerivativeAssets
us-gaap:DerivativeInstrumentRisk
us-gaap:FairValueByFairValueHierarchyLevel
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency
us-gaap:FairValueByMeasurementFrequency

us-gaap:DerivativeAssetsCurrent
us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems
us-gaap:DerivativeInstrumentRisk, us-gaap:HedgingDesignation
us-gaap:DerivativeFairValueOfDerivativeAsset
us-gaap:HedgingDesignation
us-gaap:DerivativeInstrumentRisk, us-gaap:HedgingDesignation
us-gaap:DerivativeFairValueOfDerivativeLiability
us-gaap:HedgingDesignation

us-gaap:DerivativeLiabilities
us-gaap:FairValueByFairValueHierarchyLevel
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency
us-gaap:FairValueByMeasurementFrequency

us-gaap:DerivativeLiabilitiesCurrent

us-gaap:DerivativeLiabilitiesNoncurrent
us-gaap:DerivativeInstrumentRisk, us-gaap:RelatedPartyTransactionsByRelatedParty
us-gaap:DueFromAffiliateCurrent
us-gaap:DerivativeInstrumentRisk, us-gaap:RelatedPartyTransactionsByRelatedParty
us-gaap:DueFromAffiliateNoncurrent

us-gaap:DueFromRelatedPartiesCurrent
us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems
us-gaap:DerivativeInstrumentRisk, us-gaap:RelatedPartyTransactionsByRelatedParty

us-gaap:DueFromRelatedPartiesNoncurrent
us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems
us-gaap:ConsolidationItems
us-gaap:DerivativeInstrumentRisk, us-gaap:RelatedPartyTransactionsByRelatedParty

us-gaap:DueToAffiliateCurrent
us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems
us-gaap:DerivativeInstrumentRisk, us-gaap:RelatedPartyTransactionsByRelatedParty

us-gaap:DueToAffiliateNoncurrent
us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems
us-gaap:ConsolidationItems
us-gaap:DerivativeInstrumentRisk, us-gaap:RelatedPartyTransactionsByRelatedParty

us-gaap:EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized
us-gaap:DerivativeInstrumentRisk
us-gaap:FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisWithUnobservableInputs

us-gaap:InterestPayableCurrent
us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems
us-gaap:DebtInstrument
us-gaap:InterestPayableCurrentAndNoncurrent
us-gaap:DebtInstrument, us-gaap:ShortTermDebtType

us-gaap:InventoryFinishedGoodsNetOfReserves

us-gaap:InventoryRawMaterialsNetOfReserves

us-gaap:InventorySuppliesNetOfReserves

us-gaap:InventoryWorkInProcessNetOfReserves
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency
us-gaap:InvestmentsFairValueDisclosure
us-gaap:FairValueByMeasurementFrequency

us-gaap:LandAndLandImprovements

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths
us-gaap:CreditFacility
us-gaap:LettersOfCreditOutstandingAmount
us-gaap:CreditFacility, us-gaap:DebtInstrument

us-gaap:LiabilitiesFairValueDisclosure
us-gaap:FairValueByFairValueHierarchyLevel
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency
us-gaap:FairValueByMeasurementFrequency
us-gaap:CreditFacility
us-gaap:LineOfCredit
us-gaap:CreditFacility, us-gaap:DebtInstrument
us-gaap:CreditFacility, us-gaap:LongtermDebtType
us-gaap:CreditFacility, us-gaap:ShortTermDebtType
us-gaap:CreditFacility
us-gaap:LineOfCreditFacilityRemainingBorrowingCapacity
us-gaap:CreditFacility, us-gaap:DebtInstrument
us-gaap:CreditFacility, us-gaap:LongtermDebtType

us-gaap:NotesPayableRelatedPartiesClassifiedCurrent
us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems
us-gaap:RelatedPartyTransactionsByRelatedParty
us-gaap:RelatedPartyTransactionsByRelatedParty, us-gaap:ShortTermDebtType

us-gaap:NotesPayableRelatedPartiesNoncurrent
us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems
us-gaap:RelatedPartyTransactionsByRelatedParty
us-gaap:IncomeTaxAuthority
us-gaap:OperatingLossCarryforwards
us-gaap:CounterpartyName
us-gaap:OtherLiabilities

us-gaap:OtherPostretirementDefinedBenefitPlanLiabilitiesNoncurrent
us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

us-gaap:PensionAndOtherPostretirementDefinedBenefitPlansCurrentLiabilities
us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems
us-gaap:RetirementPlanType

us-gaap:PreferredStockValue

us-gaap:RestrictedCashAndCashEquivalents
us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems
us-gaap:CreditFacility, us-gaap:DebtInstrument
us-gaap:SecuredDebt
us-gaap:CreditFacility, us-gaap:DebtInstrument, us-gaap:LongtermDebtType
us-gaap:DebtInstrument
us-gaap:CreditFacility, us-gaap:DebtInstrument
us-gaap:SecuredDebtCurrent
us-gaap:CreditFacility, us-gaap:DebtInstrument, us-gaap:ShortTermDebtType

us-gaap:SeniorLongTermNotes
us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

us-gaap:SignificantChangeInUnrecognizedTaxBenefitsIsReasonablyPossibleAmountOfUnrecordedBenefit

us-gaap:StockRepurchaseProgramRemainingAuthorizedRepurchaseAmount1

us-gaap:UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate

us-gaap:ValuationAllowancesAndReservesBalance

Plots across concepts


IncomeStatement
Net Income Loss
Expenses
Income Tax Expense Benefit
Balance Sheet
Cash And Cash Equivalents At Carrying Value
Assets
Cash And Cash Equivalents At Carrying Value
Current Assets
Cash And Cash Equivalents At Carrying Value
NonCurrent Assets
Operating Lease Right Of Use Asset
PropertyPlantAndEquipmentNet
Property Plant And Equipment Net
Liabilities
Derivative Liabilities
Current Liabilities
Operating Lease Liability Current
Stockholders Equity
Retained Earnings Accumulated Deficit
CashFlow
Net Cash Provided By Used In Operating Activities
NetCashProvidedByUsedInOperatingActivities
Net Cash Provided By Used In Operating Activities
NetCashProvidedByUsedInInvestingActivities
Net Cash Provided By Used In Investing Activities
Shares
Weighted Average Number Of Diluted Shares Outstanding
OperatingLeaseLiability
Operating Lease Liability Current
LesseeOperatingLeaseLiabilityPaymentsDue
Lessee Operating Lease Liability Payments Due Year Four
InventoryNet
Inventory Finished Goods Net Of Reserves

Tables

  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
us-gaap:CommonStockValue ███████████▁▁▁▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▃▃▃▃▃▃▃▃▃▃▃▃▃1.01.01.01.01.01.01.01.01.01.01.00.90.90.90.9470.9450.9450.9440.9440.9420.9420.9420.9420.9410.9410.9390.9390.9370.9360.9360.9350.9350.9340.9340.9330.9330.9330.9320.9320.9320.9320.9310.928NANANA
us-gaap:WeightedAverageNumberOfDilutedSharesOutstanding 90.1NANANA89.5NANANA88.8NANA87.688.487.6NA88.25588.05787.3NA87.07687.0687.04NA86.90786.87389.369NA89.53289.35288.717NA88.61188.59789.02NA88.46888.45288.727NA92.03293.56793.297NANANANA
us-gaap:WeightedAverageNumberOfSharesOutstandingBasic 90.1NANANA89.5NANANA88.888.1NA87.687.687.6NA87.31887.27287.3NA87.07687.0687.04NA86.90786.87388.814NA88.82788.78788.717NA88.6110.576510.415958NA0.406070.3957910.345524NA0.3233960.343148NANANANANA
us-gaap:WeightedAverageNumberOfShareOutstandingBasicAndDiluted NA90.1NA89.589.589.3NA88.988.888.1NA87.6NA87.6NANANA87.254NA87.076NA87.04NA86.907NANANANANANANANANANANANANANANANANANANANANANA
us-gaap:AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount █▁2.42.2NA1.70.60.4NA0.70.70.6NA1.30.61.4NA0.5350.4325061.2NA1.8221.800096NANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:EarningsPerShareBasic -0.39NA-0.4-0.65-0.3-0.03-0.05-0.23-0.23-0.39-0.74-0.230.20.00.380.220.08-0.17-1.93-0.67-0.11-0.19-0.5-0.65-0.390.760.640.520.21-0.23-0.11-0.11-0.390.09-0.08000000000000002-0.14-0.14NANA-0.070.240.25NA-0.180.050.06
us-gaap:EarningsPerShareDiluted -0.39NA-0.4-0.65-0.3-0.03-0.05-0.23-0.23-0.39-0.74-0.230.20.00.370.220.07-0.17-1.93-0.67-0.11-0.19-0.5-0.65-0.390.760.630.520.21-0.23-0.11-0.11-0.390.09-0.08000000000000002-0.14-0.14NANA-0.070.240.25NA-0.180.050.06
us-gaap:EarningsPerShareBasicAndDiluted NA-1.55-0.3999999999999999-0.65-0.3-0.03-0.050000000000000044-0.23-0.23-0.39-0.75-0.230.20.0NANANA-0.17-1.94-0.67NA-0.19-0.49000000000000005-0.65NA0.76NA0.520.21-0.23-0.11-0.11-0.390.09-0.08-0.14-0.14-0.05-0.35-0.070.240.250.65-0.180.050.06
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
 COGS Ratio us-gaap:ConsolidatedEntities,us-gaap:ConsolidationItems srt:GuarantorSubsidiaries,srt:ReportableLegalEntitiesNANA110.6116.4156.2147.9133.7132.9147.4152.5138.5110.893.6110.7143.4138.2NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 Gross Margin us-gaap:ConsolidatedEntities,us-gaap:ConsolidationItems srt:GuarantorSubsidiaries,srt:ReportableLegalEntitiesNANA110.6116.4156.2147.9133.7132.9147.4152.5138.5110.893.6110.7143.4138.2NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 Operating Margin us-gaap:ConsolidatedEntities,us-gaap:ConsolidationItems srt:GuarantorSubsidiaries,srt:ReportableLegalEntitiesNANA110.6116.4156.2147.9133.7132.9147.4152.5138.5110.893.6110.7143.4138.2NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
 TTM Greenblatt ROC _ _▆▅▅▅▅▆▆▅▅▅▄▅▆▆▇▇▆▆▁▄▆▅▅▄▅██▇▆▅▅▆▅▆▆▅▆▆▅▆▇▇█12.1-36.9-13.2-37.9-25.0-4.4-2.9-25.2-16.3-27.8-68.4-15.621.53.543.28332.47112.9285.176-159.644-55.053-4.941-13.558-28.486-55.526-35.12180.04566.85162.15126.012-14.234-8.631-4.242-23.870.1872.645-13.32-5.0118.412-27.1720.71536.16237.59179.625NANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
us-gaap:ComprehensiveIncomeNetOfTax -34.0NANANA-26.2NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest NA-138.7-47.69999999999999-57.1-26.2-1.3-16.6-20.0-19.7-34.3-75.1-20.222.00.156.02821.837.3-14.427-172.178-57.449-8.691-15.34-53.864-59.736-14.53573.85723.53350.25220.213-20.00537.173-9.024-23.4399.148-27.208-10.849-10.512-3.645-87.794-6.2677.08513.689NANANANA
 us-gaap:ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest us-gaap:ConsolidatedEntities,us-gaap:ConsolidationItems srt:GuarantorSubsidiaries,srt:ReportableLegalEntitiesNANA-24.8-26.6-12.9-2.6-6.0-4.64.40.9-81.8-9.223.29.625.519.2NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest us-gaap:ConsolidatedEntities,us-gaap:ConsolidationItems srt:NonGuarantorSubsidiaries,srt:ReportableLegalEntitiesNANA-14.1-7.1-0.6-25.7-17.3-14.2-20.3-20.6-21.5-3.73.7-3.611.514.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest us-gaap:ConsolidatedEntities,us-gaap:ConsolidationItems srt:ParentCompany,srt:ReportableLegalEntitiesNANA-47.69999999999999-57.1-26.2-1.4-16.6-20.0-19.7-34.3-75.1-20.222.00.156.121.8NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest us-gaap:ConsolidationItems srt:ConsolidationEliminationsNANA38.933.713.528.423.318.815.919.7103.312.9-26.9-6.0-37.0-33.2NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:CostOfGoodsAndServicesSold ▇▅▂▃▃▃▄▄▅▆█▆▄▄▂▁507.1464.7390.3420.0414.9416.4428.7451.7477.2502.8546.2493.6436.3440.0383.3359.2NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:GainsLossesOnExtinguishmentOfDebt -24.7NA0.0-1.2NANANANANANANANANANANANANANANANANANANANANANA0.00.00.0NA0.00.0-3.272NA0.00.00.0NA-0.7630.0NANA0.00.0NANA
 us-gaap:GainsLossesOnExtinguishmentOfDebt us-gaap:ConsolidatedEntities,us-gaap:ConsolidationItems srt:ParentCompany,srt:ReportableLegalEntitiesNANA0.0-1.2NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:GainsLossesOnExtinguishmentOfDebt us-gaap:DebtInstrument,us-gaap:LongtermDebtType cenx:SeniorSecuredNotesDueJune012021,us-gaap:LongTermDebtNANA0.01.2NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:GainsLossesOnExtinguishmentOfDebt us-gaap:LongtermDebtType us-gaap:SeniorNotesNANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:GrossProfit ▅▃▄▂▃▄▄▃▄▃▁▃▅▄▆▆▅▄▄▃▄▄▃▂▄██▇▅▄▄▄▃▅▄▄▄▅▃▄▆▆▆▄▅▅20.9-20.7-1.2-27.1-13.04.86.7-13.7-4.1-12.8-59.3-11.833.714.547.89241.40222.4616.8515.057-17.6125.582-3.052-18.701-42.4238.34294.09589.99675.71438.504-1.75815.28512.354-5.69817.58216.5433.255.95720.592-13.63211.32449.51442.31641.13515.76921.51633.976
us-gaap:IncomeTaxExpenseBenefit ▁▆▆▇▇▆▆▇▆▆▆▇▇▇▇▇▇▇▇▇▇▆▆▆▇██▇▇▇▆▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇-48.3-2.3-1.50.30.9-2.8-2.7-1.3-1.6-2.9-3.21.72.3-1.03.1183.3211.452-0.3086.061-0.848-0.319-2.07-2.929-2.1615.0659.30111.3046.4441.654-1.094-1.5831.3842.7912.5171.5261.1683.3952.8212.2135.3873.6363.1232.803-0.574.6194.281
 us-gaap:IncomeTaxExpenseBenefit us-gaap:ConsolidatedEntities,us-gaap:ConsolidationItems srt:NonGuarantorSubsidiaries,srt:ReportableLegalEntitiesNANA-1.30.31.4-2.3-1.7-0.6-1.7-1.9-1.32.22.6-1.13.43.3NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:IncomeTaxExpenseBenefit us-gaap:ConsolidatedEntities,us-gaap:ConsolidationItems srt:ParentCompany,srt:ReportableLegalEntitiesNANA-0.2-0.0-0.5-0.50.4-0.70.1-1.0-1.9-0.5-0.30.10.60.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:IncomeTaxExpenseBenefit us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome,us-gaap:StatementEquityComponents us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome,us-gaap:AccumulatedDefinedBenefitPlansAdjustment▂▂▆▂▂▂▆▂▂▂█▂▂▂█▂▂▅▃▃▃▃▂▂▂▂▂▁▁▁█▂▂▂-0.1-0.11.9-0.2-0.3-0.31.9-0.3-0.3-0.32.7-0.4-0.4-0.42.737-0.391-0.3011.0830.3350.390.3910.391-0.396-0.392-0.39-0.3910.0-0.548-0.559-0.7032.651-0.374-0.374-0.374NANANANANANANANANANANANA
 us-gaap:IncomeTaxExpenseBenefit us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome,us-gaap:StatementEquityComponents us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome,us-gaap:AccumulatedGainLossNetCashFlowHedgeParent██▁███▁███████0.00.0-0.10.00.00.0-0.10.00.00.00.00.00.00.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:IncomeTaxesPaid NANA0.10.00.10.00.20.00.20.18.51.03.10.52.0941.671-1.2533.0493.6593.9293.722.59610.2041.3411.4391.1422.113.4394.7941.8461.413.0983.53110.6257.8316.8165.54611.26322.92814.0090.44627.239NANANANA
us-gaap:InterestExpenseDebt ▅█▇█▂▂▁▁▁▁7.59.08.79.15.96.05.75.65.85.8NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:InterestPaidNet ▅█▁▂▅▁▅▁▅▁▅▁▅▁▅9.59999999999999816.10.43.110.20.810.21.010.20.49.80.09.70.29.5NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:NetIncomeLoss ▅▂▅▄▅▆▆▅▅▅▄▅▆▆▇▆▆▅▁▄▆▅▅▄▅██▇▆▅▆▆▅▆▆▆▆▆▅▆▇▇█▅▆▆-35.1-140.0-35.5-58.2-26.9-2.7-4.8-20.7-20.7-34.6-65.0-20.319.4-0.335.80520.7837.131-15.139-168.464-58.273-9.515-16.163-43.08-56.112-33.89773.77961.84950.40520.344-20.104-9.675-9.507-34.5738.253-6.909-12.023-12.277-4.401-31.107-6.623.98625.04665.28-16.7875.1466.332
 us-gaap:NetIncomeLoss us-gaap:ConsolidatedEntities,us-gaap:ConsolidationItems srt:GuarantorSubsidiaries,srt:ReportableLegalEntitiesNANA-17.8-27.4-13.3-3.7-1.2-5.44.10.3-53.7-9.720.48.913.618.2NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:NetIncomeLoss us-gaap:ConsolidatedEntities,us-gaap:ConsolidationItems srt:NonGuarantorSubsidiaries,srt:ReportableLegalEntitiesNANA-11.5-7.5-1.1-26.1-14.1-14.7-21.5-20.9-25.5-4.13.4-4.011.213.7NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:NetIncomeLoss us-gaap:ConsolidatedEntities,us-gaap:ConsolidationItems srt:ParentCompany,srt:ReportableLegalEntitiesNANA-35.5-58.2-26.9-2.8-4.8-20.7-20.7-34.6-65.0-20.319.4-0.335.820.8NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:NetIncomeLoss us-gaap:ConsolidationItems srt:ConsolidationEliminationsNANA29.334.914.429.915.320.117.420.679.213.8-23.8-4.9-24.8-31.9NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:NetIncomeLoss us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome,us-gaap:StatementEquityComponents us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome,us-gaap:AccumulatedDefinedBenefitPlansAdjustment▄▄▂▄▅▄▁▅▅▅▄▅▆▅▇▄▅▅▆▆▆▆▃▅▆▅█▅▅▅▅▅▆▆-1.2-1.3-5.5-1.2-0.8-1.4-7.6-0.7-1.0-0.3-2.70.12.6-0.44.137-1.0840.2060.751.4220.8620.8620.861-4.130.5291.3580.1175.455-0.098-0.5170.1550.3970.5380.840.95NANANANANANANANANANANANA
 us-gaap:NetIncomeLoss us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome,us-gaap:StatementEquityComponents us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome,us-gaap:AccumulatedGainLossNetCashFlowHedgeParent█▆▃█▆▆▃▆▆▆▁▆▆▆0.1-0.0-0.20.10.00.0-0.20.00.00.0-0.30.00.00.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:NetIncomeLoss us-gaap:StatementEquityComponents us-gaap:RetainedEarnings▆▁▆▅▇██▇▇▆-35.1-140.0-35.5-58.2-26.9-2.7-4.8-20.7-20.7-34.6NA-20.319.4-0.3NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:NetIncomeLossAvailableToCommonStockholdersBasic -35.1NANANA-26.9NANANA-20.7NA-65.0-20.317.9-0.332.96319.1326.563-15.139-168.464-58.273-9.515-16.163-43.08-56.112-33.89767.81356.82446.27718.675-20.104-9.675-9.507-34.5737.567-6.909-12.023-12.277-4.401NANA22.06123.005NANA4.7235.808
us-gaap:NetIncomeLossAvailableToCommonStockholdersDiluted -35.1NANANA-26.9NANANA-20.7NANA-20.317.9-0.3NA19.1326.563-15.1NA-58.273-9.515-16.163NA-56.112-33.89767.813NA46.27718.675-20.104NA-9.507-34.5737.567NA-12.023-12.277-4.401-28.599-6.622.06123.005NANANANA
us-gaap:OperatingIncomeLoss ▆▅▅▅▅▆▆▅▅▅▄▅▆▆▇▇▆▆▁▄▆▅▅▄▅██▇▆▅▅▆▅▆▆▅▆▆▅▆▇▇█▆▆▆12.1-36.9-13.2-37.9-25.0-4.4-2.9-25.2-16.3-27.8-68.4-15.621.53.543.28332.47112.9285.176-159.644-55.053-4.941-13.558-28.486-55.526-35.12180.04566.85162.15126.012-14.234-8.631-4.242-23.870.1872.645-13.32-5.0118.412-27.1720.71536.16237.59179.6250.1875.90817.26
us-gaap:OtherComprehensiveIncomeLossNetOfTax NA1.3-12.21.10.71.4-11.80.71.00.3-10.10.12.60.420.2231.0470.1690.712-3.7140.8240.8240.823-10.784-3.62419.3620.078-38.316-0.153-0.1310.09946.8480.48311.1340.895-20.2991.1741.7650.756-56.6870.333NANANANANANA
 us-gaap:OtherComprehensiveIncomeLossNetOfTax us-gaap:ConsolidatedEntities,us-gaap:ConsolidationItems srt:GuarantorSubsidiaries,srt:ReportableLegalEntitiesNANA-7.00.80.41.1-4.80.80.30.6-28.10.52.80.711.91.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:OtherComprehensiveIncomeLossNetOfTax us-gaap:ConsolidatedEntities,us-gaap:ConsolidationItems srt:NonGuarantorSubsidiaries,srt:ReportableLegalEntitiesNANA-2.60.40.50.4-3.20.51.20.34.00.40.30.40.30.3NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:OtherComprehensiveIncomeLossNetOfTax us-gaap:ConsolidatedEntities,us-gaap:ConsolidationItems srt:ParentCompany,srt:ReportableLegalEntitiesNANA-12.21.10.71.4-11.80.71.00.3-10.10.12.60.420.31.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:OtherComprehensiveIncomeLossNetOfTax us-gaap:ConsolidationItems srt:ConsolidationEliminationsNANA9.6-1.2-0.9-1.58.0-1.3-1.5-0.924.1-0.9-3.1-1.1-12.2-1.3NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:OtherComprehensiveIncomeLossNetOfTax us-gaap:StatementEquityComponents us-gaap:AccumulatedOtherComprehensiveIncomeNA1.3-12.21.10.71.4-11.80.71.00.3-10.10.12.60.4NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:OtherNonoperatingIncomeExpense ▆█▅▄▇▇▅▃▁▆▆▆█▂▄▅▁▅▇▄▄▄▁▅▄▆▇▃▅▄▇▅▂▄1.21.90.50.01.31.70.5-0.9-1.71.11.20.72.1-1.1-0.0960.427-1.8760.3841.781-0.157-0.299-0.006-1.6170.1140.0931.0541.414-0.470.3-0.2531.4970.213-1.2840.07NANA0.1610.306NANA-1.1320.677NANANANA
us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax ▇▅▃▄▄▄▅▅▅▆▆▆▅▅▅▄▃▃▂▂▂▂▃▅▇█▇▆▅▄▄▄▂▂▂▂▂▂▂▃▃▂▂▁▁▁528.0444.0389.1392.9401.9421.2435.5438.0473.1490.0486.9481.8470.0454.5433.9400.6388.8365.8339.836333.65326.754318.854383.915454.54523.491587.911551.239500.632458.324420.847401.174399.928331.937321.274317.667304.635323.619326.19318.164345.646366.277326.337316.851279.178287.853285.389
us-gaap:Revenues ▇▅▃▄▄▄▅▅▅▆▆▆▅▅▅▄▃▃▂▂▂▂▃▅▇█▇▆▅▄▄▄▂▂▂▂▂▂▂▃▃▂▂▁▁▁528.0444.0389.1392.9401.9421.2435.5438.0473.1490.0486.9481.8470.0454.5433.9400.6388.8365.8339.836333.65326.754318.854383.915454.54523.491587.911551.239500.632458.324420.847401.174399.928331.937321.274317.667304.635323.619326.19318.164345.646366.277326.337316.851279.178287.853285.389
us-gaap:SellingGeneralAndAdministrativeExpense ▂▅▃▃▃▂▂▃▃▅▂▂▃▃▃▄▂▃▃▂▂▂▂▃▂▃▅▃▃▂█▅▅▅▃▂▁▂▂▁▇▃▃▄▃▃8.716.111.811.011.88.99.211.611.914.78.78.812.010.711.39813.9949.35210.70210.9619.7339.9459.6258.56611.56610.01211.97116.36912.14610.61810.06221.60214.42215.15416.29910.5719.1827.1518.4598.9167.9518.55710.60911.10112.48610.96412.251
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
us-gaap:Assets ▁▁▁▁▃▃▂▂▂▃▃▃▃▃▃▃▃▃▃▄▄▅▅▆▇█▇▆▅▅▅▆▆▅▅▅▅▅▅▆▆▆▆1405.41363.41399.61405.41524.01591.11499.71491.81515.31530.41537.51613.71616.91580.81581.6411563.4631525.6291525.8071540.3271688.7161719.5881723.6051752.4681906.7011989.2382083.0482014.0351839.4811776.481786.8551810.1961859.6311851.1751791.1151776.3261783.4391779.1011797.4261811.0941863.671899.8421921.1811923.056NANANA
us-gaap:LiabilitiesAndStockholdersEquity ▁▁▁▁▃▃▂▂▂▃▃▃▃▃▃▃▃▃▃▄▄▅▅▆▇█▇▆▅▅▅▆▆▅▅▅▅▅▅▆▆▆▆1405.41363.41399.61405.41524.01591.11499.71491.81515.31530.41537.51613.71616.91580.81581.6411563.4631525.6291525.8071540.3271688.7161719.5881723.6051752.4681906.7011989.2382083.0482014.0351839.4811776.481786.8551810.1961859.6311851.1751791.1151776.3261783.4391779.1011797.4261811.0941863.671899.8421921.1811923.056NANANA
us-gaap:StockholdersEquity ▁▁▃▃▃▄▄▄▄▄▄▅▅▅▅▄▄▄▄▆▆▆▇▇▇█▇▇▆▆▆▆▆▆▆▇▇▇▇████370.4408.3546.1592.4648.7673.8675.0689.9709.4728.1762.2833.5853.1830.4829.643773.094750.761742.744756.655937.524994.4351002.8511017.871071.271116.541138.9471091.1471054.3311003.633983.1161002.812965.521968.895992.009982.6431009.6511020.2991030.7441038.2771132.9691177.8221168.6921154.516NANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
us-gaap:AssetsCurrent ▂▁▂▁▄▅▃▂▃▂▃▆▆▅▅▃▂▁▁▁▂▁▁▄▆█▆▄▂▂▂▃▄▃▃▂▂▃▃▄▅▅▅478.0440.9456.0443.3531.4583.8487.3474.1501.6483.3506.7590.4606.9568.6553.674510.794457.731438.394440.622432.452450.348435.241448.057543.455599.547672.674599.24522.12453.344456.194471.061512.209523.306509.306487.397465.678464.788486.445488.32526.019558.042582.274577.078NANANA
us-gaap:CashAndCashEquivalentsAtCarryingValue ▁▁▃▃▅▄▂▁▁▁▂▃▄▄▅▅▄▄▄▄▄▄▄▄▅▆▅▄▂▂▃▄▄▅▅▅▄▅▅▆▆██▇▇▆9.026.381.681.4174.1147.638.922.525.722.238.973.4124.0130.8167.211174.213130.673125.895132.403117.593129.384126.461115.393122.976167.408226.431163.242133.4161.38452.49884.088140.801127.531195.471183.976173.375156.512182.545183.401216.395232.401293.487304.296265.243256.264213.739
us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents ▁▂▄▄█▇▂▂▂▂▂▄▆▆██▆▆▆10.227.584.385.1177.8149.439.723.326.523.039.774.2124.8131.6168.0175.1131.5126.7133.5NANANA116.2NANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:AccountsReceivableNetCurrent ▆▅▅▅▃▅▆▇██▇██▇▄▄▄▃▂▂▂▂▁▁▁▁▆▅▅▄▅▅▇▅▅▄▆▅▄▅▅▃▄67.057.451.050.635.952.970.181.992.390.982.591.496.683.443.07140.36742.47336.22512.43211.18714.30412.6689.4758.6139.8073.46476.16550.57652.25345.61956.18451.24784.06752.31250.66744.32771.93650.53147.64752.06754.83836.38343.903NANANA
us-gaap:InventoryNet ▆▅▅▄▅▆▆▆▆▆▇█▇▆▆▄▄▄▃▃▃▃▃▅▆▅▅▄▄▄▃▃▃▁▁▁▁▁▁▁▂▁▁331.5303.0291.1267.5275.0317.6320.6322.3339.2327.4343.8390.4363.0330.7317.469261.756254.611244.72233.563233.288231.832220.502231.872298.859318.422297.814283.48241.75243.648252.099239.615231.505224.707156.815159.925159.968158.538170.302171.961165.714187.388163.971155.908NANANA
us-gaap:PrepaidExpenseAndOtherAssetsCurrent ▂▂▁▁▁▁▁▃▃▂▂▁▂▁▁▃▂▂▃▅▄▄▇▆▆▃▄▄▄▅▅▇▇▇▅█▇▇▇▇18.017.912.914.514.613.412.223.322.218.218.013.915.914.214.70921.76118.62418.96822.2131.82827.95329.62242.41236.6236.23623.80929.76829.10125.3235.20132.27640.70841.44641.16334.97548.25343.13143.8540.64644.491NANA18.292NANANA
us-gaap:MachineryAndEquipmentGross NANA1506.5NANANA1467.0NANANA1449.5NANANA1398.687NANANA1374.551NANANA1349.731NANANA1395.221NANANA1464.532NANANA1404.928NANANA1387.01NANANANANANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
 us-gaap:NoncurrentAssets us-gaap:StatementGeographical cenx:OtherNANA68.6NANANA75.3NANANA76.5NANANA74.957NANANA78.701NANANA94.421NANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:NoncurrentAssets us-gaap:StatementGeographical country:ISNANA511.8NANANA518.0NANANA554.3NANANA582.981NANANA625.897NANANA801.268NANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:NoncurrentAssets us-gaap:StatementGeographical country:USNANA363.3NANANA419.1NANANA396.0NANANA370.029NANANA395.107NANANA408.722NANANA487.536NANANA392.424NANANA368.897NANANANANANANANANANANA
us-gaap:PropertyPlantAndEquipmentGross NANA1902.5NANANA1890.9NANANA1874.9NANANA1794.762NANANA1768.565NANANA1891.383NANANA2033.146NANANA2042.263NANANA1917.729NANANA1882.744NANANA1857.618NANANA
us-gaap:ConstructionInProgressGross NANA15.8NANANA44.9NANANA46.3NANANA22.517NANANA21.106NANANA173.418NANANA182.393NANANA221.101NANANA175.283NANANA162.161NANANANANANANA
us-gaap:AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment NANA1022.1NANANA941.7NANANA907.6NANANA822.846NANANA742.28NANANA659.127NANANA741.928NANANA794.602NANANA729.515NANANA664.519NANANA600.648NANANA
us-gaap:PropertyPlantAndEquipmentNet ▁▁▁▂▂▂▂▂▂▃▃▃▂▂▃▃▃▃▄▆▆▇▇▇███▇▇▇▇▇▇▆▆▆▇▇▇▇▇▇▇868.8867.4880.4899.7919.0935.4949.2950.1951.5960.1967.3961.5947.9955.1971.916984.9481000.5031012.5641026.2851185.1011197.6041215.2221232.2561251.4761263.8611285.8451291.2181221.7051230.0141239.8931247.6611239.2011230.0311180.771188.2141197.6441208.0291206.1061218.2251224.3191238.6511246.531256.97NANANA
 us-gaap:InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures us-gaap:ConsolidatedEntities,us-gaap:ConsolidationItems srt:GuarantorSubsidiaries,srt:ReportableLegalEntitiesNANA65.465.965.163.362.757.754.254.854.553.7NANA54.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures us-gaap:ConsolidatedEntities,us-gaap:ConsolidationItems srt:ParentCompany,srt:ReportableLegalEntitiesNANA495.5533.8568.3583.4609.5625.1634.8648.1668.3772.3NANA751.8NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures us-gaap:ConsolidationItems srt:ConsolidationEliminationsNANA-560.9-599.7-633.4-646.7-672.2-682.8-689.0-702.9-722.8-826.0NANA-805.8NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:OperatingLeaseRightOfUseAsset NANA24.9NANANA25.224.224.324.60.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:OtherAssetsNoncurrent ▃▂▃▃▄▃▃▁▁▃▃▃▃▃▂▃▃▄▄▄▄▄▄▇███▆▅▅▅▇▆▆▆█▆▆▆▇▆▅▅58.655.161.561.169.766.862.742.037.962.463.561.862.157.156.05167.72167.39574.84973.4271.16371.63673.14272.155111.77125.83124.529123.57795.65693.12290.76891.474108.22197.838101.039100.715120.117106.284104.875104.549113.332100.05585.20582.954NANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
us-gaap:AccruedLiabilitiesCurrent ▃▃▃▄▅▂▄▄▃▃▂▄▄▄▃▃▂▃▂▃▂▂▂▄▄██▂▂▂▄▄▅▂▁▂▁▂▁▃▂▂▁54.862.359.469.576.950.665.566.155.959.252.565.964.468.061.39856.73245.67958.09450.159.38248.47950.16948.82271.46567.162107.374104.64646.00745.18251.64469.46672.92181.17249.00140.09952.91344.71648.91740.77658.70449.22546.53541.495NANANA
us-gaap:LiabilitiesCurrent █▇▃▂▄▅▃▃▂▃▃▃▃▂▂▂▁▂▂▁▁▁▁▃▄▆▅▃▃▃▄▅▅▂▂▂▂▂▂▃▂▃▄394.4364.3240.3201.2249.6284.9233.7212.3204.6229.6224.3230.5209.8197.2190.517195.68175.484185.544179.16174.9165.265158.798167.319232.108267.72315.373296.324217.329209.783242.242247.763278.088278.219201.49181.704198.876182.053189.45193.365213.005200.092242.197254.86NANANA
us-gaap:OperatingLeaseLiabilityCurrent NANA1.6NANANA2.8NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:OtherLiabilitiesCurrent us-gaap:CounterpartyName cenx:RavenswoodRetireeMedicalBenefitsChangesNANA2.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
us-gaap:LiabilitiesNoncurrent █▅▇▆▇█▅▅▆▄▃▃▃▃▄▆▆▆▆▅▄▄▄▆▆▇▇▄▄▄▄▇▆▆▆▄▅▅▅▁▂▁▁640.6590.8613.2611.8625.7632.4591.0589.6601.3572.7551.0549.7554.0553.2561.481594.689599.384597.519604.512576.292559.888561.956567.279603.323604.978628.728626.564567.821563.064561.497559.621616.022604.061597.616611.979574.912576.749577.232579.452517.696521.928510.292513.68NANANA
 us-gaap:SecuredLongTermDebt us-gaap:DebtInstrument,us-gaap:LongtermDebtType cenx:SeniorSecuredNotes120,us-gaap:SeniorNotesNANA243.1NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:SecuredLongTermDebt us-gaap:DebtInstrument,us-gaap:LongtermDebtType cenx:SeniorSecuredNotes75,us-gaap:SeniorNotes245.4NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:SecuredLongTermDebt us-gaap:DebtInstrument,us-gaap:LongtermDebtType cenx:SeniorSecuredNotesDueJune012025,us-gaap:LongTermDebtNA243.4243.1242.8NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:DeferredIncomeTaxLiabilitiesNet ▁▆▆▇▇▇▇▇███42.886.389.294.694.794.795.198.7100.5102.1104.3NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent us-gaap:RetirementPlanType us-gaap:OtherPostretirementBenefitPlansDefinedBenefitNANA101.5NANANA100.7NANANA101.2NANANA113.305NANANA126.355NANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent us-gaap:RetirementPlanType us-gaap:PensionPlansDefinedBenefitNANA65.2NANANA60.8NANANA50.9NANANA38.929NANANA49.493NANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:OtherLiabilitiesNoncurrent ▄▇▄▄▄▄▄▄▄▄▄▅▆▅▆▆▇▇██▅▅▅▄▄▄▅▃▃▃▃▃▃▁▃▃▃▃▃▃▃▂▃47.567.344.846.247.847.142.445.447.948.446.050.857.654.557.92762.09466.8464.60872.02672.3353.10251.79953.00947.5846.59647.9953.27238.87937.41636.98437.74337.18437.05625.27840.16239.7239.6939.46640.00540.73941.66234.94237.612NANANA
us-gaap:OperatingLeaseLiabilityNoncurrent ████▇▇█▇██▁23.123.224.323.421.721.922.821.923.522.80.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearTwo NANA3.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearThree NANA2.7NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFour NANA2.7NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFive NANA2.7NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive NANA29.1NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
us-gaap:StockholdersEquity ▁▁▃▃▃▄▄▄▄▄▄▅▅▅▅▄▄▄▄▆▆▆▇▇▇█▇▇▆▆▆▆▆▆▆▇▇▇▇████370.4408.3546.1592.4648.7673.8675.0689.9709.4728.1762.2833.5853.1830.4829.643773.094750.761742.744756.655937.524994.4351002.8511017.871071.271116.541138.9471091.1471054.3311003.633983.1161002.812965.521968.895992.009982.6431009.6511020.2991030.7441038.2771132.9691177.8221168.6921154.516NANANA
us-gaap:CommonStockValue ███████████▁▁▁▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▃▃▃▃▃▃▃▃▃▃▃▃▃1.01.01.01.01.01.01.01.01.01.01.00.90.90.90.9470.9450.9450.9440.9440.9420.9420.9420.9420.9410.9410.9390.9390.9370.9360.9360.9350.9350.9340.9340.9330.9330.9330.9320.9320.9320.9320.9310.928NANANA
us-gaap:AdditionalPaidInCapital ▇██▇▇▇▇▆▆▆▆▅▅▅▄▄▄▄▄▄▄▄▄▃▃▃▃▂▂▂▂▂▂▂▂▂▂▂▂▂▂▁▁2527.02530.92530.02528.42527.62526.62526.52524.82524.32523.32523.02519.52518.82518.12517.3852516.8662516.3632515.6472515.1312514.7652514.2272513.9522513.6312513.1682512.6822510.6652510.2612509.6312509.1862508.8822508.5742508.4562507.9962507.6712507.4542507.2542507.0532506.9872506.8422506.6552506.4352504.3912503.907NANANA
us-gaap:RetainedEarningsAccumulatedDeficit ▁▁▃▃▃▄▄▄▄▄▄▅▅▅▅▅▄▄▅▆▇▇▇▇██▇▇▆▆▆▆▆▇▇▇▇▇▇▇▇▇▇-1954.9-1919.8-1779.8-1744.2-1686.0-1659.1-1656.4-1651.6-1630.9-1610.2-1576.8-1511.9-1491.6-1511.0-1510.672-1546.477-1567.26-1574.391-1559.252-1381.729-1323.456-1313.941-1297.778-1254.698-1212.566-1178.669-1252.448-1314.297-1364.702-1385.046-1364.942-1355.267-1350.949-1316.376-1324.629-1317.72-1305.697-1293.42-1289.019-1257.912-1251.312-1275.298-1300.344NANANA
us-gaap:AccumulatedOtherComprehensiveIncomeLossNetOfTax ▃▃▃▄▄▄▄▅▅▅▅▅▅▅▅▄▄▄▄▄▄▄▄▄▅▃▃▅▅▅▅▂▂▁▁▂▂▂▂▆▆▇█-116.4-117.5-118.8-106.5-107.6-108.4-109.8-98.0-98.7-99.7-98.7-88.7-88.7-91.3-91.742-111.965-113.012-113.181-113.893-110.179-111.003-111.827-112.65-101.866-98.242-117.604-117.682-92.017-91.864-91.733-91.832-138.68-139.163-150.297-151.192-130.893-132.067-133.832-134.588-77.901-78.234-61.333-49.976NANANA
us-gaap:TreasuryStockValue █████████████████████████▇▃▃▃▃▃▃▃▃▃▃▃▃▂▁86.386.386.386.386.386.386.386.386.386.386.386.386.386.386.27686.27686.27686.27686.27686.27686.27686.27686.27686.27686.27676.38549.92449.92449.92449.92449.92449.92449.92449.92449.92449.92449.92449.92445.89138.806NANA0.0NANANA
us-gaap:AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue ▂▃▄▂▃▁▄▂▃▁█▂▂▂0.70.91.60.81.10.11.60.51.00.33.60.70.70.7NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
us-gaap:NetCashProvidedByUsedInOperatingActivities ▂▂▄▂▅▅▅▅▄▃▃▃▄▃▄▆▄▃▅▄▄▄▄▁▄█▇▇▅▃▃▅▄▅▄▅▄▄▃▅▃▄▅▅▆▅-38.1-49.89.600000000000003-38.337.034.622.121.2-4.1-21.5-10.1-28.62.6-33.01.09247.57414.437-11.34422.591-8.0218.714.903-0.643-77.807-5.951116.26798.69789.08619.369-10.741-22.7419.4820.57522.40116.05422.7-6.5134.898-14.0327.229-12.505-3.6331.17828.250.47421.658
 us-gaap:NetCashProvidedByUsedInOperatingActivities us-gaap:ConsolidatedEntities,us-gaap:ConsolidationItems srt:GuarantorSubsidiaries,srt:ReportableLegalEntitiesNANA-6.3-45.532.734.16.446.14.2-5.3-19.02.423.9-26.8-21.3NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:NetCashProvidedByUsedInOperatingActivities us-gaap:ConsolidatedEntities,us-gaap:ConsolidationItems srt:NonGuarantorSubsidiaries,srt:ReportableLegalEntitiesNANA13.711.712.913.530.3-3.49.71.410.7-22.7-5.220.634.4NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:NetCashProvidedByUsedInOperatingActivities us-gaap:ConsolidatedEntities,us-gaap:ConsolidationItems srt:ParentCompany,srt:ReportableLegalEntitiesNANA2.2-4.5-8.6-13.0-14.6-21.5-18.0-17.6-1.8-8.3-16.1-26.8-9.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:NetCashProvidedByUsedInInvestingActivities ▄▅▆▆▅▅▅▅▆▅▃▃▅▅▅▅▅▆▅▅▅▅▅█▃▃▁▅▅▅▄▄▂▅▅▅▄▆▅▅▆▅▆▄▅▅-18.5-7.4-0.4-1.9-3.6-5.9-9.4-16.6-2.2-10.6-33.6-36.3-9.5-3.5-8.217-4.075-9.8564.793-7.781-3.77-5.777-3.835-6.9433.375-36.159-33.639-69.119-14.48-10.606-14.852-23.248-22.869-60.151-10.906-5.453-5.837-19.52-1.721-11.879-4.48-1.357-7.1797.875-19.221-7.972-6.153
 us-gaap:NetCashProvidedByUsedInInvestingActivities us-gaap:ConsolidatedEntities,us-gaap:ConsolidationItems srt:GuarantorSubsidiaries,srt:ReportableLegalEntitiesNANA-12.617.0-29.6-35.025.6-33.2-21.3-24.5-12.4-2.75.1-0.430.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:NetCashProvidedByUsedInInvestingActivities us-gaap:ConsolidatedEntities,us-gaap:ConsolidationItems srt:NonGuarantorSubsidiaries,srt:ReportableLegalEntitiesNANA-1.31.4-0.6-0.37.8-0.63.3-3.1-4.4-3.1-2.1-1.6-4.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:NetCashProvidedByUsedInInvestingActivities us-gaap:ConsolidatedEntities,us-gaap:ConsolidationItems srt:ParentCompany,srt:ReportableLegalEntitiesNANA-8.4-23.87.530.452.612.9-7.0-15.8-18.322.538.3-25.339.3NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:NetCashProvidedByUsedInInvestingActivities us-gaap:ConsolidationItems srt:ConsolidationEliminationsNANA21.93.519.1-1.0-95.44.322.832.81.5-53.0-50.823.8-73.6NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:NetCashProvidedByUsedInFinancingActivities ▆▄▃▁▃█▄▃▄▅▄▅▄▄▄▄▄▄▄▄▄▄▄▄▃▃▄▄▄▃▃▅▃▄▄▄▄▄▃▂▁▄▄▄39.30.4-10.0-52.5-5.081.03.7-7.89.815.49.214.30.10.10.1230.0410.1970.0430.00.00.00.00.00.0-16.913-19.4390.254-2.580.123-5.997-10.72516.657-8.3640.00.00.00.0-4.033-7.085-38.755-47.2240.00.00.0NANA
us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect ▄▂▄▁▅█▅▄▄▄▃▂▄▃▄▆▄▄-17.3-56.8-0.8-92.728.4109.716.4-3.23.5-16.7-34.5-50.6-6.8-36.4-7.143.64.8-6.8NANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect us-gaap:ConsolidatedEntities,us-gaap:ConsolidationItems srt:GuarantorSubsidiaries,srt:ReportableLegalEntitiesNANA0.00.00.11.00.10.1-0.20.10.3-0.20.00.00.1NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect us-gaap:ConsolidatedEntities,us-gaap:ConsolidationItems srt:NonGuarantorSubsidiaries,srt:ReportableLegalEntitiesNANA1.57.97.226.417.5-4.23.0-16.6-8.9-49.1-25.619.4-0.9NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect us-gaap:ConsolidatedEntities,us-gaap:ConsolidationItems srt:ParentCompany,srt:ReportableLegalEntitiesNANA-2.3-100.621.182.3-1.20.90.7-0.2-25.9-1.318.8-55.8-6.3NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
us-gaap:DepreciationDepletionAndAmortization ▆▆▆▆▅▅▅▅▄█▇█▇▆▆▆▆▆▆▆▆▆█▅▄▄▄▄▄▄▄▅▁▂▂▂▂▂▂▂▂▃▃▃▂▂20.920.921.321.320.220.220.219.918.824.322.623.922.121.521.15820.86921.28420.93821.47420.80221.24421.2624.30219.40618.27818.13117.94717.64117.37517.76817.48819.92513.46915.68815.64515.63715.63615.65215.61515.51515.13415.9316.23715.80815.72715.778
us-gaap:IncreaseDecreaseInAccountsReceivable ▆▆▆▆▄▄▅▅▅▆▅▅▆█▆▅▆▇▆▅▆▆▆▅▆▁▇▅▆▅▆▃▇▆▆▄▇▆▆▆▄▆▆▅▅▆9.66.40.414.6-16.9-17.2-1.7-10.0-9.18.4-8.9-5.213.240.32.704-2.1056.24723.7931.245-3.1171.6363.1930.863-2.6966.343-72.70225.589-1.6776.635-10.5664.938-32.8231.8851.9985.857-27.60921.4052.88411.9082.771-18.4557.527.47-2.286-1.3012.314
us-gaap:IncreaseDecreaseInInventories ▇▆▇▅▄▆▅▅▆▄▅▇▇▆▇▆▆▅▅▅▆▄▁▅▇▆▆▅▅▆▅▅▆▅▅▅▅▄█▆▄▅▇▅▅▅28.611.827.8-3.9-18.810.41.3-14.625.3-16.4-16.036.532.310.043.4437.14512.2694.677-2.1843.73615.177-17.648-91.288-14.23946.29614.33515.624-1.897-8.59111.377-1.1080.51419.6062.728-0.044-6.77-6.33-18.7159.0888.195-23.54-7.92431.7573.414-2.022-9.14
us-gaap:IncreaseDecreaseInOtherOperatingCapitalNet ▅▄▄▄▄▄▄▄▄▄▂▅▃▅▅▃▂▅▄▄▄▄▃▃▆▄▃▄▄▄▁▆▂▃▁▆▄▄▇▁▄▃█▃▄▃3.60.72.9-2.0-2.2-1.11.50.6-1.70.6-7.65.0-4.13.85.62-6.208-7.5793.585-1.102-1.456-2.191.648-2.48-3.3218.3280.604-6.1030.9172.56-0.064-15.24611.538-11.335-2.558-13.7812.88-0.369-0.33517.714-13.482.459-2.99821.11-2.6951.32-6.093
us-gaap:NetCashProvidedByUsedInOperatingActivities ▂▂▄▂▅▅▅▅▄▃▃▃▄▃▄▆▄▃▅▄▄▄▄▁▄█▇▇▅▃▃▅▄▅▄▅▄▄▃▅▃▄▅▅▆▅-38.1-49.89.600000000000003-38.337.034.622.121.2-4.1-21.5-10.1-28.62.6-33.01.09247.57414.437-11.34422.591-8.0218.714.903-0.643-77.807-5.951116.26798.69789.08619.369-10.741-22.7419.4820.57522.40116.05422.7-6.5134.898-14.0327.229-12.505-3.6331.17828.250.47421.658
 us-gaap:NetCashProvidedByUsedInOperatingActivities us-gaap:ConsolidatedEntities,us-gaap:ConsolidationItems srt:GuarantorSubsidiaries,srt:ReportableLegalEntitiesNANA-6.3-45.532.734.16.446.14.2-5.3-19.02.423.9-26.8-21.3NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:NetCashProvidedByUsedInOperatingActivities us-gaap:ConsolidatedEntities,us-gaap:ConsolidationItems srt:NonGuarantorSubsidiaries,srt:ReportableLegalEntitiesNANA13.711.712.913.530.3-3.49.71.410.7-22.7-5.220.634.4NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:NetCashProvidedByUsedInOperatingActivities us-gaap:ConsolidatedEntities,us-gaap:ConsolidationItems srt:ParentCompany,srt:ReportableLegalEntitiesNANA2.2-4.5-8.6-13.0-14.6-21.5-18.0-17.6-1.8-8.3-16.1-26.8-9.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:NetIncomeLoss ▅▂▅▄▅▆▆▅▅▅▄▅▆▆▇▆▆▅▁▄▆▅▅▄▅██▇▆▅▆▆▅▆▆▆▆▆▅▆▇▇█▅▆▆-35.1-140.0-35.5-58.2-26.9-2.7-4.8-20.7-20.7-34.6-65.0-20.319.4-0.335.80520.7837.131-15.139-168.464-58.273-9.515-16.163-43.08-56.112-33.89773.77961.84950.40520.344-20.104-9.675-9.507-34.5738.253-6.909-12.023-12.277-4.401-31.107-6.623.98625.04665.28-16.7875.1466.332
 us-gaap:NetIncomeLoss us-gaap:ConsolidatedEntities,us-gaap:ConsolidationItems srt:GuarantorSubsidiaries,srt:ReportableLegalEntitiesNANA-17.8-27.4-13.3-3.7-1.2-5.44.10.3-53.7-9.720.48.913.618.2NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:NetIncomeLoss us-gaap:ConsolidatedEntities,us-gaap:ConsolidationItems srt:NonGuarantorSubsidiaries,srt:ReportableLegalEntitiesNANA-11.5-7.5-1.1-26.1-14.1-14.7-21.5-20.9-25.5-4.13.4-4.011.213.7NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:NetIncomeLoss us-gaap:ConsolidatedEntities,us-gaap:ConsolidationItems srt:ParentCompany,srt:ReportableLegalEntitiesNANA-35.5-58.2-26.9-2.8-4.8-20.7-20.7-34.6-65.0-20.319.4-0.335.820.8NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:NetIncomeLoss us-gaap:ConsolidationItems srt:ConsolidationEliminationsNANA29.334.914.429.915.320.117.420.679.213.8-23.8-4.9-24.8-31.9NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:NetIncomeLoss us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome,us-gaap:StatementEquityComponents us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome,us-gaap:AccumulatedDefinedBenefitPlansAdjustment▄▄▂▄▅▄▁▅▅▅▄▅▆▅▇▄▅▅▆▆▆▆▃▅▆▅█▅▅▅▅▅▆▆-1.2-1.3-5.5-1.2-0.8-1.4-7.6-0.7-1.0-0.3-2.70.12.6-0.44.137-1.0840.2060.751.4220.8620.8620.861-4.130.5291.3580.1175.455-0.098-0.5170.1550.3970.5380.840.95NANANANANANANANANANANANA
 us-gaap:NetIncomeLoss us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome,us-gaap:StatementEquityComponents us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome,us-gaap:AccumulatedGainLossNetCashFlowHedgeParent█▆▃█▆▆▃▆▆▆▁▆▆▆0.1-0.0-0.20.10.00.0-0.20.00.00.0-0.30.00.00.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:NetIncomeLoss us-gaap:StatementEquityComponents us-gaap:RetainedEarnings▆▁▆▅▇██▇▇▆-35.1-140.0-35.5-58.2-26.9-2.7-4.8-20.7-20.7-34.6NA-20.319.4-0.3NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
us-gaap:NetCashProvidedByUsedInInvestingActivities ▄▅▆▆▅▅▅▅▆▅▃▃▅▅▅▅▅▆▅▅▅▅▅█▃▃▁▅▅▅▄▄▂▅▅▅▄▆▅▅▆▅▆▄▅▅-18.5-7.4-0.4-1.9-3.6-5.9-9.4-16.6-2.2-10.6-33.6-36.3-9.5-3.5-8.217-4.075-9.8564.793-7.781-3.77-5.777-3.835-6.9433.375-36.159-33.639-69.119-14.48-10.606-14.852-23.248-22.869-60.151-10.906-5.453-5.837-19.52-1.721-11.879-4.48-1.357-7.1797.875-19.221-7.972-6.153
 us-gaap:NetCashProvidedByUsedInInvestingActivities us-gaap:ConsolidatedEntities,us-gaap:ConsolidationItems srt:GuarantorSubsidiaries,srt:ReportableLegalEntitiesNANA-12.617.0-29.6-35.025.6-33.2-21.3-24.5-12.4-2.75.1-0.430.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:NetCashProvidedByUsedInInvestingActivities us-gaap:ConsolidatedEntities,us-gaap:ConsolidationItems srt:NonGuarantorSubsidiaries,srt:ReportableLegalEntitiesNANA-1.31.4-0.6-0.37.8-0.63.3-3.1-4.4-3.1-2.1-1.6-4.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:NetCashProvidedByUsedInInvestingActivities us-gaap:ConsolidatedEntities,us-gaap:ConsolidationItems srt:ParentCompany,srt:ReportableLegalEntitiesNANA-8.4-23.87.530.452.612.9-7.0-15.8-18.322.538.3-25.339.3NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:NetCashProvidedByUsedInInvestingActivities us-gaap:ConsolidationItems srt:ConsolidationEliminationsNANA21.93.519.1-1.0-95.44.322.832.81.5-53.0-50.823.8-73.6NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:PaymentsToAcquirePropertyPlantAndEquipment ▄▂▁▁▂▂▅▄▃▃▇█▃▂▂▂▃▃▃▂▂▂▄▃▄▃▄▃▂▃▄▄▂▃▂▂▁▁▃▂▂▁▂▁▁▁18.57.41.91.93.66.019.716.612.710.633.736.39.53.58.2494.7479.7989.0458.8175.3933.8993.83516.62511.48815.62710.9614.69410.1077.0589.714.53915.4297.2019.3647.2784.2343.2662.8999.2323.5154.2253.1286.8632.3662.040.972
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
us-gaap:NetCashProvidedByUsedInFinancingActivities ▆▄▃▁▃█▄▃▄▅▄▅▄▄▄▄▄▄▄▄▄▄▄▄▃▃▄▄▄▃▃▅▃▄▄▄▄▄▃▂▁▄▄▄39.30.4-10.0-52.5-5.081.03.7-7.89.815.49.214.30.10.10.1230.0410.1970.0430.00.00.00.00.00.0-16.913-19.4390.254-2.580.123-5.997-10.72516.657-8.3640.00.00.00.0-4.033-7.085-38.755-47.2240.00.00.0NANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
 us-gaap:DebtInstrumentInterestRateStatedPercentage us-gaap:DebtInstrument,us-gaap:LongtermDebtType cenx:EOnContingentObligation,us-gaap:LongTermDebtNANA1.094e-05NANANA1.094e-07NANANA1.094e-07NANANA1.094e-07NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:DebtInstrumentInterestRateStatedPercentage us-gaap:DebtInstrument,us-gaap:LongtermDebtType cenx:SeniorSecuredNotesDueJune012025,us-gaap:LongTermDebtNANA1.2e-05NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA

Common Stock Value

us-gaap:CommonStockValue

us-gaap:CommonStockValue


Common
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
Value1.01.01.01.01.01.01.01.01.01.01.00.90.90.90.9470.9450.9450.9440.9440.9420.9420.9420.9420.9410.9410.9390.9390.9370.9360.9360.9350.9350.9340.9340.9330.9330.9330.9320.9320.9320.9320.9310.928
Percentage of CommonStockValue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.00.00.00.00.10.10.10.10.10.10.10.10.10.10.10.10.10.00.00.0

us-gaap:CommonStockValue us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

srt:NonGuarantorSubsidiaries, srt:ReportableLegalEntities


Common
Period End2020-12-312020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-12-31
Value0.10.00.10.10.10.10.10.10.10.1
Percentage of CommonStockValue10.00.010.010.010.010.010.010.011.110.6
Percentage of Assets0.00.00.00.00.00.00.00.00.00.0
Percentage of Assets srt:NonGuarantorSubsidiaries srt:ReportableLegalEntities0.00.00.00.00.00.00.00.00.00.0

srt:ParentCompany, srt:ReportableLegalEntities


Common
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-12-31
Value1.01.01.01.01.01.01.01.01.00.90.9
Percentage of CommonStockValue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.095.0
Percentage of Assets0.10.10.10.10.10.10.10.10.10.10.1
Percentage of Assets srt:ParentCompany srt:ReportableLegalEntities0.10.10.10.10.10.10.10.10.10.10.1

us-gaap:CommonStockValue us-gaap:ConsolidationItems

srt:ConsolidationEliminations


Common
Period End2020-12-312020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-12-31
Value-0.10.0-0.1-0.1-0.1-0.1-0.1-0.1-0.1-0.1
Percentage of CommonStockValue-10.00.0-10.0-10.0-10.0-10.0-10.0-10.0-11.1-10.6
Percentage of Assets-0.00.0-0.0-0.0-0.0-0.0-0.0-0.0-0.0-0.0
Percentage of Assets srt:ConsolidationEliminations0.0-0.00.00.00.00.00.00.00.00.0

Weighted Average Number Of Diluted Shares Outstanding

us-gaap:WeightedAverageNumberOfDilutedSharesOutstanding

us-gaap:WeightedAverageNumberOfDilutedSharesOutstanding


Weighted
Period End2021-06-302020-06-302019-06-302018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-09-302012-06-302012-03-312011-09-302011-06-302011-03-31
Value908988878887888887878787868689898988888889888888929393
Percentage of WeightedAverageNumberOfDilutedSharesOutstanding100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Weighted Average Number Of Shares Outstanding Basic

us-gaap:WeightedAverageNumberOfSharesOutstandingBasic

us-gaap:WeightedAverageNumberOfSharesOutstandingBasic


Weighted
Period End2021-06-302020-06-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-09-302012-06-302012-03-312011-09-302011-06-30
Value90898888878787878787878787868688888888880.576510.4159580.406070.3957910.3455240.3233960.343148
Percentage of WeightedAverageNumberOfSharesOutstandingBasic100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Weighted Average Number Of Share Outstanding Basic And Diluted

us-gaap:WeightedAverageNumberOfShareOutstandingBasicAndDiluted

us-gaap:WeightedAverageNumberOfShareOutstandingBasicAndDiluted


Weighted
Period End2021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-03-312017-03-312016-09-302016-03-312015-09-30
Value90898989888888878787878786
Percentage of WeightedAverageNumberOfShareOutstandingBasicAndDiluted100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount

us-gaap:AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount

us-gaap:AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount


Antidilutive
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-30
Value2.42.21.70.60.40.70.70.61.30.61.40.5350.4325061.21.8221.800096
Percentage of AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount us-gaap:AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecurities

cenx:ConvertibleSeniorNotes


Antidilutive
Period End2021-06-30
Value4.8
Percentage of AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount200.0

us-gaap:ConvertiblePreferredStock


Antidilutive
Period End2021-06-302021-03-312020-06-30
Value6.36.46.6
Percentage of AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount262.5290.91100.0

Earnings Per Share Basic

us-gaap:EarningsPerShareBasic

us-gaap:EarningsPerShareBasic


Earnings
Period End2021-06-302020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302011-09-302011-06-302011-03-312010-09-302010-06-302010-03-31
Value-0.39-0.4-0.65-0.3-0.03-0.05-0.23-0.23-0.39-0.74-0.230.200.380.220.08-0.17-1.93-0.67-0.11-0.19-0.5-0.65-0.390.760.640.520.21-0.23-0.11-0.11-0.390.09-0.08-0.14-0.14-0.070.240.25-0.180.050.06
Percentage of EarningsPerShareBasic100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Earnings Per Share Diluted

us-gaap:EarningsPerShareDiluted

us-gaap:EarningsPerShareDiluted


Earnings
Period End2021-06-302020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302011-09-302011-06-302011-03-312010-09-302010-06-302010-03-31
Value-0.39-0.4-0.65-0.3-0.03-0.05-0.23-0.23-0.39-0.74-0.230.200.370.220.07-0.17-1.93-0.67-0.11-0.19-0.5-0.65-0.390.760.630.520.21-0.23-0.11-0.11-0.390.09-0.08-0.14-0.14-0.070.240.25-0.180.050.06
Percentage of EarningsPerShareDiluted100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Earnings Per Share Basic And Diluted

us-gaap:EarningsPerShareBasicAndDiluted

us-gaap:EarningsPerShareBasicAndDiluted


Earnings
Period End2021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-03-312016-12-312016-09-302016-03-312015-12-312015-09-302015-03-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value-1.55-0.4-0.65-0.3-0.03-0.05-0.23-0.23-0.39-0.75-0.230.20-0.17-1.94-0.67-0.19-0.49-0.650.760.520.21-0.23-0.11-0.11-0.390.09-0.08-0.14-0.14-0.05-0.35-0.070.240.250.65-0.180.050.06
Percentage of EarningsPerShareBasicAndDiluted100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Comprehensive Income Net Of Tax

us-gaap:ComprehensiveIncomeNetOfTax

us-gaap:ComprehensiveIncomeNetOfTax


Comprehensive
Period End2021-06-302020-06-30
Value-34000000.0-26200000.0
Percentage of ComprehensiveIncomeNetOfTax100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-6.4-6.5

Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest

us-gaap:ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest

us-gaap:ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest


Comprehensive
Period End2021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value-138.7-47.69999999999999-57.1-26.2-1.3-16.6-20.0-19.7-34.3-75.1-20.2220.156217.3-14.427-172.178-57.449-8.691-15.34-53.864-59.736-14.53573235020-20.00537-9.024-23.4399.148-27.208-10.849-10.512-3.645-87.794-6.2677.08513
Percentage of ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-31.2-12.3-14.5-6.5-0.3-3.8-4.6-4.2-7.0-15.4-4.24.70.012.95.41.9-3.9-50.7-17.2-2.7-4.8-14.0-13.1-2.812.64.310.04.4-4.89.3-2.3-7.12.8-8.6-3.6-3.2-1.1-27.6-1.81.94.2

us-gaap:ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

srt:GuarantorSubsidiaries, srt:ReportableLegalEntities


Comprehensive
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value-24.8-26.6-12.9-2.6-6.0-4.64.40.9-81.8-9.2239.62519
Percentage of ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest52.046.649.2200.036.123.0-22.3-2.6108.945.5105.59600.045.588.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-6.4-6.8-3.2-0.6-1.4-1.10.90.2-16.8-1.94.92.15.94.8
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax srt:GuarantorSubsidiaries srt:ReportableLegalEntities0.0-11.0-5.2-0.90.0-1.71.40.30.0-3.28.33.60.08.0

srt:NonGuarantorSubsidiaries, srt:ReportableLegalEntities


Comprehensive
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value-14.1-7.1-0.6-25.7-17.3-14.2-20.3-20.6-21.5-3.73.7-3.61114
Percentage of ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest29.612.42.31976.9104.271.0103.060.128.618.316.8-3600.020.564.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-3.6-1.8-0.1-6.1-4.0-3.2-4.3-4.2-4.4-0.80.8-0.82.73.5
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax srt:NonGuarantorSubsidiaries srt:ReportableLegalEntities0.0-4.7-0.4-17.50.0-8.8-12.4-12.50.0-1.91.9-1.90.08.7

srt:ParentCompany, srt:ReportableLegalEntities


Comprehensive
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value-47.69999999999999-57.1-26.2-1.4-16.6-20.0-19.7-34.3-75.1-20.2220.15621
Percentage of ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest100.0100.0100.0107.7100.0100.0100.0100.0100.0100.0100.0100.0100.199.9
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-12.3-14.5-6.5-0.3-3.8-4.6-4.2-7.0-15.4-4.24.70.012.95.4
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax srt:ParentCompany srt:ReportableLegalEntities0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest us-gaap:ConsolidationItems

srt:ConsolidationEliminations


Comprehensive
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value383313282318151910312-26.9-6.0-37.0-33.2
Percentage of ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest-81.6-59.0-51.5-2184.6-140.4-94.0-80.7-57.4-137.5-63.9-122.3-6000.0-66.0-152.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax10.08.63.46.75.44.33.44.021.22.7-5.7-1.3-8.5-8.3
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax srt:ConsolidationEliminations0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Cost Of Goods And Services Sold

us-gaap:CostOfGoodsAndServicesSold

us-gaap:CostOfGoodsAndServicesSold


Cost
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value507464390420414416428451477502546493436440383359
Percentage of CostOfGoodsAndServicesSold100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax96.0104.7100.3106.9103.298.998.4103.1100.9102.6112.2102.492.896.888.389.7

us-gaap:CostOfGoodsAndServicesSold us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

srt:GuarantorSubsidiaries, srt:ReportableLegalEntities


Cost
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value251273266281260288306327348301258261230220
Percentage of CostOfGoodsAndServicesSold64.565.164.267.560.963.864.165.163.761.159.259.460.161.4
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax64.769.666.366.759.965.864.766.871.562.655.057.553.155.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax srt:GuarantorSubsidiaries srt:ReportableLegalEntities0.0112.9107.5102.50.0104.098.8100.60.0105.292.597.40.092.1

srt:NonGuarantorSubsidiaries, srt:ReportableLegalEntities


Cost
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value138146148135167163171175198192177178152138
Percentage of CostOfGoodsAndServicesSold35.534.935.832.539.136.235.934.936.338.940.840.639.938.6
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax35.637.337.032.138.537.336.235.840.739.937.839.335.234.6
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax srt:NonGuarantorSubsidiaries srt:ReportableLegalEntities0.097.396.492.10.0101.6104.7106.60.098.493.396.00.086.0

us-gaap:CostOfGoodsAndServicesSold us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:StatementEquityComponents

us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:AccumulatedDefinedBenefitPlansAdjustment


Cost
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value0.70.8-7.00.80.41.1-4.90.80.30.6-1.10.52.70.72.31.0
Percentage of CostOfGoodsAndServicesSold0.10.2-1.80.20.10.3-1.10.20.10.1-0.20.10.60.20.60.3
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.10.2-1.80.20.10.3-1.10.20.10.1-0.20.10.60.20.50.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome us-gaap:AccumulatedDefinedBenefitPlansAdjustment0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:AccumulatedGainLossNetCashFlowHedgeParent


Cost
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value-0.1-0.0-0.1-0.1-0.00.0-0.10.00.00.0-0.10.00.00.0
Percentage of CostOfGoodsAndServicesSold-0.0-0.0-0.0-0.0-0.00.0-0.00.00.00.0-0.00.00.00.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-0.0-0.0-0.0-0.0-0.00.0-0.00.00.00.0-0.00.00.00.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome us-gaap:AccumulatedGainLossNetCashFlowHedgeParent0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Gains Losses On Extinguishment Of Debt

us-gaap:GainsLossesOnExtinguishmentOfDebt

us-gaap:GainsLossesOnExtinguishmentOfDebt


Gains
Period End2021-06-302020-12-312020-09-302014-12-312014-09-302014-06-302013-12-312013-09-302013-06-302012-12-312012-09-302012-06-302011-12-312011-09-302010-12-312010-09-30
Value-24.70.0-1.20.00.00.00.00.0-3.2720.00.00.0-0.7630.00.00.0
Percentage of GainsLossesOnExtinguishmentOfDebt100.00.0100.00.00.00.00.00.0100.00.00.00.0100.00.00.00.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-4.70.0-0.30.00.00.00.00.0-1.00.00.00.0-0.20.00.00.0

us-gaap:GainsLossesOnExtinguishmentOfDebt us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

srt:ParentCompany, srt:ReportableLegalEntities


Gains
Period End2020-12-312020-09-30
Value0.0-1.2
Percentage of GainsLossesOnExtinguishmentOfDebt0.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.0-0.3
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax srt:ParentCompany srt:ReportableLegalEntities0.00.0

us-gaap:GainsLossesOnExtinguishmentOfDebt us-gaap:DebtInstrument, us-gaap:LongtermDebtType

cenx:SeniorSecuredNotesDueJune012021, us-gaap:LongTermDebt


Gains
Period End2020-12-312020-09-30
Value0.01.2
Percentage of GainsLossesOnExtinguishmentOfDebt0.0-100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.00.3
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax cenx:SeniorSecuredNotesDueJune012021 us-gaap:LongTermDebt0.00.0

us-gaap:GainsLossesOnExtinguishmentOfDebt us-gaap:LongtermDebtType

us-gaap:SeniorNotes


Gains
Period End2021-04-30
Value24
Percentage of GainsLossesOnExtinguishmentOfDebt0.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:SeniorNotes0.0

Gross Profit

us-gaap:GrossProfit

us-gaap:GrossProfit


Gross
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value20-20.7-1.2-27.1-13.04.86.7-13.7-4.1-12.8-59.3-11.83314474122165.057-17.6125.582-3.052-18.701-42.4238.34294897538-1.7581512-5.69817163.255.95720-13.63211494241152133
Percentage of GrossProfit100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax4.0-4.7-0.3-6.9-3.21.11.5-3.1-0.9-2.6-12.2-2.47.23.211.010.35.84.61.5-5.31.7-1.0-4.9-9.31.616.016.315.18.4-0.43.83.1-1.75.55.21.11.86.3-4.33.313.513.013.05.67.511.9

us-gaap:GrossProfit us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

srt:GuarantorSubsidiaries, srt:ReportableLegalEntities


Gross
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value-8.4-31.2-18.6-6.86.8-11.23.6-2.0-43.7-14.9207.02418
Percentage of GrossProfit700.0115.1143.1-141.7101.581.8-87.815.673.7126.362.048.351.645.6
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-2.2-7.9-4.6-1.61.6-2.60.8-0.4-9.0-3.14.41.55.74.7
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax srt:GuarantorSubsidiaries srt:ReportableLegalEntities0.0-12.9-7.5-2.50.0-4.01.2-0.60.0-5.27.52.60.07.9

srt:NonGuarantorSubsidiaries, srt:ReportableLegalEntities


Gross
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value7.24.15.611-0.1-2.5-7.7-10.8-15.63.1127.52522
Percentage of GrossProfit-600.0-15.1-43.1241.7-1.518.2187.884.426.3-26.338.051.754.154.3
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax1.91.01.42.8-0.0-0.6-1.6-2.2-3.20.62.71.76.05.6
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax srt:NonGuarantorSubsidiaries srt:ReportableLegalEntities0.02.73.67.90.0-1.6-4.7-6.60.01.66.74.00.014.0

Income Tax Expense Benefit

us-gaap:IncomeTaxExpenseBenefit

us-gaap:IncomeTaxExpenseBenefit


Income
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value-48.3-2.3-1.50.30.9-2.8-2.7-1.3-1.6-2.9-3.21.72.3-1.03.1183.3211.452-0.3086.061-0.848-0.319-2.07-2.929-2.1615.0659.301116.4441.654-1.094-1.5831.3842.7912.5171.5261.1683.3952.8212.2135.3873.6363.1232.803-0.574.6194.281
Percentage of IncomeTaxExpenseBenefit100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-9.1-0.5-0.40.10.2-0.7-0.6-0.3-0.3-0.6-0.70.40.5-0.20.70.80.4-0.11.8-0.3-0.1-0.6-0.8-0.51.01.62.11.30.4-0.3-0.40.30.80.80.50.41.00.90.71.61.01.00.9-0.21.61.5

us-gaap:IncomeTaxExpenseBenefit us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

srt:NonGuarantorSubsidiaries, srt:ReportableLegalEntities


Income
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value-1.30.31.4-2.3-1.7-0.6-1.7-1.9-1.32.22.6-1.13.43.3
Percentage of IncomeTaxExpenseBenefit86.7100.0155.682.163.046.2106.265.540.6129.4113.0110.0109.099.4
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-0.30.10.3-0.5-0.4-0.1-0.4-0.4-0.30.50.6-0.20.80.8
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax srt:NonGuarantorSubsidiaries srt:ReportableLegalEntities0.00.20.9-1.60.0-0.4-1.0-1.20.01.11.4-0.60.02.0

srt:ParentCompany, srt:ReportableLegalEntities


Income
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value-0.2-0.0-0.5-0.50.4-0.70.1-1.0-1.9-0.5-0.30.10.60.0
Percentage of IncomeTaxExpenseBenefit13.3-0.0-55.617.9-14.853.8-6.234.559.4-29.4-13.0-10.019.20.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-0.1-0.0-0.1-0.10.1-0.20.0-0.2-0.4-0.1-0.10.00.10.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax srt:ParentCompany srt:ReportableLegalEntities0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:IncomeTaxExpenseBenefit us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:StatementEquityComponents

us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:AccumulatedDefinedBenefitPlansAdjustment


Income
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
Value-0.1-0.11.9-0.2-0.3-0.31.9-0.3-0.3-0.32.7-0.4-0.4-0.42.737-0.391-0.3011.0830.3350.390.3910.391-0.396-0.392-0.39-0.3910.0-0.548-0.559-0.7032.651-0.374-0.374-0.374
Percentage of IncomeTaxExpenseBenefit0.24.3-126.7-66.7-33.310.7-70.423.118.810.3-84.4-23.5-17.440.087.8-11.8-20.7-351.65.5-46.0-122.6-18.913.518.1-7.7-4.20.0-8.5-33.864.3-167.5-27.0-13.4-14.9
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-0.0-0.00.5-0.1-0.1-0.10.4-0.1-0.1-0.10.6-0.1-0.1-0.10.6-0.1-0.10.30.10.10.10.1-0.1-0.1-0.1-0.10.0-0.1-0.1-0.20.7-0.1-0.1-0.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome us-gaap:AccumulatedDefinedBenefitPlansAdjustment0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:AccumulatedGainLossNetCashFlowHedgeParent


Income
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value0.00.0-0.10.00.00.0-0.10.00.00.00.00.00.00.0
Percentage of IncomeTaxExpenseBenefit-0.0-0.06.70.00.0-0.03.7-0.0-0.0-0.0-0.00.00.0-0.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.00.0-0.00.00.00.0-0.00.00.00.00.00.00.00.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome us-gaap:AccumulatedGainLossNetCashFlowHedgeParent0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Income Taxes Paid

us-gaap:IncomeTaxesPaid

us-gaap:IncomeTaxesPaid


Income
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value0.10.00.10.00.20.00.20.18.51.03.10.52.0941.671-1.2533.0493.6593.9293.722.596101.34111.1422.113.4394.7941.8461.4133.531107.83165.5461122140.44627
Percentage of IncomeTaxesPaid100.00.0100.00.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.00.00.00.00.00.00.00.01.70.20.70.10.50.4-0.30.81.11.21.10.82.70.32.20.20.40.71.00.40.33.31.13.32.55.51.73.57.24.10.18.3

Interest Expense Debt

us-gaap:InterestExpenseDebt

us-gaap:InterestExpenseDebt


Interest
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value7.59.08.79.15.96.05.75.65.85.8
Percentage of InterestExpenseDebt100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax1.42.02.22.31.51.41.31.31.21.2

us-gaap:InterestExpenseDebt us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

srt:GuarantorSubsidiaries, srt:ReportableLegalEntities


Interest
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value0.30.40.40.40.50.40.40.4
Percentage of InterestExpenseDebt3.44.46.86.78.87.16.96.9
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.10.10.10.10.10.10.10.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax srt:GuarantorSubsidiaries srt:ReportableLegalEntities0.00.20.20.10.00.10.10.1

srt:NonGuarantorSubsidiaries, srt:ReportableLegalEntities


Interest
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value0.40.40.10.50.10.10.10.0
Percentage of InterestExpenseDebt4.64.41.78.31.81.81.70.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.10.10.00.10.00.00.00.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax srt:NonGuarantorSubsidiaries srt:ReportableLegalEntities0.00.30.10.30.00.10.10.0

srt:ParentCompany, srt:ReportableLegalEntities


Interest
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value8.08.35.45.15.15.15.35.4
Percentage of InterestExpenseDebt92.091.291.585.089.591.191.493.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax2.12.11.31.21.21.21.11.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax srt:ParentCompany srt:ReportableLegalEntities0.00.00.00.00.00.00.00.0

Interest Paid Net

us-gaap:InterestPaidNet

us-gaap:InterestPaidNet


Interest
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value9.599999999999998160.43.1100.8101.0100.49.80.09.70.29.5
Percentage of InterestPaidNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax1.83.60.10.82.50.22.30.22.20.12.00.02.10.02.2

Net Income Loss

us-gaap:NetIncomeLoss

us-gaap:NetIncomeLoss


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value-35.1-140.0-35.5-58.2-26.9-2.7-4.8-20.7-20.7-34.6-65.0-20.319-0.335207.131-15.139-168.464-58.273-9.515-16.163-43.08-56.112-33.89773615020-20.104-9.675-9.507-34.5738.253-6.909-12.023-12.277-4.401-31.107-6.6232565-16.7875.1466.332
Percentage of NetIncomeLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-6.6-31.5-9.1-14.8-6.7-0.6-1.1-4.7-4.4-7.1-13.3-4.24.1-0.18.35.21.8-4.1-49.6-17.5-2.9-5.1-11.2-12.3-6.512.511.210.14.4-4.8-2.4-2.4-10.42.6-2.2-3.9-3.8-1.3-9.8-1.96.57.720.6-6.01.82.2

us-gaap:NetIncomeLoss us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

srt:GuarantorSubsidiaries, srt:ReportableLegalEntities


Net
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value-17.8-27.4-13.3-3.7-1.2-5.44.10.3-53.7-9.7208.91318
Percentage of NetIncomeLoss50.147.149.4137.025.026.1-19.8-0.982.647.8105.2-2966.738.087.6
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-4.6-7.0-3.3-0.9-0.3-1.20.90.1-11.0-2.04.32.03.14.5
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax srt:GuarantorSubsidiaries srt:ReportableLegalEntities0.0-11.3-5.4-1.30.0-1.91.30.10.0-3.47.33.30.07.6

srt:NonGuarantorSubsidiaries, srt:ReportableLegalEntities


Net
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value-11.5-7.5-1.1-26.1-14.1-14.7-21.5-20.9-25.5-4.13.4-4.01113
Percentage of NetIncomeLoss32.412.94.1966.7293.871.0103.960.439.220.217.51333.331.365.9
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-3.0-1.9-0.3-6.2-3.2-3.4-4.5-4.3-5.2-0.90.7-0.92.63.4
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax srt:NonGuarantorSubsidiaries srt:ReportableLegalEntities0.0-5.0-0.7-17.80.0-9.1-13.1-12.70.0-2.11.8-2.10.08.5

srt:ParentCompany, srt:ReportableLegalEntities


Net
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value-35.5-58.2-26.9-2.8-4.8-20.7-20.7-34.6-65.0-20.319-0.33520
Percentage of NetIncomeLoss100.0100.0100.0103.7100.0100.0100.0100.0100.0100.0100.0100.0100.0100.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-9.1-14.8-6.7-0.7-1.1-4.7-4.4-7.1-13.3-4.24.1-0.18.35.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax srt:ParentCompany srt:ReportableLegalEntities0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:NetIncomeLoss us-gaap:ConsolidationItems

srt:ConsolidationEliminations


Net
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value29341429152017207913-23.8-4.9-24.8-31.9
Percentage of NetIncomeLoss-82.5-60.0-53.5-1107.4-318.8-97.1-84.1-59.5-121.8-68.0-122.71633.3-69.3-153.5
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax7.58.93.67.13.54.63.74.216.32.9-5.1-1.1-5.7-8.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax srt:ConsolidationEliminations0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:NetIncomeLoss us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:StatementEquityComponents

us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:AccumulatedDefinedBenefitPlansAdjustment


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
Value-1.2-1.3-5.5-1.2-0.8-1.4-7.6-0.7-1.0-0.3-2.70.12.6-0.44.137-1.0840.2060.751.4220.8620.8620.861-4.130.5291.3580.1175.455-0.098-0.5170.1550.3970.5380.840.95
Percentage of NetIncomeLoss3.40.915.52.13.051.9158.33.44.80.94.2-0.513.4133.311.6-5.22.9-5.0-0.8-1.5-9.1-5.39.6-0.9-4.00.28.8-0.2-2.5-0.8-4.1-5.7-2.411.5
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-0.2-0.3-1.4-0.3-0.2-0.3-1.7-0.2-0.2-0.1-0.60.00.6-0.11.0-0.30.10.20.40.30.30.3-1.10.10.30.01.0-0.0-0.10.00.10.10.30.3
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome us-gaap:AccumulatedDefinedBenefitPlansAdjustment0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:AccumulatedGainLossNetCashFlowHedgeParent


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value0.1-0.0-0.20.10.00.0-0.20.00.00.0-0.30.00.00.0
Percentage of NetIncomeLoss-0.30.00.6-0.2-0.0-0.04.2-0.0-0.0-0.00.5-0.00.0-0.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.0-0.0-0.10.00.00.0-0.00.00.00.0-0.10.00.00.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome us-gaap:AccumulatedGainLossNetCashFlowHedgeParent0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:NetIncomeLoss us-gaap:StatementEquityComponents

us-gaap:RetainedEarnings


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value-35.1-140.0-35.5-58.2-26.9-2.7-4.8-20.7-20.7-34.6-20.319-0.3
Percentage of NetIncomeLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-6.6-31.5-9.1-14.8-6.7-0.6-1.1-4.7-4.4-7.1-4.24.1-0.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:RetainedEarnings0.00.00.00.00.00.00.00.00.00.00.00.00.0

Net Income Loss Available To Common Stockholders Basic

us-gaap:NetIncomeLossAvailableToCommonStockholdersBasic

us-gaap:NetIncomeLossAvailableToCommonStockholdersBasic


Net
Period End2021-06-302020-06-302019-06-302018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-06-302011-03-312010-06-302010-03-31
Value-35.1-26.9-20.7-65.0-20.317-0.332196.563-15.139-168.464-58.273-9.515-16.163-43.08-56.112-33.89767564618-20.104-9.675-9.507-34.5737.567-6.909-12.023-12.277-4.40122234.7235.808
Percentage of NetIncomeLossAvailableToCommonStockholdersBasic100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-6.6-6.7-4.4-13.3-4.23.8-0.17.64.81.7-4.1-49.6-17.5-2.9-5.1-11.2-12.3-6.511.510.39.24.1-4.8-2.4-2.4-10.42.4-2.2-3.9-3.8-1.36.07.01.62.0

Net Income Loss Available To Common Stockholders Diluted

us-gaap:NetIncomeLossAvailableToCommonStockholdersDiluted

us-gaap:NetIncomeLossAvailableToCommonStockholdersDiluted


Net
Period End2021-06-302020-06-302019-06-302018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value-35.1-26.9-20.7-20.317-0.3196.563-15.1-58.273-9.515-16.163-56.112-33.897674618-20.104-9.507-34.5737.567-12.023-12.277-4.401-28.599-6.62223
Percentage of NetIncomeLossAvailableToCommonStockholdersDiluted100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-6.6-6.7-4.4-4.23.8-0.14.81.7-4.1-17.5-2.9-5.1-12.3-6.511.59.24.1-4.8-2.4-10.42.4-3.9-3.8-1.3-9.0-1.96.07.0

Operating Income Loss

us-gaap:OperatingIncomeLoss

us-gaap:OperatingIncomeLoss


Operating
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value12-36.9-13.2-37.9-25.0-4.4-2.9-25.2-16.3-27.8-68.4-15.6213.54332125.176-159.644-55.053-4.941-13.558-28.486-55.526-35.12180666226-14.234-8.631-4.242-23.870.1872.645-13.32-5.0118.412-27.1720.7153637790.1875.90817
Percentage of OperatingIncomeLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax2.3-8.3-3.4-9.6-6.2-1.0-0.7-5.8-3.4-5.7-14.0-3.24.60.810.08.13.31.4-47.0-16.5-1.5-4.3-7.4-12.2-6.713.612.112.45.7-3.4-2.2-1.1-7.20.10.8-4.4-1.52.6-8.50.29.911.525.10.12.16.0

us-gaap:OperatingIncomeLoss us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

srt:GuarantorSubsidiaries, srt:ReportableLegalEntities


Operating
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value-20.3-31.2-18.6-6.8-9.5-11.23.6-2.0-55.3-14.9207.01118
Percentage of OperatingIncomeLoss153.882.374.4154.5327.644.4-22.17.280.895.597.2200.027.358.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-5.2-7.9-4.6-1.6-2.2-2.60.8-0.4-11.4-3.14.41.52.74.7
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax srt:GuarantorSubsidiaries srt:ReportableLegalEntities0.0-12.9-7.5-2.50.0-4.01.2-0.60.0-5.27.52.60.07.9

srt:NonGuarantorSubsidiaries, srt:ReportableLegalEntities


Operating
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value3.83.95.110-4.4-2.7-8.4-11.7-19.67.7126.52927
Percentage of OperatingIncomeLoss-28.8-10.3-20.4-245.5151.710.751.542.128.7-49.455.8185.767.584.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax1.01.01.32.6-1.0-0.6-1.8-2.4-4.01.62.61.46.76.8
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax srt:NonGuarantorSubsidiaries srt:ReportableLegalEntities0.02.63.37.30.0-1.7-5.1-7.10.03.96.33.50.017.0

srt:ParentCompany, srt:ReportableLegalEntities


Operating
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value3.3-10.6-11.5-8.411-11.3-11.5-14.16.5-8.4-11.4-10.05.6-13.7
Percentage of OperatingIncomeLoss-25.028.046.0190.9-379.344.870.650.7-9.553.8-53.0-285.712.9-42.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.8-2.7-2.9-2.02.5-2.6-2.4-2.91.3-1.7-2.4-2.21.3-3.4
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax srt:ParentCompany srt:ReportableLegalEntities0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Other Comprehensive Income Loss Net Of Tax

us-gaap:OtherComprehensiveIncomeLossNetOfTax

us-gaap:OtherComprehensiveIncomeLossNetOfTax


Other
Period End2021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-30
Value1.3-12.21.10.71.4-11.80.71.00.3-10.10.12.60.4201.0470.1690.712-3.7140.8240.8240.823-10.784-3.624190.078-38.316-0.153-0.1310.099460.483110.895-20.2991.1741.7650.756-56.6870.333
Percentage of OtherComprehensiveIncomeLossNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.3-3.10.30.20.3-2.70.20.20.1-2.10.00.60.14.70.30.00.2-1.10.20.30.3-2.8-0.83.70.0-7.0-0.0-0.00.011.70.13.40.3-6.40.40.50.2-17.80.1

us-gaap:OtherComprehensiveIncomeLossNetOfTax us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

srt:GuarantorSubsidiaries, srt:ReportableLegalEntities


Other
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value-7.00.80.41.1-4.80.80.30.6-28.10.52.80.7111.0
Percentage of OtherComprehensiveIncomeLossNetOfTax57.472.757.178.640.7114.330.0200.0278.2500.0107.7175.058.895.5
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-1.80.20.10.3-1.10.20.10.1-5.80.10.60.22.70.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax srt:GuarantorSubsidiaries srt:ReportableLegalEntities0.00.30.20.40.00.30.10.20.00.21.00.30.00.4

srt:NonGuarantorSubsidiaries, srt:ReportableLegalEntities


Other
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value-2.60.40.50.4-3.20.51.20.34.00.40.30.40.30.3
Percentage of OtherComprehensiveIncomeLossNetOfTax21.336.471.428.627.171.4120.0100.0-39.6400.011.5100.01.528.7
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-0.70.10.10.1-0.70.10.30.10.80.10.10.10.10.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax srt:NonGuarantorSubsidiaries srt:ReportableLegalEntities0.00.30.30.30.00.30.70.20.00.20.20.20.00.2

srt:ParentCompany, srt:ReportableLegalEntities


Other
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value-12.21.10.71.4-11.80.71.00.3-10.10.12.60.4201.0
Percentage of OtherComprehensiveIncomeLossNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.495.5
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-3.10.30.20.3-2.70.20.20.1-2.10.00.60.14.70.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax srt:ParentCompany srt:ReportableLegalEntities0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:OtherComprehensiveIncomeLossNetOfTax us-gaap:ConsolidationItems

srt:ConsolidationEliminations


Other
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value9.6-1.2-0.9-1.58.0-1.3-1.5-0.924-0.9-3.1-1.1-12.2-1.3
Percentage of OtherComprehensiveIncomeLossNetOfTax-78.7-109.1-128.6-107.1-67.8-185.7-150.0-300.0-238.6-900.0-119.2-275.0-60.3-124.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax2.5-0.3-0.2-0.41.8-0.3-0.3-0.24.9-0.2-0.7-0.2-2.8-0.3
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax srt:ConsolidationEliminations0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:OtherComprehensiveIncomeLossNetOfTax us-gaap:StatementEquityComponents

us-gaap:AccumulatedOtherComprehensiveIncome


Other
Period End2021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value1.3-12.21.10.71.4-11.80.71.00.3-10.10.12.60.4
Percentage of OtherComprehensiveIncomeLossNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.3-3.10.30.20.3-2.70.20.20.1-2.10.00.60.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:AccumulatedOtherComprehensiveIncome0.00.00.00.00.00.00.00.00.00.00.00.00.0

Other Nonoperating Income Expense

us-gaap:OtherNonoperatingIncomeExpense

us-gaap:OtherNonoperatingIncomeExpense


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-06-302012-03-312011-06-302011-03-31
Value1.21.90.50.01.31.70.5-0.9-1.71.11.20.72.1-1.1-0.0960.427-1.8760.3841.781-0.157-0.299-0.006-1.6170.1140.0931.0541.414-0.470.3-0.2531.4970.213-1.2840.070.1610.306-1.1320.677
Percentage of OtherNonoperatingIncomeExpense100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.20.40.10.00.30.40.1-0.2-0.40.20.20.10.4-0.2-0.00.1-0.50.10.5-0.0-0.1-0.0-0.40.00.00.20.3-0.10.1-0.10.40.1-0.40.00.00.1-0.30.2

us-gaap:OtherNonoperatingIncomeExpense us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

srt:GuarantorSubsidiaries, srt:ReportableLegalEntities


Other
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value0.10.20.8-0.1-0.8-0.1-1.3-0.5-1.70.0-0.10.00.20.0
Percentage of OtherNonoperatingIncomeExpense20.00.061.5-5.9-160.011.176.5-45.5-141.70.0-4.8-0.0-208.30.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.00.10.2-0.0-0.2-0.0-0.3-0.1-0.30.0-0.00.00.00.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax srt:GuarantorSubsidiaries srt:ReportableLegalEntities0.00.10.3-0.00.0-0.0-0.4-0.20.00.0-0.00.00.00.0

srt:NonGuarantorSubsidiaries, srt:ReportableLegalEntities


Other
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value0.5-0.10.71.50.9-0.9-0.40.81.40.72.2-1.6-3.20.4
Percentage of OtherNonoperatingIncomeExpense100.00.053.888.2180.0100.023.572.7116.7100.0104.8145.53333.393.7
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.1-0.00.20.40.2-0.2-0.10.20.30.10.5-0.4-0.70.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax srt:NonGuarantorSubsidiaries srt:ReportableLegalEntities0.0-0.10.51.00.0-0.6-0.20.50.00.41.2-0.90.00.2

srt:ParentCompany, srt:ReportableLegalEntities


Other
Period End2020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value-0.1-0.20.30.40.10.00.81.50.00.00.5-0.50.0
Percentage of OtherNonoperatingIncomeExpense0.0-15.417.680.0-11.1-0.072.7125.00.00.0-45.5520.80.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-0.0-0.00.10.10.00.00.20.30.00.00.1-0.10.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax srt:ParentCompany srt:ReportableLegalEntities0.00.00.00.00.00.00.00.00.00.00.00.00.0

Revenue From Contract With Customer Excluding Assessed Tax

us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax

us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value528444389392401421435438473490486481470454433400388365339333326318383454523587551500458420401399331321317304323326318345366326316279287285
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

srt:GuarantorSubsidiaries, srt:ReportableLegalEntities


Revenue
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value243242247274267277309325304286279268255239
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax62.661.661.665.161.563.365.466.462.559.559.459.058.859.8
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax62.661.661.665.161.563.365.466.462.559.559.459.058.859.8
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax srt:GuarantorSubsidiaries srt:ReportableLegalEntities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

srt:NonGuarantorSubsidiaries, srt:ReportableLegalEntities


Revenue
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value145150154147167160163164182195190186178161
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax37.438.438.434.938.536.734.633.637.540.540.641.041.240.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax37.438.438.434.938.536.734.633.637.540.540.641.041.240.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax srt:NonGuarantorSubsidiaries srt:ReportableLegalEntities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:StatementGeographical

country:IS


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value180167145150154147167160163164182195190186
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax34.137.837.438.438.334.938.536.734.633.637.540.540.641.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax34.137.837.438.438.334.938.536.734.633.637.540.540.641.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax country:IS100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

country:US


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value347276243242247274267277309325304286279268
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax65.962.262.661.661.765.161.563.365.466.462.559.559.459.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax65.962.262.661.661.765.161.563.365.466.462.559.559.459.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax country:US100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Revenues

us-gaap:Revenues

us-gaap:Revenues


Revenues
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value528444389392401421435438473490486481470454433400388365339333326318383454523587551500458420401399331321317304323326318345366326316279287285
Percentage of Revenues100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Selling General And Administrative Expense

us-gaap:SellingGeneralAndAdministrativeExpense

us-gaap:SellingGeneralAndAdministrativeExpense


Selling
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value8.7161111118.99.21111148.78.8121011139.35210109.7339.9459.6258.5661110111612101021141516109.1827.1518.4598.9167.95181011121012
Percentage of SellingGeneralAndAdministrativeExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax1.63.63.02.82.92.12.12.62.53.01.81.82.62.42.63.52.42.93.22.93.03.02.22.51.92.03.02.42.32.45.43.64.65.13.33.02.22.62.82.35.13.33.54.53.84.3

us-gaap:SellingGeneralAndAdministrativeExpense us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

srt:NonGuarantorSubsidiaries, srt:ReportableLegalEntities


Selling
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value3.20.40.30.53.90.30.40.63.60.40.60.73.50.3
Percentage of SellingGeneralAndAdministrativeExpense27.13.62.55.642.42.63.44.141.44.55.06.530.72.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.80.10.10.10.90.10.10.10.70.10.10.20.80.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax srt:NonGuarantorSubsidiaries srt:ReportableLegalEntities2.20.30.20.32.30.20.20.42.00.20.30.42.00.2

srt:ParentCompany, srt:ReportableLegalEntities


Selling
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value-3.310118.4-11.0111114-6.58.41110.0-5.613
Percentage of SellingGeneralAndAdministrativeExpense-28.096.497.594.4-119.697.496.695.9-74.795.595.093.5-49.197.9
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-0.82.72.92.0-2.52.62.42.9-1.31.72.42.2-1.33.4
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax srt:ParentCompany srt:ReportableLegalEntities0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:SellingGeneralAndAdministrativeExpense us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:StatementEquityComponents

us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:AccumulatedDefinedBenefitPlansAdjustment


Selling
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
Value0.20.2-2.50.10.20.2-3.5-0.3-0.2-0.4-1.0-0.4-0.1-0.4-1.5150.1090.8450.1320.090.1250.1250.125-0.520.2520.1360.1830.1420.1420.0170.2680.2980.1480.3040.24
Percentage of SellingGeneralAndAdministrativeExpense2.31.2-21.20.91.72.2-38.0-2.6-1.7-2.7-11.5-4.5-0.8-3.7-13.30.89.01.20.81.31.31.3-6.12.21.41.50.91.20.22.71.41.02.01.5
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.00.0-0.60.00.00.0-0.8-0.1-0.0-0.1-0.2-0.1-0.0-0.1-0.30.00.20.00.00.00.00.0-0.10.10.00.00.00.00.00.10.10.00.10.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome us-gaap:AccumulatedDefinedBenefitPlansAdjustment0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Assets

us-gaap:Assets

us-gaap:Assets


Assets
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value14051363139914051524159114991491151515301537161316161580158115631525152515401688171917231752190619892083201418391776178618101859185117911776178317791797181118631899192119231861
Percentage of Assets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:Assets us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

srt:GuarantorSubsidiaries, srt:ReportableLegalEntities


Assetsus-gaap:
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-12-31
Value1224120712061219122512101351128412041201993
Percentage of Assets87.585.979.276.781.781.189.283.978.474.562.8
Percentage of Assets87.585.979.276.781.781.189.283.978.474.562.8
Percentage of Assets srt:GuarantorSubsidiaries srt:ReportableLegalEntities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

srt:NonGuarantorSubsidiaries, srt:ReportableLegalEntities


Assetsus-gaap:
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-12-31
Value785778787813808796822833854889918
Percentage of Assets56.155.451.751.153.953.454.354.455.655.158.0
Percentage of Assets56.155.451.751.153.953.454.354.455.655.158.0
Percentage of Assets srt:NonGuarantorSubsidiaries srt:ReportableLegalEntities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

srt:ParentCompany, srt:ReportableLegalEntities


Assetsus-gaap:
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-12-31
Value13411374150015081430144016061544147715031380
Percentage of Assets95.997.898.494.895.496.6106.0100.996.193.287.3
Percentage of Assets95.997.898.494.895.496.6106.0100.996.193.287.3
Percentage of Assets srt:ParentCompany srt:ReportableLegalEntities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:Assets us-gaap:ConsolidationItems

srt:ConsolidationEliminations


Assetsus-gaap:
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-12-31
Value-1952.2-1955.0-1970.6-1951.0-1964.2-1955.5-2265.0-2131.2-1999.3-1980.1-1710.1
Percentage of Assets-139.5-139.1-129.3-122.6-131.0-131.1-149.5-139.3-130.0-122.7-108.1
Percentage of Assets-139.5-139.1-129.3-122.6-131.0-131.1-149.5-139.3-130.0-122.7-108.1
Percentage of Assets srt:ConsolidationEliminations100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Liabilities And Stockholders Equity

us-gaap:LiabilitiesAndStockholdersEquity

us-gaap:LiabilitiesAndStockholdersEquity


Liabilities
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
Value1405136313991405152415911499149115151530153716131616158015811563152515251540168817191723175219061989208320141839177617861810185918511791177617831779179718111863189919211923
Percentage of LiabilitiesAndStockholdersEquity100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:LiabilitiesAndStockholdersEquity us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

srt:GuarantorSubsidiaries, srt:ReportableLegalEntities


Liabilities
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-12-31
Value1224120712061219122512101351128412041201993
Percentage of LiabilitiesAndStockholdersEquity87.585.979.276.781.781.189.283.978.474.562.8
Percentage of Assets87.585.979.276.781.781.189.283.978.474.562.8
Percentage of Assets srt:GuarantorSubsidiaries srt:ReportableLegalEntities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

srt:NonGuarantorSubsidiaries, srt:ReportableLegalEntities


Liabilities
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-12-31
Value785778787813808796822833854889918
Percentage of LiabilitiesAndStockholdersEquity56.155.451.751.153.953.454.354.455.655.158.0
Percentage of Assets56.155.451.751.153.953.454.354.455.655.158.0
Percentage of Assets srt:NonGuarantorSubsidiaries srt:ReportableLegalEntities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

srt:ParentCompany, srt:ReportableLegalEntities


Liabilities
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-12-31
Value13411374150015081430144016061544147715031380
Percentage of LiabilitiesAndStockholdersEquity95.997.898.494.895.496.6106.0100.996.193.287.3
Percentage of Assets95.997.898.494.895.496.6106.0100.996.193.287.3
Percentage of Assets srt:ParentCompany srt:ReportableLegalEntities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:LiabilitiesAndStockholdersEquity us-gaap:ConsolidationItems

srt:ConsolidationEliminations


Liabilities
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-12-31
Value-1952.2-1955.0-1970.6-1951.0-1964.2-1955.5-2265.0-2131.2-1999.3-1980.1-1710.1
Percentage of LiabilitiesAndStockholdersEquity-139.5-139.1-129.3-122.6-131.0-131.1-149.5-139.3-130.0-122.7-108.1
Percentage of Assets-139.5-139.1-129.3-122.6-131.0-131.1-149.5-139.3-130.0-122.7-108.1
Percentage of Assets srt:ConsolidationEliminations100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Stockholders Equity

us-gaap:StockholdersEquity

us-gaap:StockholdersEquity


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value370408546592648673675689709728762833853830829773750742756937994100210171071111611381091105410039831002965968992982100910201030103811321177116811541067
Percentage of StockholdersEquity100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets26.429.939.042.242.642.345.046.246.847.649.651.752.852.552.549.449.248.749.155.557.858.258.156.256.154.754.257.356.555.055.451.952.355.455.356.657.357.357.360.862.060.860.057.4

us-gaap:StockholdersEquity us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

srt:GuarantorSubsidiaries, srt:ReportableLegalEntities


Stockholders
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-12-31
Value586611637650650644636630629711687
Percentage of StockholdersEquity107.4103.298.396.596.393.489.786.682.685.382.9
Percentage of Assets41.943.541.940.943.343.242.041.240.944.143.5
Percentage of Assets srt:GuarantorSubsidiaries srt:ReportableLegalEntities47.950.652.953.353.153.247.149.152.259.269.2

srt:NonGuarantorSubsidiaries, srt:ReportableLegalEntities


Stockholders
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-12-31
Value-25.6-11.4-4.5-3.62238527293115118
Percentage of StockholdersEquity-4.7-1.9-0.7-0.53.35.67.410.012.313.814.2
Percentage of Assets-1.8-0.8-0.3-0.21.52.63.54.86.17.17.5
Percentage of Assets srt:NonGuarantorSubsidiaries srt:ReportableLegalEntities-3.3-1.5-0.6-0.42.74.96.48.711.012.912.9

srt:ParentCompany, srt:ReportableLegalEntities


Stockholders
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-12-31
Value546592648673675689709728762833829
Percentage of StockholdersEquity100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets39.042.242.642.345.046.246.847.649.651.752.5
Percentage of Assets srt:ParentCompany srt:ReportableLegalEntities40.743.143.244.747.247.944.247.151.655.460.1

us-gaap:StockholdersEquity us-gaap:ConsolidationItems

srt:ConsolidationEliminations


Stockholders
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-12-31
Value-560.9-599.7-633.4-646.7-672.2-682.8-689.0-702.9-722.8-826.1-805.8
Percentage of StockholdersEquity-102.7-101.2-97.6-96.0-99.6-99.0-97.1-96.5-94.8-99.1-97.1
Percentage of Assets-40.1-42.7-41.6-40.6-44.8-45.8-45.5-45.9-47.0-51.2-50.9
Percentage of Assets srt:ConsolidationEliminations28.730.732.133.134.234.930.433.036.241.747.1

us-gaap:StockholdersEquity us-gaap:StatementEquityComponents

us-gaap:AccumulatedDefinedBenefitPlansAdjustment


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-31
Value-118.1-119.3-120.6-108.3-109.5-110.3-111.7-100.0-100.7-101.7-100.7-90.7-90.8-93.4-93.88-114.141-115.225-115.431-116.181-108.082-108.944-109.806-110.667-99.92-96.335-115.735-115.852
Percentage of StockholdersEquity-31.9-29.2-22.1-18.3-16.9-16.4-16.5-14.5-14.2-14.0-13.2-10.9-10.6-11.2-11.3-14.8-15.3-15.5-15.4-11.5-11.0-10.9-10.9-9.3-8.6-10.2-10.6
Percentage of Assets-8.4-8.8-8.6-7.7-7.2-6.9-7.4-6.7-6.6-6.6-6.5-5.6-5.6-5.9-5.9-7.3-7.6-7.6-7.5-6.4-6.3-6.4-6.3-5.2-4.8-5.6-5.8
Percentage of Assets us-gaap:AccumulatedDefinedBenefitPlansAdjustment0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:AccumulatedGainLossNetCashFlowHedgeParent


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-31
Value1.71.81.81.81.91.91.92.02.02.02.02.12.12.12.12.3
Percentage of StockholdersEquity0.50.40.30.30.30.30.30.30.30.30.30.30.20.30.30.3
Percentage of Assets0.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.1
Percentage of Assets us-gaap:AccumulatedGainLossNetCashFlowHedgeParent0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:AccumulatedOtherComprehensiveIncome


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312013-12-312012-12-312011-12-312010-12-312009-12-31
Value-116.4-117.5-118.8-106.5-107.6-108.4-109.8-98.0-98.7-99.7-98.7-88.7-88.7-91.3-91.742-111.965-113.012-113.181-113.893-110.179-111.003-111.827-112.65-101.866-98.242-117.604-117.682-91.832-151.192-134.588-49.976-74.27
Percentage of StockholdersEquity-31.4-28.8-21.8-18.0-16.6-16.1-16.3-14.2-13.9-13.7-12.9-10.6-10.4-11.0-11.1-14.5-15.1-15.2-15.1-11.8-11.2-11.2-11.1-9.5-8.8-10.3-10.8-9.2-15.4-13.0-4.3-7.0
Percentage of Assets-8.3-8.6-8.5-7.6-7.1-6.8-7.3-6.6-6.5-6.5-6.4-5.5-5.5-5.8-5.8-7.2-7.4-7.4-7.4-6.5-6.5-6.5-6.4-5.3-4.9-5.6-5.8-5.1-8.5-7.4-2.6-4.0
Percentage of Assets us-gaap:AccumulatedOtherComprehensiveIncome0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:AdditionalPaidInCapital


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-312009-12-31
Value25272530253025282527252625262524252425232523251925182518251725152513251025082507250625032501
Percentage of StockholdersEquity682.2619.9463.3426.8389.6375.0374.3366.0355.8346.6331.0302.3295.3303.2303.4332.4247.0230.1250.2255.2241.4216.9234.3
Percentage of Assets179.8185.6180.8179.9165.9158.8168.5169.2166.6164.9164.1156.1155.8159.3159.2163.3143.4124.6138.6141.2138.4130.2134.4
Percentage of Assets us-gaap:AdditionalPaidInCapital0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:CommonStock


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-312009-12-31
Value1.01.01.01.01.01.01.01.01.01.01.00.90.90.90.9470.9440.9420.9390.9350.9330.9320.9280.925
Percentage of StockholdersEquity0.30.20.20.20.20.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.1
Percentage of Assets0.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.00.10.10.10.00.0
Percentage of Assets us-gaap:CommonStock0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:PreferredStock


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-312009-12-31
Value0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0010.0010.0010.0010.0010.0010.0010.0010.001
Percentage of StockholdersEquity0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0
Percentage of Assets0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0
Percentage of Assets us-gaap:PreferredStock0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:RetainedEarnings


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-312009-12-31
Value-1954.9-1919.8-1779.8-1744.2-1686.0-1659.1-1656.4-1651.6-1630.9-1610.1-1576.8-1511.9-1491.6-1511.0-1510.672-1559.252-1297.778-1252.448-1364.942-1324.629-1289.019-1300.344-1360.315
Percentage of StockholdersEquity-527.8-470.2-325.9-294.4-259.9-246.2-245.4-239.4-229.9-221.1-206.9-181.4-174.8-182.0-182.1-206.1-127.5-114.8-136.1-134.8-124.1-112.6-127.4
Percentage of Assets-139.1-140.8-127.2-124.1-110.6-104.3-110.4-110.7-107.6-105.2-102.6-93.7-92.3-95.6-95.5-101.2-74.1-62.2-75.4-74.6-71.2-67.6-73.1
Percentage of Assets us-gaap:RetainedEarnings0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:TreasuryStock


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-312009-12-31
Value-86.3-86.3-86.3-86.3-86.3-86.3-86.3-86.3-86.3-86.3-86.3-86.3-86.3-86.3-86.276-86.276-86.276-49.924-49.92449450.00.0
Percentage of StockholdersEquity-23.3-21.1-15.8-14.6-13.3-12.8-12.8-12.5-12.2-11.9-11.3-10.4-10.1-10.4-10.4-11.4-8.5-4.6-5.05.14.40.00.0
Percentage of Assets-6.1-6.3-6.2-6.1-5.7-5.4-5.8-5.8-5.7-5.6-5.6-5.3-5.3-5.5-5.5-5.6-4.9-2.5-2.82.82.50.00.0
Percentage of Assets us-gaap:TreasuryStock0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Assets Current

us-gaap:AssetsCurrent

us-gaap:AssetsCurrent


Assets
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
Value478440456443531583487474501483506590606568553510457438440432450435448543599672599522453456471512523509487465464486488526558582577
Percentage of AssetsCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets34.032.332.631.534.936.732.531.833.131.633.036.637.536.035.032.730.028.728.625.626.225.325.628.530.132.329.828.425.525.526.027.528.328.427.426.126.127.127.028.229.430.330.0

us-gaap:AssetsCurrent us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

srt:GuarantorSubsidiaries, srt:ReportableLegalEntities


Assets
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-12-31
Value242233210249284294312316309345259
Percentage of AssetsCurrent53.352.739.642.858.362.162.365.461.158.546.9
Percentage of Assets17.416.613.815.719.019.720.620.720.121.416.4
Percentage of Assets srt:GuarantorSubsidiaries srt:ReportableLegalEntities19.819.317.520.523.224.323.124.625.728.826.1

srt:NonGuarantorSubsidiaries, srt:ReportableLegalEntities


Assets
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-12-31
Value203191188204186166177157189218226
Percentage of AssetsCurrent44.643.135.535.038.435.035.432.637.536.940.8
Percentage of Assets14.513.612.412.812.511.111.710.312.413.514.3
Percentage of Assets srt:NonGuarantorSubsidiaries srt:ReportableLegalEntities25.924.524.025.123.120.921.618.922.224.524.6

srt:ParentCompany, srt:ReportableLegalEntities


Assets
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-12-31
Value9.5181321291613119.37.02667
Percentage of AssetsCurrent2.14.224.822.23.32.92.31.91.44.512.3
Percentage of Assets0.71.38.78.21.10.90.80.60.51.74.3
Percentage of Assets srt:ParentCompany srt:ReportableLegalEntities0.71.48.88.61.11.00.70.60.51.84.9

Cash And Cash Equivalents At Carrying Value

us-gaap:CashAndCashEquivalentsAtCarryingValue

us-gaap:CashAndCashEquivalentsAtCarryingValue


Cash
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312008-12-31
Value9.0268181174147382225223873124130167174130125132117129126115122167226163133615284140127195183173156182183216232293304265256213198129
Percentage of CashAndCashEquivalentsAtCarryingValue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.61.95.85.811.49.32.61.51.71.52.54.57.78.310.611.18.68.38.67.07.57.36.66.48.410.98.17.33.52.94.67.66.910.910.49.78.810.210.111.612.215.315.80.00.00.010.60.0

us-gaap:CashAndCashEquivalentsAtCarryingValue us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

srt:GuarantorSubsidiaries, srt:ReportableLegalEntities


Cash
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-12-31
Value1.20.20.20.20.10.0-0.10.10.0-0.3-0.1
Percentage of CashAndCashEquivalentsAtCarryingValue1.50.20.10.10.30.0-0.40.50.0-0.4-0.1
Percentage of Assets0.10.00.00.00.00.0-0.00.00.0-0.0-0.0
Percentage of Assets srt:GuarantorSubsidiaries srt:ReportableLegalEntities0.10.00.00.00.00.0-0.00.00.0-0.0-0.0

srt:NonGuarantorSubsidiaries, srt:ReportableLegalEntities


Cash
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-12-31
Value79787064382125223847103
Percentage of CashAndCashEquivalentsAtCarryingValue97.595.940.344.099.093.398.1100.099.765.061.6
Percentage of Assets5.75.64.64.12.61.41.71.52.53.06.5
Percentage of Assets srt:NonGuarantorSubsidiaries srt:ReportableLegalEntities10.110.08.98.04.82.63.12.74.55.411.2

srt:ParentCompany, srt:ReportableLegalEntities


Cash
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-12-31
Value0.83.1103820.31.50.6-0.10.12664
Percentage of CashAndCashEquivalentsAtCarryingValue1.03.859.655.90.86.72.3-0.50.335.438.5
Percentage of Assets0.10.26.85.20.00.10.0-0.00.01.64.1
Percentage of Assets srt:ParentCompany srt:ReportableLegalEntities0.10.26.95.50.00.10.0-0.00.01.74.7

Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents


Cash
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312015-12-31
Value10278485177149392326233974124131168175131126133116
Percentage of CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.72.06.06.111.79.42.61.61.71.52.64.67.78.310.611.28.68.38.76.6

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

srt:GuarantorSubsidiaries, srt:ReportableLegalEntities


Cash
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-312015-12-31
Value2.02.02.02.00.90.80.70.90.80.50.70.70.70.60.5-2.8
Percentage of CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents2.42.41.11.32.33.42.63.92.00.70.60.50.40.30.4-2.4
Percentage of Assets0.10.10.10.10.10.10.00.10.10.00.00.00.00.00.0-0.2
Percentage of Assets srt:GuarantorSubsidiaries srt:ReportableLegalEntities0.20.20.20.20.10.10.10.10.10.00.00.00.10.00.00.0

srt:NonGuarantorSubsidiaries, srt:ReportableLegalEntities


Cash
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-312015-12-31
Value81807264382125223847961221031039660
Percentage of CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents96.794.040.643.497.090.195.196.597.764.377.693.061.359.372.152.2
Percentage of Assets5.85.74.74.12.61.41.71.52.53.06.07.76.56.66.23.5
Percentage of Assets srt:NonGuarantorSubsidiaries srt:ReportableLegalEntities10.410.39.28.04.82.63.12.74.55.40.00.011.20.00.00.0

srt:ParentCompany, srt:ReportableLegalEntities


Cash
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-312015-12-31
Value0.83.1103820.31.50.6-0.10.126278.564703658
Percentage of CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents0.93.658.355.20.86.42.3-0.40.335.021.96.538.340.327.650.3
Percentage of Assets0.10.26.85.20.00.10.0-0.00.01.61.70.54.14.52.43.3
Percentage of Assets srt:ParentCompany srt:ReportableLegalEntities0.10.26.95.50.00.10.0-0.00.01.70.00.04.70.00.00.0

Accounts Receivable Net Current

us-gaap:AccountsReceivableNetCurrent

us-gaap:AccountsReceivableNetCurrent


Accounts
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
Value675751503552708192908291968343404236121114129.4758.6139.8073.4647650524556518452504471504752543643
Percentage of AccountsReceivableNetCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets4.84.23.63.62.43.34.75.56.15.95.45.76.05.32.72.62.82.40.80.70.80.70.50.50.50.23.82.72.92.63.12.84.52.92.92.54.02.82.62.82.91.92.3

us-gaap:AccountsReceivableNetCurrent us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

srt:GuarantorSubsidiaries, srt:ReportableLegalEntities


Accounts
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-12-31
Value4746314964708090819042
Percentage of AccountsReceivableNetCurrent93.792.587.593.891.486.287.099.699.299.599.4
Percentage of Assets3.43.32.13.14.34.75.35.95.35.62.7
Percentage of Assets srt:GuarantorSubsidiaries srt:ReportableLegalEntities3.93.92.64.15.25.85.97.06.87.64.3

srt:NonGuarantorSubsidiaries, srt:ReportableLegalEntities


Accounts
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-12-31
Value2.22.10.91.15.311120.30.20.40.3
Percentage of AccountsReceivableNetCurrent4.34.22.52.17.613.813.00.30.20.40.7
Percentage of Assets0.20.10.10.10.40.80.80.00.00.00.0
Percentage of Assets srt:NonGuarantorSubsidiaries srt:ReportableLegalEntities0.30.30.10.10.71.41.50.00.00.00.0

srt:ParentCompany, srt:ReportableLegalEntities


Accounts
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-12-31
Value1.01.73.62.20.70.00.00.10.50.10.0
Percentage of AccountsReceivableNetCurrent2.03.410.04.21.00.00.00.10.60.10.0
Percentage of Assets0.10.10.20.10.00.00.00.00.00.00.0
Percentage of Assets srt:ParentCompany srt:ReportableLegalEntities0.10.10.20.10.00.00.00.00.00.00.0

Inventory Net

us-gaap:InventoryNet

us-gaap:InventoryNet


Inventory
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
Value331303291267275317320322339327343390363330317261254244233233231220231298318297283241243252239231224156159159158170171165187163155
Percentage of InventoryNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets23.622.220.819.018.020.021.421.622.421.422.424.222.520.920.116.716.716.015.213.813.512.813.215.716.014.314.113.113.714.113.212.412.18.89.09.08.99.59.58.99.98.58.1

us-gaap:InventoryNet us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

srt:GuarantorSubsidiaries, srt:ReportableLegalEntities


Inventory
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-12-31
Value183178168187205199209202210236205
Percentage of InventoryNet63.166.761.359.264.161.761.861.961.360.564.6
Percentage of Assets13.112.711.111.813.713.313.813.213.714.613.0
Percentage of Assets srt:GuarantorSubsidiaries srt:ReportableLegalEntities15.014.814.015.416.816.415.515.817.519.620.7

srt:NonGuarantorSubsidiaries, srt:ReportableLegalEntities


Inventory
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-12-31
Value10789106129115123129124133154112
Percentage of InventoryNet36.933.338.740.835.938.338.238.138.739.535.3
Percentage of Assets7.76.37.08.27.78.38.68.18.79.67.1
Percentage of Assets srt:NonGuarantorSubsidiaries srt:ReportableLegalEntities13.711.513.515.914.215.515.815.015.617.412.2

Prepaid Expense And Other Assets Current

us-gaap:PrepaidExpenseAndOtherAssetsCurrent

us-gaap:PrepaidExpenseAndOtherAssetsCurrent


Prepaid
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302010-12-31
Value1817121414131223221818131514142118182231272942363623292925353240414134484343404418
Percentage of PrepaidExpenseAndOtherAssetsCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets1.31.30.91.01.00.80.81.61.51.21.20.91.00.90.91.41.21.21.41.91.61.72.41.91.81.11.51.61.42.01.82.22.22.32.02.72.42.42.22.41.0

us-gaap:PrepaidExpenseAndOtherAssetsCurrent us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

srt:GuarantorSubsidiaries, srt:ReportableLegalEntities


Prepaid
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-12-31
Value0.21.91.00.52.80.90.70.83.40.70.8
Percentage of PrepaidExpenseAndOtherAssetsCurrent1.613.16.83.723.03.93.24.418.95.05.4
Percentage of Assets0.00.10.10.00.20.10.00.10.20.00.1
Percentage of Assets srt:GuarantorSubsidiaries srt:ReportableLegalEntities0.00.20.10.00.20.10.10.10.30.10.1

srt:NonGuarantorSubsidiaries, srt:ReportableLegalEntities


Prepaid
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-12-31
Value9.28.59.18.06.410108.18.21210
Percentage of PrepaidExpenseAndOtherAssetsCurrent71.358.662.359.752.543.347.344.545.690.672.1
Percentage of Assets0.70.60.60.50.40.70.70.50.50.80.7
Percentage of Assets srt:NonGuarantorSubsidiaries srt:ReportableLegalEntities1.21.11.21.00.81.31.31.01.01.41.2

srt:ParentCompany, srt:ReportableLegalEntities


Prepaid
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-12-31
Value3.54.14.54.93.012119.36.40.63.3
Percentage of PrepaidExpenseAndOtherAssetsCurrent27.128.330.836.624.652.849.551.135.64.322.4
Percentage of Assets0.30.30.30.30.20.80.70.60.40.00.2
Percentage of Assets srt:ParentCompany srt:ReportableLegalEntities0.30.30.30.30.20.90.70.60.40.00.2

Machinery And Equipment Gross

us-gaap:MachineryAndEquipmentGross

us-gaap:MachineryAndEquipmentGross


Machinery
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-31
Value1506146714491398137413491395146414041387
Percentage of MachineryAndEquipmentGross100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets107.697.894.388.489.277.069.380.979.176.6

Noncurrent Assets

us-gaap:NoncurrentAssets us-gaap:StatementGeographical

us-gaap:NoncurrentAssets

cenx:Other


Noncurrent
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-31
Value687576747894
Percentage of NoncurrentAssets100.0100.0100.0100.0100.0100.0
Percentage of Assets4.95.05.04.75.15.4
Percentage of Assets cenx:Other0.00.00.00.00.00.0

country:IS


Noncurrent
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-31
Value511518554582625801
Percentage of NoncurrentAssets746.1687.9724.6777.8795.3848.6
Percentage of Assets36.634.536.136.940.645.7
Percentage of Assets country:IS0.00.00.00.00.00.0

country:US


Noncurrent
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-31
Value363419396370395408487392368
Percentage of NoncurrentAssets529.6556.6517.6493.7502.0432.90.00.00.0
Percentage of Assets26.027.925.823.425.723.324.221.720.8
Percentage of Assets country:US0.00.00.00.00.00.00.00.00.0

Property Plant And Equipment Gross

us-gaap:PropertyPlantAndEquipmentGross

us-gaap:PropertyPlantAndEquipmentGross


Property
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-31
Value19021890187417941768189120332042191718821857
Percentage of PropertyPlantAndEquipmentGross100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets135.9126.1121.9113.5114.8107.9100.9112.8108.0104.096.6

Construction In Progress Gross

us-gaap:ConstructionInProgressGross

us-gaap:ConstructionInProgressGross


Construction
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-31
Value1544462221173182221175162
Percentage of ConstructionInProgressGross100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets1.13.03.01.41.49.99.112.29.99.0

Accumulated Depreciation Depletion And Amortization Property Plant And Equipment

us-gaap:AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment

us-gaap:AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment


Accumulated
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-31
Value1022941907822742659741794729664600
Percentage of AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets73.062.859.052.048.237.636.843.941.136.731.2

Property Plant And Equipment Net

us-gaap:PropertyPlantAndEquipmentNet

us-gaap:PropertyPlantAndEquipmentNet


Property
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
Value868867880899919935949950951960967961947955971984100010121026118511971215123212511263128512911221123012391247123912301180118811971208120612181224123812461256
Percentage of PropertyPlantAndEquipmentNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets61.863.662.964.060.358.863.363.762.862.762.959.658.660.461.463.065.666.466.670.269.670.570.365.663.561.764.166.469.269.468.966.666.465.966.967.267.967.167.365.765.264.965.4

us-gaap:PropertyPlantAndEquipmentNet us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

srt:GuarantorSubsidiaries, srt:ReportableLegalEntities


Property
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-12-31
Value311319327332334326315318320309295
Percentage of PropertyPlantAndEquipmentNet35.435.535.735.635.334.333.233.233.232.230.4
Percentage of Assets22.222.821.520.922.321.920.820.820.919.218.7
Percentage of Assets srt:GuarantorSubsidiaries srt:ReportableLegalEntities25.426.527.227.327.327.023.424.826.625.829.8

srt:NonGuarantorSubsidiaries, srt:ReportableLegalEntities


Property
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-12-31
Value555565575586597605616621626630656
Percentage of PropertyPlantAndEquipmentNet63.162.862.662.762.963.864.864.764.765.667.6
Percentage of Assets39.740.237.836.839.840.640.740.640.739.141.5
Percentage of Assets srt:NonGuarantorSubsidiaries srt:ReportableLegalEntities70.772.673.172.073.976.175.074.673.270.971.5

srt:ParentCompany, srt:ReportableLegalEntities


Property
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-12-31
Value1314151617181920202119
Percentage of PropertyPlantAndEquipmentNet1.61.61.71.81.81.92.02.12.12.22.0
Percentage of Assets1.01.11.01.01.11.21.31.31.31.31.2
Percentage of Assets srt:ParentCompany srt:ReportableLegalEntities1.01.11.01.11.21.31.21.31.41.41.4

Investments In Affiliates Subsidiaries Associates And Joint Ventures

us-gaap:InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

us-gaap:InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures

srt:GuarantorSubsidiaries, srt:ReportableLegalEntities


Investments
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-12-31
Value6565656362575454545354
Percentage of InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets4.74.74.34.04.23.93.63.63.53.33.4
Percentage of Assets srt:GuarantorSubsidiaries srt:ReportableLegalEntities5.35.55.45.25.14.84.04.34.54.55.4

srt:ParentCompany, srt:ReportableLegalEntities


Investments
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-12-31
Value495533568583609625634648668772751
Percentage of InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures757.6810.0873.0921.6972.11083.41171.21182.71226.21438.21392.2
Percentage of Assets35.438.037.336.740.641.941.942.343.547.947.5
Percentage of Assets srt:ParentCompany srt:ReportableLegalEntities36.938.937.938.742.643.439.542.045.251.454.5

us-gaap:InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures us-gaap:ConsolidationItems

srt:ConsolidationEliminations


Investments
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-12-31
Value-560.9-599.7-633.4-646.7-672.2-682.8-689.0-702.9-722.8-826.0-805.8
Percentage of InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures-857.6-910.0-973.0-1021.6-1072.1-1183.4-1271.2-1282.7-1326.2-1538.2-1492.2
Percentage of Assets-40.1-42.7-41.6-40.6-44.8-45.8-45.5-45.9-47.0-51.2-50.9
Percentage of Assets srt:ConsolidationEliminations28.730.732.133.134.234.930.433.036.241.747.1

Operating Lease Right Of Use Asset

us-gaap:OperatingLeaseRightOfUseAsset

us-gaap:OperatingLeaseRightOfUseAsset


Operating
Period End2020-12-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value24252424240.0
Percentage of OperatingLeaseRightOfUseAsset100.0100.0100.0100.0100.00.0
Percentage of Assets1.81.71.61.61.60.0

Other Assets Noncurrent

us-gaap:OtherAssetsNoncurrent

us-gaap:OtherAssetsNoncurrent


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
Value585561616966624237626361625756676774737171737211112512412395939091108971011001201061041041131008582
Percentage of OtherAssetsNoncurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets4.24.04.44.34.64.24.22.82.54.14.13.83.83.63.54.34.44.94.84.24.24.24.15.96.36.06.15.25.25.15.15.85.35.65.76.76.05.85.86.15.34.44.3

us-gaap:OtherAssetsNoncurrent us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

srt:GuarantorSubsidiaries, srt:ReportableLegalEntities


Other
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-12-31
Value4.34.23.73.95.74.22.02.12.13434
Percentage of OtherAssetsNoncurrent7.06.95.35.89.110.05.33.43.356.060.8
Percentage of Assets0.30.30.20.20.40.30.10.10.12.12.2
Percentage of Assets srt:GuarantorSubsidiaries srt:ReportableLegalEntities0.40.30.30.30.50.30.10.20.22.93.4

srt:NonGuarantorSubsidiaries, srt:ReportableLegalEntities


Other
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-12-31
Value23181718182.44.130313025
Percentage of OtherAssetsNoncurrent37.430.925.727.230.15.710.848.149.849.046.2
Percentage of Assets1.61.31.21.11.30.20.32.02.11.91.6
Percentage of Assets srt:NonGuarantorSubsidiaries srt:ReportableLegalEntities2.92.42.32.22.30.30.53.63.73.42.8

srt:ParentCompany, srt:ReportableLegalEntities


Other
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-12-31
Value3438484438353130292928
Percentage of OtherAssetsNoncurrent55.662.269.066.960.884.383.948.646.947.650.0
Percentage of Assets2.42.73.22.82.52.42.12.01.91.81.8
Percentage of Assets srt:ParentCompany srt:ReportableLegalEntities2.52.83.23.02.72.52.02.02.02.02.0

Accrued Liabilities Current

us-gaap:AccruedLiabilitiesCurrent

us-gaap:AccruedLiabilitiesCurrent


Accrued
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
Value5462596976506566555952656468615645585059485048716710710446455169728149405244484058494641
Percentage of AccruedLiabilitiesCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets3.94.64.24.95.03.24.44.43.73.93.44.14.04.33.93.63.03.83.33.52.82.92.83.73.45.25.22.52.52.93.83.94.42.72.33.02.52.72.33.12.62.42.2

Liabilities Current

us-gaap:LiabilitiesCurrent

us-gaap:LiabilitiesCurrent


Liabilities
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
Value394364240201249284233212204229224230209197190195175185179174165158167232267315296217209242247278278201181198182189193213200242254
Percentage of LiabilitiesCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets28.126.717.214.316.417.915.614.213.515.014.614.313.012.512.012.511.512.211.610.49.69.29.512.213.515.114.711.811.813.613.715.015.011.210.211.210.210.510.711.410.512.613.3

us-gaap:LiabilitiesCurrent us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

srt:GuarantorSubsidiaries, srt:ReportableLegalEntities


Liabilities
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-12-31
Value1109810210311112710511712313589
Percentage of LiabilitiesCurrent45.849.040.936.247.660.151.751.354.858.746.9
Percentage of Assets7.97.06.76.57.48.57.07.78.08.45.7
Percentage of Assets srt:GuarantorSubsidiaries srt:ReportableLegalEntities9.08.28.58.59.110.57.89.210.211.39.0

srt:NonGuarantorSubsidiaries, srt:ReportableLegalEntities


Liabilities
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-12-31
Value7147517874375545565776
Percentage of LiabilitiesCurrent29.623.520.827.632.017.927.019.825.225.040.2
Percentage of Assets5.13.43.44.95.02.53.63.03.73.64.8
Percentage of Assets srt:NonGuarantorSubsidiaries srt:ReportableLegalEntities9.06.16.69.69.34.86.75.56.66.58.3

srt:ParentCompany, srt:ReportableLegalEntities


Liabilities
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-12-31
Value59559510347464366443724
Percentage of LiabilitiesCurrent24.627.638.336.320.422.121.328.919.916.412.9
Percentage of Assets4.23.96.36.53.23.12.94.32.92.31.6
Percentage of Assets srt:ParentCompany srt:ReportableLegalEntities4.44.06.46.83.33.32.74.33.02.51.8

Operating Lease Liability Current

us-gaap:OperatingLeaseLiabilityCurrent

us-gaap:OperatingLeaseLiabilityCurrent


Operating
Period End2020-12-312019-12-31
Value1600000.02800000.0
Percentage of OperatingLeaseLiabilityCurrent100.0100.0
Percentage of Assets0.10.2

Other Liabilities Current

us-gaap:OtherLiabilitiesCurrent us-gaap:CounterpartyName

us-gaap:OtherLiabilitiesCurrent

cenx:RavenswoodRetireeMedicalBenefitsChanges


Other
Period End2020-12-31
Value2000000.0
Percentage of OtherLiabilitiesCurrent100.0
Percentage of Assets0.1
Percentage of Assets cenx:RavenswoodRetireeMedicalBenefitsChanges0.0

Liabilities Noncurrent

us-gaap:LiabilitiesNoncurrent

us-gaap:LiabilitiesNoncurrent


Liabilities
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
Value640590613611625632591589601572551549554553561594599597604576559561567603604628626567563561559616604597611574576577579517521510513
Percentage of LiabilitiesNoncurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets45.643.343.843.541.139.739.439.539.737.435.834.134.335.035.538.039.339.239.234.132.632.632.431.630.430.231.130.931.731.430.933.132.633.434.532.232.432.132.027.827.526.626.7

us-gaap:LiabilitiesNoncurrent us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

srt:GuarantorSubsidiaries, srt:ReportableLegalEntities


Liabilities
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-12-31
Value527498466466464438609536452355216
Percentage of LiabilitiesNoncurrent86.181.474.673.778.574.4101.493.682.164.638.5
Percentage of Assets37.735.530.629.330.929.440.235.029.422.013.7
Percentage of Assets srt:GuarantorSubsidiaries srt:ReportableLegalEntities43.141.338.738.237.936.245.141.837.629.621.8

srt:NonGuarantorSubsidiaries, srt:ReportableLegalEntities


Liabilities
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-12-31
Value740742740738711719714714704716723
Percentage of LiabilitiesNoncurrent120.7121.4118.3116.8120.3122.1118.8124.8127.9130.3128.8
Percentage of Assets52.952.848.646.447.448.347.246.745.844.445.7
Percentage of Assets srt:NonGuarantorSubsidiaries srt:ReportableLegalEntities94.295.494.090.888.090.486.985.882.480.678.8

srt:ParentCompany, srt:ReportableLegalEntities


Liabilities
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-12-31
Value736726756731707703853749670632526
Percentage of LiabilitiesNoncurrent120.1118.7120.8115.7119.8119.4141.9130.9121.7115.093.7
Percentage of Assets52.651.749.646.047.247.256.349.043.639.233.3
Percentage of Assets srt:ParentCompany srt:ReportableLegalEntities54.952.850.448.549.548.953.148.645.442.038.1

us-gaap:LiabilitiesNoncurrent us-gaap:ConsolidationItems

srt:ConsolidationEliminations


Liabilities
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-12-31
Value-1391.3-1355.3-1337.2-1304.3-1292.0-1272.7-1576.0-1428.3-1276.5-1154.0-904.3
Percentage of LiabilitiesNoncurrent-226.9-221.5-213.7-206.2-218.6-215.9-262.1-249.4-231.7-209.9-161.1
Percentage of Assets-99.4-96.4-87.7-82.0-86.2-85.3-104.0-93.3-83.0-71.5-57.2
Percentage of Assets srt:ConsolidationEliminations71.369.367.966.965.865.169.667.063.858.352.9

Secured Long Term Debt

us-gaap:SecuredLongTermDebt us-gaap:DebtInstrument, us-gaap:LongtermDebtType

us-gaap:SecuredLongTermDebt

cenx:SeniorSecuredNotes120, us-gaap:SeniorNotes


Secured
Period End2020-12-31
Value243
Percentage of SecuredLongTermDebt100.0
Percentage of Assets17.4
Percentage of Assets cenx:SeniorSecuredNotes120 us-gaap:SeniorNotes0.0

cenx:SeniorSecuredNotes75, us-gaap:SeniorNotes


Secured
Period End2021-06-30
Value245
Percentage of SecuredLongTermDebt0.0
Percentage of Assets17.5
Percentage of Assets cenx:SeniorSecuredNotes75 us-gaap:SeniorNotes0.0

cenx:SeniorSecuredNotesDueJune012025, us-gaap:LongTermDebt


Secured
Period End2021-03-312020-12-312020-09-30
Value243243242
Percentage of SecuredLongTermDebt0.0100.00.0
Percentage of Assets17.917.417.3
Percentage of Assets cenx:SeniorSecuredNotesDueJune012025 us-gaap:LongTermDebt0.00.00.0

Deferred Income Tax Liabilities Net

us-gaap:DeferredIncomeTaxLiabilitiesNet

us-gaap:DeferredIncomeTaxLiabilitiesNet


Deferred
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value4286899494949598100102104
Percentage of DeferredIncomeTaxLiabilitiesNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets3.06.36.46.76.26.06.36.66.66.76.8

us-gaap:DeferredIncomeTaxLiabilitiesNet us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

srt:GuarantorSubsidiaries, srt:ReportableLegalEntities


Deferred
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value0.40.40.30.40.41.81.81.81.8
Percentage of DeferredIncomeTaxLiabilitiesNet0.40.40.30.40.41.81.81.81.7
Percentage of Assets0.00.00.00.00.00.10.10.10.1
Percentage of Assets srt:GuarantorSubsidiaries srt:ReportableLegalEntities0.00.00.00.00.00.10.10.10.1

srt:NonGuarantorSubsidiaries, srt:ReportableLegalEntities


Deferred
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value88949494949798100102
Percentage of DeferredIncomeTaxLiabilitiesNet99.699.699.799.699.698.598.498.598.5
Percentage of Assets6.36.76.25.96.36.56.56.66.7
Percentage of Assets srt:NonGuarantorSubsidiaries srt:ReportableLegalEntities11.312.112.011.611.712.212.012.112.0

Pension And Other Postretirement Defined Benefit Plans Liabilities Noncurrent

us-gaap:PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent us-gaap:RetirementPlanType

us-gaap:PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit


Pension
Period End2020-12-312019-12-312018-12-312017-12-312016-12-31
Value101100101113126
Percentage of PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent100.0100.0100.0100.0100.0
Percentage of Assets7.36.76.67.28.2
Percentage of Assets us-gaap:OtherPostretirementBenefitPlansDefinedBenefit0.00.00.00.00.0

us-gaap:PensionPlansDefinedBenefit


Pension
Period End2020-12-312019-12-312018-12-312017-12-312016-12-31
Value6560503849
Percentage of PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent64.260.450.334.439.2
Percentage of Assets4.74.13.32.53.2
Percentage of Assets us-gaap:PensionPlansDefinedBenefit0.00.00.00.00.0

Other Liabilities Noncurrent

us-gaap:OtherLiabilitiesNoncurrent

us-gaap:OtherLiabilitiesNoncurrent


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
Value47674446474742454748465057545762666472725351534746475338373637373725403939394040413437
Percentage of OtherLiabilitiesNoncurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets3.44.93.23.33.13.02.83.03.23.23.03.13.63.43.74.04.44.24.74.33.13.03.02.52.32.32.62.12.12.12.12.02.01.42.32.22.22.22.22.22.21.82.0

us-gaap:OtherLiabilitiesNoncurrent us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

srt:GuarantorSubsidiaries, srt:ReportableLegalEntities


Other
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-12-31
Value2424232122222222232432
Percentage of OtherLiabilitiesNoncurrent55.652.850.045.452.448.545.946.951.148.855.2
Percentage of Assets1.81.71.61.31.51.51.51.51.51.52.0
Percentage of Assets srt:GuarantorSubsidiaries srt:ReportableLegalEntities2.02.02.01.81.81.81.61.82.02.13.2

srt:NonGuarantorSubsidiaries, srt:ReportableLegalEntities


Other
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-12-31
Value1314172116171919192022
Percentage of OtherLiabilitiesNoncurrent30.831.036.846.339.438.541.540.942.840.738.7
Percentage of Assets1.01.01.21.41.11.21.31.31.31.31.4
Percentage of Assets srt:NonGuarantorSubsidiaries srt:ReportableLegalEntities1.81.82.22.72.12.22.42.42.32.32.4

srt:ParentCompany, srt:ReportableLegalEntities


Other
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-12-31
Value6.17.56.33.93.55.96.05.92.85.33.5
Percentage of OtherLiabilitiesNoncurrent13.616.213.28.38.313.012.512.26.110.46.0
Percentage of Assets0.40.50.40.20.20.40.40.40.20.30.2
Percentage of Assets srt:ParentCompany srt:ReportableLegalEntities0.50.50.40.30.20.40.40.40.20.40.3

Operating Lease Liability Noncurrent

us-gaap:OperatingLeaseLiabilityNoncurrent

us-gaap:OperatingLeaseLiabilityNoncurrent


Operating
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value232324232121222123220.0
Percentage of OperatingLeaseLiabilityNoncurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0
Percentage of Assets1.61.71.71.71.41.41.51.51.61.50.0

us-gaap:OperatingLeaseLiabilityNoncurrent us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

srt:GuarantorSubsidiaries, srt:ReportableLegalEntities


Operating
Period End2020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value0.0-0.00.10.40.20.30.3
Percentage of OperatingLeaseLiabilityNoncurrent0.0-0.00.51.80.91.31.3
Percentage of Assets0.0-0.00.00.00.00.00.0
Percentage of Assets srt:GuarantorSubsidiaries srt:ReportableLegalEntities0.0-0.00.00.00.00.00.0

srt:NonGuarantorSubsidiaries, srt:ReportableLegalEntities


Operating
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value1717161616161716
Percentage of OperatingLeaseLiabilityNoncurrent73.773.975.674.974.173.574.073.2
Percentage of Assets1.31.21.11.01.11.11.11.1
Percentage of Assets srt:NonGuarantorSubsidiaries srt:ReportableLegalEntities2.32.22.12.02.12.02.12.0

srt:ParentCompany, srt:ReportableLegalEntities


Operating
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value6.46.15.35.45.55.65.85.8
Percentage of OperatingLeaseLiabilityNoncurrent26.326.124.424.724.125.624.725.4
Percentage of Assets0.50.40.30.30.40.40.40.4
Percentage of Assets srt:ParentCompany srt:ReportableLegalEntities0.50.40.40.40.40.40.40.4

Lessee Operating Lease Liability Payments Due Year Two

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearTwo

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearTwo


Lessee
Period End2020-12-31
Value3000000.0
Percentage of LesseeOperatingLeaseLiabilityPaymentsDueYearTwo100.0
Percentage of Assets0.2

Lessee Operating Lease Liability Payments Due Year Three

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearThree

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearThree


Lessee
Period End2020-12-31
Value2700000.0
Percentage of LesseeOperatingLeaseLiabilityPaymentsDueYearThree100.0
Percentage of Assets0.2

Lessee Operating Lease Liability Payments Due Year Four

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFour

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFour


Lessee
Period End2020-12-31
Value2700000.0
Percentage of LesseeOperatingLeaseLiabilityPaymentsDueYearFour100.0
Percentage of Assets0.2

Lessee Operating Lease Liability Payments Due Year Five

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFive

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFive


Lessee
Period End2020-12-31
Value2700000.0
Percentage of LesseeOperatingLeaseLiabilityPaymentsDueYearFive100.0
Percentage of Assets0.2

Lessee Operating Lease Liability Payments Due After Year Five

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive


Lessee
Period End2020-12-31
Value29
Percentage of LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive100.0
Percentage of Assets2.1

Operating Lease Liability

us-gaap:OperatingLeaseLiability

us-gaap:OperatingLeaseLiability


Operating
Period End2020-12-312019-12-31
Value2525
Percentage of OperatingLeaseLiability100.0100.0
Percentage of Assets1.91.7

Lessee Operating Lease Liability Payments Due

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDue

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDue


Lessee
Period End2020-12-31
Value43
Percentage of LesseeOperatingLeaseLiabilityPaymentsDue100.0
Percentage of Assets3.1

Lessee Operating Lease Liability Undiscounted Excess Amount

us-gaap:LesseeOperatingLeaseLiabilityUndiscountedExcessAmount

us-gaap:LesseeOperatingLeaseLiabilityUndiscountedExcessAmount


Lessee
Period End2020-12-31
Value17
Percentage of LesseeOperatingLeaseLiabilityUndiscountedExcessAmount100.0
Percentage of Assets1.3

Stockholders Equity

us-gaap:StockholdersEquity

us-gaap:StockholdersEquity


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value370408546592648673675689709728762833853830829773750742756937994100210171071111611381091105410039831002965968992982100910201030103811321177116811541067
Percentage of StockholdersEquity100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets26.429.939.042.242.642.345.046.246.847.649.651.752.852.552.549.449.248.749.155.557.858.258.156.256.154.754.257.356.555.055.451.952.355.455.356.657.357.357.360.862.060.860.057.4

us-gaap:StockholdersEquity us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

srt:GuarantorSubsidiaries, srt:ReportableLegalEntities


Stockholders
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-12-31
Value586611637650650644636630629711687
Percentage of StockholdersEquity107.4103.298.396.596.393.489.786.682.685.382.9
Percentage of Assets41.943.541.940.943.343.242.041.240.944.143.5
Percentage of Assets srt:GuarantorSubsidiaries srt:ReportableLegalEntities47.950.652.953.353.153.247.149.152.259.269.2

srt:NonGuarantorSubsidiaries, srt:ReportableLegalEntities


Stockholders
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-12-31
Value-25.6-11.4-4.5-3.62238527293115118
Percentage of StockholdersEquity-4.7-1.9-0.7-0.53.35.67.410.012.313.814.2
Percentage of Assets-1.8-0.8-0.3-0.21.52.63.54.86.17.17.5
Percentage of Assets srt:NonGuarantorSubsidiaries srt:ReportableLegalEntities-3.3-1.5-0.6-0.42.74.96.48.711.012.912.9

srt:ParentCompany, srt:ReportableLegalEntities


Stockholders
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-12-31
Value546592648673675689709728762833829
Percentage of StockholdersEquity100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets39.042.242.642.345.046.246.847.649.651.752.5
Percentage of Assets srt:ParentCompany srt:ReportableLegalEntities40.743.143.244.747.247.944.247.151.655.460.1

us-gaap:StockholdersEquity us-gaap:ConsolidationItems

srt:ConsolidationEliminations


Stockholders
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-12-31
Value-560.9-599.7-633.4-646.7-672.2-682.8-689.0-702.9-722.8-826.1-805.8
Percentage of StockholdersEquity-102.7-101.2-97.6-96.0-99.6-99.0-97.1-96.5-94.8-99.1-97.1
Percentage of Assets-40.1-42.7-41.6-40.6-44.8-45.8-45.5-45.9-47.0-51.2-50.9
Percentage of Assets srt:ConsolidationEliminations28.730.732.133.134.234.930.433.036.241.747.1

us-gaap:StockholdersEquity us-gaap:StatementEquityComponents

us-gaap:AccumulatedDefinedBenefitPlansAdjustment


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-31
Value-118.1-119.3-120.6-108.3-109.5-110.3-111.7-100.0-100.7-101.7-100.7-90.7-90.8-93.4-93.88-114.141-115.225-115.431-116.181-108.082-108.944-109.806-110.667-99.92-96.335-115.735-115.852
Percentage of StockholdersEquity-31.9-29.2-22.1-18.3-16.9-16.4-16.5-14.5-14.2-14.0-13.2-10.9-10.6-11.2-11.3-14.8-15.3-15.5-15.4-11.5-11.0-10.9-10.9-9.3-8.6-10.2-10.6
Percentage of Assets-8.4-8.8-8.6-7.7-7.2-6.9-7.4-6.7-6.6-6.6-6.5-5.6-5.6-5.9-5.9-7.3-7.6-7.6-7.5-6.4-6.3-6.4-6.3-5.2-4.8-5.6-5.8
Percentage of Assets us-gaap:AccumulatedDefinedBenefitPlansAdjustment0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:AccumulatedGainLossNetCashFlowHedgeParent


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-31
Value1.71.81.81.81.91.91.92.02.02.02.02.12.12.12.12.3
Percentage of StockholdersEquity0.50.40.30.30.30.30.30.30.30.30.30.30.20.30.30.3
Percentage of Assets0.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.1
Percentage of Assets us-gaap:AccumulatedGainLossNetCashFlowHedgeParent0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:AccumulatedOtherComprehensiveIncome


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312013-12-312012-12-312011-12-312010-12-312009-12-31
Value-116.4-117.5-118.8-106.5-107.6-108.4-109.8-98.0-98.7-99.7-98.7-88.7-88.7-91.3-91.742-111.965-113.012-113.181-113.893-110.179-111.003-111.827-112.65-101.866-98.242-117.604-117.682-91.832-151.192-134.588-49.976-74.27
Percentage of StockholdersEquity-31.4-28.8-21.8-18.0-16.6-16.1-16.3-14.2-13.9-13.7-12.9-10.6-10.4-11.0-11.1-14.5-15.1-15.2-15.1-11.8-11.2-11.2-11.1-9.5-8.8-10.3-10.8-9.2-15.4-13.0-4.3-7.0
Percentage of Assets-8.3-8.6-8.5-7.6-7.1-6.8-7.3-6.6-6.5-6.5-6.4-5.5-5.5-5.8-5.8-7.2-7.4-7.4-7.4-6.5-6.5-6.5-6.4-5.3-4.9-5.6-5.8-5.1-8.5-7.4-2.6-4.0
Percentage of Assets us-gaap:AccumulatedOtherComprehensiveIncome0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:AdditionalPaidInCapital


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-312009-12-31
Value25272530253025282527252625262524252425232523251925182518251725152513251025082507250625032501
Percentage of StockholdersEquity682.2619.9463.3426.8389.6375.0374.3366.0355.8346.6331.0302.3295.3303.2303.4332.4247.0230.1250.2255.2241.4216.9234.3
Percentage of Assets179.8185.6180.8179.9165.9158.8168.5169.2166.6164.9164.1156.1155.8159.3159.2163.3143.4124.6138.6141.2138.4130.2134.4
Percentage of Assets us-gaap:AdditionalPaidInCapital0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:CommonStock


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-312009-12-31
Value1.01.01.01.01.01.01.01.01.01.01.00.90.90.90.9470.9440.9420.9390.9350.9330.9320.9280.925
Percentage of StockholdersEquity0.30.20.20.20.20.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.1
Percentage of Assets0.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.00.10.10.10.00.0
Percentage of Assets us-gaap:CommonStock0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:PreferredStock


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-312009-12-31
Value0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0010.0010.0010.0010.0010.0010.0010.0010.001
Percentage of StockholdersEquity0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0
Percentage of Assets0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0
Percentage of Assets us-gaap:PreferredStock0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:RetainedEarnings


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-312009-12-31
Value-1954.9-1919.8-1779.8-1744.2-1686.0-1659.1-1656.4-1651.6-1630.9-1610.1-1576.8-1511.9-1491.6-1511.0-1510.672-1559.252-1297.778-1252.448-1364.942-1324.629-1289.019-1300.344-1360.315
Percentage of StockholdersEquity-527.8-470.2-325.9-294.4-259.9-246.2-245.4-239.4-229.9-221.1-206.9-181.4-174.8-182.0-182.1-206.1-127.5-114.8-136.1-134.8-124.1-112.6-127.4
Percentage of Assets-139.1-140.8-127.2-124.1-110.6-104.3-110.4-110.7-107.6-105.2-102.6-93.7-92.3-95.6-95.5-101.2-74.1-62.2-75.4-74.6-71.2-67.6-73.1
Percentage of Assets us-gaap:RetainedEarnings0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:TreasuryStock


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-312009-12-31
Value-86.3-86.3-86.3-86.3-86.3-86.3-86.3-86.3-86.3-86.3-86.3-86.3-86.3-86.3-86.276-86.276-86.276-49.924-49.92449450.00.0
Percentage of StockholdersEquity-23.3-21.1-15.8-14.6-13.3-12.8-12.8-12.5-12.2-11.9-11.3-10.4-10.1-10.4-10.4-11.4-8.5-4.6-5.05.14.40.00.0
Percentage of Assets-6.1-6.3-6.2-6.1-5.7-5.4-5.8-5.8-5.7-5.6-5.6-5.3-5.3-5.5-5.5-5.6-4.9-2.5-2.82.82.50.00.0
Percentage of Assets us-gaap:TreasuryStock0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Common Stock Value

us-gaap:CommonStockValue

us-gaap:CommonStockValue


Common
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
Value1.01.01.01.01.01.01.01.01.01.01.00.90.90.90.9470.9450.9450.9440.9440.9420.9420.9420.9420.9410.9410.9390.9390.9370.9360.9360.9350.9350.9340.9340.9330.9330.9330.9320.9320.9320.9320.9310.928
Percentage of CommonStockValue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.00.00.00.00.10.10.10.10.10.10.10.10.10.10.10.10.10.00.00.0

us-gaap:CommonStockValue us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

srt:NonGuarantorSubsidiaries, srt:ReportableLegalEntities


Common
Period End2020-12-312020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-12-31
Value0.10.00.10.10.10.10.10.10.10.1
Percentage of CommonStockValue10.00.010.010.010.010.010.010.011.110.6
Percentage of Assets0.00.00.00.00.00.00.00.00.00.0
Percentage of Assets srt:NonGuarantorSubsidiaries srt:ReportableLegalEntities0.00.00.00.00.00.00.00.00.00.0

srt:ParentCompany, srt:ReportableLegalEntities


Common
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-12-31
Value1.01.01.01.01.01.01.01.01.00.90.9
Percentage of CommonStockValue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.095.0
Percentage of Assets0.10.10.10.10.10.10.10.10.10.10.1
Percentage of Assets srt:ParentCompany srt:ReportableLegalEntities0.10.10.10.10.10.10.10.10.10.10.1

us-gaap:CommonStockValue us-gaap:ConsolidationItems

srt:ConsolidationEliminations


Common
Period End2020-12-312020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-12-31
Value-0.10.0-0.1-0.1-0.1-0.1-0.1-0.1-0.1-0.1
Percentage of CommonStockValue-10.00.0-10.0-10.0-10.0-10.0-10.0-10.0-11.1-10.6
Percentage of Assets-0.00.0-0.0-0.0-0.0-0.0-0.0-0.0-0.0-0.0
Percentage of Assets srt:ConsolidationEliminations0.0-0.00.00.00.00.00.00.00.00.0

Additional Paid In Capital

us-gaap:AdditionalPaidInCapital

us-gaap:AdditionalPaidInCapital


Additional
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
Value2527253025302528252725262526252425242523252325192518251825172516251625152515251425142513251325132512251025102509250925082508250825072507250725072507250625062506250625042503
Percentage of AdditionalPaidInCapital100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets179.8185.6180.8179.9165.9158.8168.5169.2166.6164.9164.1156.1155.8159.3159.2161.0164.9164.9163.3148.9146.2145.9143.4131.8126.3120.5124.6136.4141.2140.4138.6134.9135.5140.0141.2140.6140.9139.5138.4134.5131.9130.4130.2

Retained Earnings Accumulated Deficit

us-gaap:RetainedEarningsAccumulatedDeficit

us-gaap:RetainedEarningsAccumulatedDeficit


Retained
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
Value-1954.9-1919.8-1779.8-1744.2-1686.0-1659.1-1656.4-1651.6-1630.9-1610.2-1576.8-1511.9-1491.6-1511.0-1510.672-1546.477-1567.26-1574.391-1559.252-1381.729-1323.456-1313.941-1297.778-1254.698-1212.566-1178.669-1252.448-1314.297-1364.702-1385.046-1364.942-1355.267-1350.949-1316.376-1324.629-1317.72-1305.697-1293.42-1289.019-1257.912-1251.312-1275.298-1300.344
Percentage of RetainedEarningsAccumulatedDeficit100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets-139.1-140.8-127.2-124.1-110.6-104.3-110.4-110.7-107.6-105.2-102.6-93.7-92.3-95.6-95.5-98.9-102.7-103.2-101.2-81.8-77.0-76.2-74.1-65.8-61.0-56.6-62.2-71.4-76.8-77.5-75.4-72.9-73.0-73.5-74.6-73.9-73.4-72.0-71.2-67.5-65.9-66.4-67.6

Accumulated Other Comprehensive Income Loss Net Of Tax

us-gaap:AccumulatedOtherComprehensiveIncomeLossNetOfTax

us-gaap:AccumulatedOtherComprehensiveIncomeLossNetOfTax


Accumulated
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
Value-116.4-117.5-118.8-106.5-107.6-108.4-109.8-98.0-98.7-99.7-98.7-88.7-88.7-91.3-91.742-111.965-113.012-113.181-113.893-110.179-111.003-111.827-112.65-101.866-98.242-117.604-117.682-92.017-91.864-91.733-91.832-138.68-139.163-150.297-151.192-130.893-132.067-133.832-134.588-77.901-78.234-61.333-49.976
Percentage of AccumulatedOtherComprehensiveIncomeLossNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets-8.3-8.6-8.5-7.6-7.1-6.8-7.3-6.6-6.5-6.5-6.4-5.5-5.5-5.8-5.8-7.2-7.4-7.4-7.4-6.5-6.5-6.5-6.4-5.3-4.9-5.6-5.8-5.0-5.2-5.1-5.1-7.5-7.5-8.4-8.5-7.3-7.4-7.4-7.4-4.2-4.1-3.2-2.6

Treasury Stock Value

us-gaap:TreasuryStockValue

us-gaap:TreasuryStockValue


Treasury
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302010-12-31
Value868686868686868686868686868686868686868686868686867649494949494949494949494945380.0
Percentage of TreasuryStockValue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0
Percentage of Assets6.16.36.26.15.75.45.85.85.75.65.65.35.35.55.55.55.75.75.65.15.05.04.94.54.33.72.52.72.82.82.82.72.72.82.82.82.82.82.52.10.0

Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value

us-gaap:AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue

us-gaap:AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue


Adjustments
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value700000.0900000.01600000.0800000.01100000.0100000.01600000.0500000.01000000.0300000.03600000.0700000.0700000.0700000.0
Percentage of AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue us-gaap:StatementEquityComponents

us-gaap:AdditionalPaidInCapital


Adjustments
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value700000.0900000.01600000.0800000.01100000.0100000.01600000.0500000.01000000.0300000.03500000.0700000.0700000.0700000.0
Percentage of AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.097.2100.0100.0100.0
Percentage of Assets0.00.00.00.00.00.00.00.00.00.00.00.00.00.0
Percentage of Assets us-gaap:AdditionalPaidInCapital0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:CommonStock


Adjustments
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-30
Value0000000000100000.00
Percentage of AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue0.00.00.00.00.00.00.00.00.00.02.80.0
Percentage of Assets0.00.00.00.00.00.00.00.00.00.00.00.0
Percentage of Assets us-gaap:CommonStock0.00.00.00.00.00.00.00.00.00.00.00.0

Net Cash Provided By Used In Operating Activities

us-gaap:NetCashProvidedByUsedInOperatingActivities

us-gaap:NetCashProvidedByUsedInOperatingActivities


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value-38.1-49.89.600000000000003-38.337342221-4.1-21.5-10.1-28.62.6-33.01.0924714-11.34422-8.0218.714-0.643-77.807-5.951116988919-10.741-22.74190.575221622-6.5134.898-14.0327-12.505-3.6331285021
Percentage of NetCashProvidedByUsedInOperatingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-7.2-11.22.5-9.79.28.25.14.8-0.9-4.4-2.1-5.90.6-7.30.311.93.7-3.16.6-2.42.74.7-0.2-17.1-1.119.817.917.84.2-2.6-5.74.90.27.05.17.5-2.01.5-4.47.9-3.4-1.19.810.117.57.6

us-gaap:NetCashProvidedByUsedInOperatingActivities us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

srt:GuarantorSubsidiaries, srt:ReportableLegalEntities


Net
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value-6.3-45.532346.4464.2-5.3-19.02.423-26.8-21.3
Percentage of NetCashProvidedByUsedInOperatingActivities-65.6118.888.498.629.0217.5-102.424.7188.1-8.4919.281.2-1950.5
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-1.6-11.68.18.11.510.50.9-1.1-3.90.55.1-5.9-4.9
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax srt:GuarantorSubsidiaries srt:ReportableLegalEntities-2.6-18.813.212.42.416.61.4-1.6-6.20.88.6-10.0-8.3

srt:NonGuarantorSubsidiaries, srt:ReportableLegalEntities


Net
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value1311121330-3.49.71.410-22.7-5.22034
Percentage of NetCashProvidedByUsedInOperatingActivities142.7-30.534.939.0137.1-16.0-236.6-6.5-105.979.4-200.0-62.43150.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax3.53.03.23.27.0-0.82.10.32.2-4.7-1.14.57.9
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax srt:NonGuarantorSubsidiaries srt:ReportableLegalEntities9.47.88.49.218.1-2.15.90.85.9-11.6-2.711.119.3

srt:ParentCompany, srt:ReportableLegalEntities


Net
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value2.2-4.5-8.6-13.0-14.6-21.5-18.0-17.6-1.8-8.3-16.1-26.8-9.0
Percentage of NetCashProvidedByUsedInOperatingActivities22.911.7-23.2-37.6-66.1-101.4439.081.917.829.0-619.281.2-824.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.6-1.1-2.1-3.1-3.4-4.9-3.8-3.6-0.4-1.7-3.4-5.9-2.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax srt:ParentCompany srt:ReportableLegalEntities0.00.00.00.00.00.00.00.00.00.00.00.00.0

Net Cash Provided By Used In Investing Activities

us-gaap:NetCashProvidedByUsedInInvestingActivities

us-gaap:NetCashProvidedByUsedInInvestingActivities


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value-18.5-7.4-0.4-1.9-3.6-5.9-9.4-16.6-2.2-10.6-33.6-36.3-9.5-3.5-8.217-4.075-9.8564.793-7.781-3.77-5.777-3.835-6.9433-36.159-33.639-69.119-14.48-10.606-14.852-23.248-22.869-60.151-10.906-5.453-5.837-19.52-1.721-11.879-4.48-1.357-7.1797.875-19.221-7.972-6.153
Percentage of NetCashProvidedByUsedInInvestingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-3.5-1.7-0.1-0.5-0.9-1.4-2.2-3.8-0.5-2.2-6.9-7.5-2.0-0.8-1.9-1.0-2.51.3-2.3-1.1-1.8-1.2-1.87.3-6.9-5.7-12.5-2.9-2.3-3.5-5.8-5.7-18.1-3.4-1.7-1.9-6.0-0.5-3.7-1.3-0.4-2.22.5-6.9-2.8-2.2

us-gaap:NetCashProvidedByUsedInInvestingActivities us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

srt:GuarantorSubsidiaries, srt:ReportableLegalEntities


Net
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value-12.617-29.6-35.025-33.2-21.3-24.5-12.4-2.75.1-0.430
Percentage of NetCashProvidedByUsedInInvestingActivities3150.0-894.7822.2593.2-272.3200.0968.2231.136.97.4-53.711.4-365.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-3.24.3-7.4-8.35.9-7.6-4.5-5.0-2.5-0.61.1-0.16.9
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax srt:GuarantorSubsidiaries srt:ReportableLegalEntities-5.27.0-11.9-12.89.6-12.0-6.9-7.5-4.1-0.91.8-0.111.8

srt:NonGuarantorSubsidiaries, srt:ReportableLegalEntities


Net
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value-1.31.4-0.6-0.37.8-0.63.3-3.1-4.4-3.1-2.1-1.6-4.0
Percentage of NetCashProvidedByUsedInInvestingActivities325.0-73.716.75.1-83.03.6-150.029.213.18.522.145.748.7
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-0.30.4-0.1-0.11.8-0.10.7-0.6-0.9-0.6-0.4-0.4-0.9
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax srt:NonGuarantorSubsidiaries srt:ReportableLegalEntities-0.90.9-0.4-0.24.7-0.42.0-1.9-2.4-1.6-1.1-0.9-2.2

srt:ParentCompany, srt:ReportableLegalEntities


Net
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value-8.4-23.87.5305212-7.0-15.8-18.32238-25.339
Percentage of NetCashProvidedByUsedInInvestingActivities2100.01252.6-208.3-515.3-559.6-77.7318.2149.154.5-62.0-403.2722.9-478.3
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-2.2-6.11.97.212.12.9-1.5-3.2-3.84.78.1-5.69.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax srt:ParentCompany srt:ReportableLegalEntities0.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:NetCashProvidedByUsedInInvestingActivities us-gaap:ConsolidationItems

srt:ConsolidationEliminations


Net
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value213.519-1.0-95.44.322321.5-53.0-50.823-73.6
Percentage of NetCashProvidedByUsedInInvestingActivities-5475.0-184.2-530.616.91014.9-25.9-1036.4-309.4-4.5146.0534.7-680.0895.7
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax5.60.94.8-0.2-21.91.04.86.70.3-11.0-10.85.2-17.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax srt:ConsolidationEliminations0.00.00.00.00.00.00.00.00.00.00.00.00.0

Net Cash Provided By Used In Financing Activities

us-gaap:NetCashProvidedByUsedInFinancingActivities

us-gaap:NetCashProvidedByUsedInFinancingActivities


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-30
Value390.4-10.0-52.5-5.0813.7-7.89.8159.2140.10.10.1230.0410.1970.0430.00.00.00.00.00.0-16.913-19.4390.254-2.580.123-5.997-10.72516-8.3640.00.00.00.0-4.033-7.085-38.755-47.2240.00.00.0
Percentage of NetCashProvidedByUsedInFinancingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.00.00.00.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.00.00.0100.0100.0100.0100.00.00.00.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax7.40.1-2.6-13.4-1.219.20.8-1.82.13.11.93.00.00.00.00.00.10.00.00.00.00.00.00.0-3.2-3.30.0-0.50.0-1.4-2.74.2-2.50.00.00.00.0-1.2-2.2-11.2-12.90.00.00.0

us-gaap:NetCashProvidedByUsedInFinancingActivities us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

srt:GuarantorSubsidiaries, srt:ReportableLegalEntities


Net
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value1828-3.01.9-31.9-12.81629310.1-29.027-8.6
Percentage of NetCashProvidedByUsedInFinancingActivities-189.0-54.360.02.3-862.2164.1172.4194.2344.60.7-29000.027200.0-6991.9
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax4.97.3-0.70.5-7.3-2.93.66.16.50.0-6.26.0-2.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax srt:GuarantorSubsidiaries srt:ReportableLegalEntities7.811.8-1.20.7-11.9-4.65.59.210.40.0-10.410.1-3.4

srt:NonGuarantorSubsidiaries, srt:ReportableLegalEntities


Net
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value-10.9-5.2-5.113-20.6-0.2-10.0-14.9-15.2-23.3-18.30.4-31.3
Percentage of NetCashProvidedByUsedInFinancingActivities109.09.9102.016.3-556.82.6-102.0-96.8-165.2-162.9-18300.0400.0-25447.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-2.8-1.3-1.33.1-4.7-0.0-2.1-3.0-3.1-4.8-3.90.1-7.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax srt:NonGuarantorSubsidiaries srt:ReportableLegalEntities-7.5-3.4-3.39.0-12.3-0.1-6.1-9.0-8.3-11.9-9.60.2-17.5

srt:ParentCompany, srt:ReportableLegalEntities


Net
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value3.9-72.32264-39.29.52533-5.8-15.5-3.4-3.7-36.6
Percentage of NetCashProvidedByUsedInFinancingActivities-39.0137.7-444.080.1-1059.5-121.8262.2215.6-63.0-108.4-3400.0-3700.0-29756.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax1.0-18.45.515.4-9.02.25.46.8-1.2-3.2-0.7-0.8-8.4
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax srt:ParentCompany srt:ReportableLegalEntities0.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:NetCashProvidedByUsedInFinancingActivities us-gaap:ConsolidationItems

srt:ConsolidationEliminations


Net
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value-21.9-3.5-19.11.095-4.3-22.8-32.8-1.55350-23.876
Percentage of NetCashProvidedByUsedInFinancingActivities219.06.7382.01.22578.455.1-232.7-213.0-16.3370.650800.0-23800.062276.4
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-5.6-0.9-4.80.221.9-1.0-4.8-6.7-0.311.010.8-5.217.7
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax srt:ConsolidationEliminations0.00.00.00.00.00.00.00.00.00.00.00.00.0

Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect


Cash
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value-17.3-56.8-0.8-92.72810916-3.23.5-16.7-34.5-50.6-6.8-36.4-7.1434.8-6.8
Percentage of CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-3.3-12.8-0.2-23.67.126.03.8-0.70.7-3.4-7.1-10.5-1.4-8.0-1.610.91.2-1.9

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

srt:GuarantorSubsidiaries, srt:ReportableLegalEntities


Cash
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value0.00.00.11.00.10.1-0.20.10.3-0.20.00.00.1
Percentage of CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect-0.0-0.00.40.90.6-3.1-5.7-0.6-0.90.4-0.0-0.0-1.4
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.00.00.00.20.00.0-0.00.00.1-0.00.00.00.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax srt:GuarantorSubsidiaries srt:ReportableLegalEntities0.00.00.00.40.00.0-0.10.00.1-0.10.00.00.0

srt:NonGuarantorSubsidiaries, srt:ReportableLegalEntities


Cash
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value1.57.97.22617-4.23.0-16.6-8.9-49.1-25.619-0.9
Percentage of CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect-187.5-8.525.424.1106.7131.285.799.425.897.0376.5-53.312.7
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.42.01.86.34.0-1.00.6-3.4-1.8-10.2-5.44.3-0.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax srt:NonGuarantorSubsidiaries srt:ReportableLegalEntities1.05.24.718.010.4-2.61.8-10.1-4.9-25.2-13.410.4-0.5

srt:ParentCompany, srt:ReportableLegalEntities


Cash
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value-2.3-100.62182-1.20.90.7-0.2-25.9-1.318-55.8-6.3
Percentage of CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect287.5108.574.375.0-7.3-28.120.01.275.12.6-276.5153.388.7
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-0.6-25.65.319.5-0.30.20.1-0.0-5.3-0.34.0-12.3-1.5
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax srt:ParentCompany srt:ReportableLegalEntities0.00.00.00.00.00.00.00.00.00.00.00.00.0

Depreciation Depletion And Amortization

us-gaap:DepreciationDepletionAndAmortization

us-gaap:DepreciationDepletionAndAmortization


Depreciation
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value20202121202020191824222322212120212021202121241918181717171717191315151515151515151516151515
Percentage of DepreciationDepletionAndAmortization100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Increase Decrease In Accounts Receivable

us-gaap:IncreaseDecreaseInAccountsReceivable

us-gaap:IncreaseDecreaseInAccountsReceivable


Increase
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value9.66.40.414-16.9-17.2-1.7-10.0-9.18.4-8.9-5.213402.704-2.1056.247231.245-3.1171.6363.1930.863-2.6966.343-72.70225-1.6776.635-10.5664.938-32.82311.9985.857-27.609212.884112.771-18.4557.527.47-2.286-1.3012.314
Percentage of IncreaseDecreaseInAccountsReceivable100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Increase Decrease In Inventories

us-gaap:IncreaseDecreaseInInventories

us-gaap:IncreaseDecreaseInInventories


Increase
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value281127-3.9-18.8101.3-14.625-16.4-16.0363210.0437.145124.677-2.1843.73615-17.648-91.288-14.239461415-1.897-8.59111-1.1080.514192.728-0.044-6.77-6.33-18.71598.195-23.54-7.924313.414-2.022-9.14
Percentage of IncreaseDecreaseInInventories100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Increase Decrease In Other Operating Capital Net

us-gaap:IncreaseDecreaseInOtherOperatingCapitalNet

us-gaap:IncreaseDecreaseInOtherOperatingCapitalNet


Increase
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value3.60.72.9-2.0-2.2-1.11.50.6-1.70.6-7.65.0-4.13.85.62-6.208-7.5793.585-1.102-1.456-2.191.648-2.48-3.3218.3280.604-6.1030.9172.56-0.064-15.24611-11.335-2.558-13.7812-0.369-0.33517-13.482.459-2.99821-2.6951.32-6.093
Percentage of IncreaseDecreaseInOtherOperatingCapitalNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Net Cash Provided By Used In Operating Activities

us-gaap:NetCashProvidedByUsedInOperatingActivities

us-gaap:NetCashProvidedByUsedInOperatingActivities


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value-38.1-49.89.600000000000003-38.337342221-4.1-21.5-10.1-28.62.6-33.01.0924714-11.34422-8.0218.714-0.643-77.807-5.951116988919-10.741-22.74190.575221622-6.5134.898-14.0327-12.505-3.6331285021
Percentage of NetCashProvidedByUsedInOperatingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-7.2-11.22.5-9.79.28.25.14.8-0.9-4.4-2.1-5.90.6-7.30.311.93.7-3.16.6-2.42.74.7-0.2-17.1-1.119.817.917.84.2-2.6-5.74.90.27.05.17.5-2.01.5-4.47.9-3.4-1.19.810.117.57.6

us-gaap:NetCashProvidedByUsedInOperatingActivities us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

srt:GuarantorSubsidiaries, srt:ReportableLegalEntities


Net
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value-6.3-45.532346.4464.2-5.3-19.02.423-26.8-21.3
Percentage of NetCashProvidedByUsedInOperatingActivities-65.6118.888.498.629.0217.5-102.424.7188.1-8.4919.281.2-1950.5
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-1.6-11.68.18.11.510.50.9-1.1-3.90.55.1-5.9-4.9
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax srt:GuarantorSubsidiaries srt:ReportableLegalEntities-2.6-18.813.212.42.416.61.4-1.6-6.20.88.6-10.0-8.3

srt:NonGuarantorSubsidiaries, srt:ReportableLegalEntities


Net
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value1311121330-3.49.71.410-22.7-5.22034
Percentage of NetCashProvidedByUsedInOperatingActivities142.7-30.534.939.0137.1-16.0-236.6-6.5-105.979.4-200.0-62.43150.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax3.53.03.23.27.0-0.82.10.32.2-4.7-1.14.57.9
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax srt:NonGuarantorSubsidiaries srt:ReportableLegalEntities9.47.88.49.218.1-2.15.90.85.9-11.6-2.711.119.3

srt:ParentCompany, srt:ReportableLegalEntities


Net
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value2.2-4.5-8.6-13.0-14.6-21.5-18.0-17.6-1.8-8.3-16.1-26.8-9.0
Percentage of NetCashProvidedByUsedInOperatingActivities22.911.7-23.2-37.6-66.1-101.4439.081.917.829.0-619.281.2-824.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.6-1.1-2.1-3.1-3.4-4.9-3.8-3.6-0.4-1.7-3.4-5.9-2.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax srt:ParentCompany srt:ReportableLegalEntities0.00.00.00.00.00.00.00.00.00.00.00.00.0

Net Income Loss

us-gaap:NetIncomeLoss

us-gaap:NetIncomeLoss


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value-35.1-140.0-35.5-58.2-26.9-2.7-4.8-20.7-20.7-34.6-65.0-20.319-0.335207.131-15.139-168.464-58.273-9.515-16.163-43.08-56.112-33.89773615020-20.104-9.675-9.507-34.5738.253-6.909-12.023-12.277-4.401-31.107-6.6232565-16.7875.1466.332
Percentage of NetIncomeLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-6.6-31.5-9.1-14.8-6.7-0.6-1.1-4.7-4.4-7.1-13.3-4.24.1-0.18.35.21.8-4.1-49.6-17.5-2.9-5.1-11.2-12.3-6.512.511.210.14.4-4.8-2.4-2.4-10.42.6-2.2-3.9-3.8-1.3-9.8-1.96.57.720.6-6.01.82.2

us-gaap:NetIncomeLoss us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

srt:GuarantorSubsidiaries, srt:ReportableLegalEntities


Net
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value-17.8-27.4-13.3-3.7-1.2-5.44.10.3-53.7-9.7208.91318
Percentage of NetIncomeLoss50.147.149.4137.025.026.1-19.8-0.982.647.8105.2-2966.738.087.6
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-4.6-7.0-3.3-0.9-0.3-1.20.90.1-11.0-2.04.32.03.14.5
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax srt:GuarantorSubsidiaries srt:ReportableLegalEntities-7.3-11.3-5.4-1.3-0.4-1.91.30.1-17.6-3.47.33.35.37.6

srt:NonGuarantorSubsidiaries, srt:ReportableLegalEntities


Net
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value-11.5-7.5-1.1-26.1-14.1-14.7-21.5-20.9-25.5-4.13.4-4.01113
Percentage of NetIncomeLoss32.412.94.1966.7293.871.0103.960.439.220.217.51333.331.365.9
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-3.0-1.9-0.3-6.2-3.2-3.4-4.5-4.3-5.2-0.90.7-0.92.63.4
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax srt:NonGuarantorSubsidiaries srt:ReportableLegalEntities-7.9-5.0-0.7-17.8-8.4-9.1-13.1-12.7-14.0-2.11.8-2.16.38.5

srt:ParentCompany, srt:ReportableLegalEntities


Net
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value-35.5-58.2-26.9-2.8-4.8-20.7-20.7-34.6-65.0-20.319-0.33520
Percentage of NetIncomeLoss100.0100.0100.0103.7100.0100.0100.0100.0100.0100.0100.0100.0100.0100.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-9.1-14.8-6.7-0.7-1.1-4.7-4.4-7.1-13.3-4.24.1-0.18.35.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax srt:ParentCompany srt:ReportableLegalEntities0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:NetIncomeLoss us-gaap:ConsolidationItems

srt:ConsolidationEliminations


Net
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value29341429152017207913-23.8-4.9-24.8-31.9
Percentage of NetIncomeLoss-82.5-60.0-53.5-1107.4-318.8-97.1-84.1-59.5-121.8-68.0-122.71633.3-69.3-153.5
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax7.58.93.67.13.54.63.74.216.32.9-5.1-1.1-5.7-8.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax srt:ConsolidationEliminations0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:NetIncomeLoss us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:StatementEquityComponents

us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:AccumulatedDefinedBenefitPlansAdjustment


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
Value-1.2-1.3-5.5-1.2-0.8-1.4-7.6-0.7-1.0-0.3-2.70.12.6-0.44.137-1.0840.2060.751.4220.8620.8620.861-4.130.5291.3580.1175.455-0.098-0.5170.1550.3970.5380.840.95
Percentage of NetIncomeLoss3.40.915.52.13.051.9158.33.44.80.94.2-0.513.4133.311.6-5.22.9-5.0-0.8-1.5-9.1-5.39.6-0.9-4.00.28.8-0.2-2.5-0.8-4.1-5.7-2.411.5
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-0.2-0.3-1.4-0.3-0.2-0.3-1.7-0.2-0.2-0.1-0.60.00.6-0.11.0-0.30.10.20.40.30.30.3-1.10.10.30.01.0-0.0-0.10.00.10.10.30.3
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome us-gaap:AccumulatedDefinedBenefitPlansAdjustment0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:AccumulatedGainLossNetCashFlowHedgeParent


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value0.1-0.0-0.20.10.00.0-0.20.00.00.0-0.30.00.00.0
Percentage of NetIncomeLoss-0.30.00.6-0.2-0.0-0.04.2-0.0-0.0-0.00.5-0.00.0-0.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.0-0.0-0.10.00.00.0-0.00.00.00.0-0.10.00.00.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome us-gaap:AccumulatedGainLossNetCashFlowHedgeParent0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:NetIncomeLoss us-gaap:StatementEquityComponents

us-gaap:RetainedEarnings


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value-35.1-140.0-35.5-58.2-26.9-2.7-4.8-20.7-20.7-34.6-20.319-0.3
Percentage of NetIncomeLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-6.6-31.5-9.1-14.8-6.7-0.6-1.1-4.7-4.4-7.1-4.24.1-0.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:RetainedEarnings0.00.00.00.00.00.00.00.00.00.00.00.00.0

Net Cash Provided By Used In Investing Activities

us-gaap:NetCashProvidedByUsedInInvestingActivities

us-gaap:NetCashProvidedByUsedInInvestingActivities


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value-18.5-7.4-0.4-1.9-3.6-5.9-9.4-16.6-2.2-10.6-33.6-36.3-9.5-3.5-8.217-4.075-9.8564.793-7.781-3.77-5.777-3.835-6.9433-36.159-33.639-69.119-14.48-10.606-14.852-23.248-22.869-60.151-10.906-5.453-5.837-19.52-1.721-11.879-4.48-1.357-7.1797.875-19.221-7.972-6.153
Percentage of NetCashProvidedByUsedInInvestingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-3.5-1.7-0.1-0.5-0.9-1.4-2.2-3.8-0.5-2.2-6.9-7.5-2.0-0.8-1.9-1.0-2.51.3-2.3-1.1-1.8-1.2-1.87.3-6.9-5.7-12.5-2.9-2.3-3.5-5.8-5.7-18.1-3.4-1.7-1.9-6.0-0.5-3.7-1.3-0.4-2.22.5-6.9-2.8-2.2

us-gaap:NetCashProvidedByUsedInInvestingActivities us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

srt:GuarantorSubsidiaries, srt:ReportableLegalEntities


Net
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value-12.617-29.6-35.025-33.2-21.3-24.5-12.4-2.75.1-0.430
Percentage of NetCashProvidedByUsedInInvestingActivities3150.0-894.7822.2593.2-272.3200.0968.2231.136.97.4-53.711.4-365.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-3.24.3-7.4-8.35.9-7.6-4.5-5.0-2.5-0.61.1-0.16.9
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax srt:GuarantorSubsidiaries srt:ReportableLegalEntities-5.27.0-11.9-12.89.6-12.0-6.9-7.5-4.1-0.91.8-0.111.8

srt:NonGuarantorSubsidiaries, srt:ReportableLegalEntities


Net
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value-1.31.4-0.6-0.37.8-0.63.3-3.1-4.4-3.1-2.1-1.6-4.0
Percentage of NetCashProvidedByUsedInInvestingActivities325.0-73.716.75.1-83.03.6-150.029.213.18.522.145.748.7
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-0.30.4-0.1-0.11.8-0.10.7-0.6-0.9-0.6-0.4-0.4-0.9
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax srt:NonGuarantorSubsidiaries srt:ReportableLegalEntities-0.90.9-0.4-0.24.7-0.42.0-1.9-2.4-1.6-1.1-0.9-2.2

srt:ParentCompany, srt:ReportableLegalEntities


Net
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value-8.4-23.87.5305212-7.0-15.8-18.32238-25.339
Percentage of NetCashProvidedByUsedInInvestingActivities2100.01252.6-208.3-515.3-559.6-77.7318.2149.154.5-62.0-403.2722.9-478.3
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-2.2-6.11.97.212.12.9-1.5-3.2-3.84.78.1-5.69.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax srt:ParentCompany srt:ReportableLegalEntities0.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:NetCashProvidedByUsedInInvestingActivities us-gaap:ConsolidationItems

srt:ConsolidationEliminations


Net
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value213.519-1.0-95.44.322321.5-53.0-50.823-73.6
Percentage of NetCashProvidedByUsedInInvestingActivities-5475.0-184.2-530.616.91014.9-25.9-1036.4-309.4-4.5146.0534.7-680.0895.7
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax5.60.94.8-0.2-21.91.04.86.70.3-11.0-10.85.2-17.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax srt:ConsolidationEliminations0.00.00.00.00.00.00.00.00.00.00.00.00.0

Payments To Acquire Property Plant And Equipment

us-gaap:PaymentsToAcquirePropertyPlantAndEquipment

us-gaap:PaymentsToAcquirePropertyPlantAndEquipment


Payments
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value187.41.91.93.66.01916121033369.53.58.2494.7479.7989.0458.8175.3933.8993.8351611151014107.0589.714157.2019.3647.2784.2343.2662.8999.2323.5154.2253.1286.8632.3662.040.972
Percentage of PaymentsToAcquirePropertyPlantAndEquipment100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PaymentsToAcquirePropertyPlantAndEquipment us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

srt:GuarantorSubsidiaries, srt:ReportableLegalEntities


Payments
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value1.11.02.75.617145.46.826335.10.42.2
Percentage of PaymentsToAcquirePropertyPlantAndEquipment57.952.675.093.386.385.542.564.277.792.053.711.426.7

srt:NonGuarantorSubsidiaries, srt:ReportableLegalEntities


Payments
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value0.80.60.50.32.62.47.33.27.13.11.71.63.9
Percentage of PaymentsToAcquirePropertyPlantAndEquipment42.131.613.95.013.214.557.530.221.18.517.945.747.3

srt:ParentCompany, srt:ReportableLegalEntities


Payments
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value0.00.30.40.10.10.00.00.60.4-0.22.71.52.1
Percentage of PaymentsToAcquirePropertyPlantAndEquipment0.015.811.11.70.50.00.05.71.2-0.628.442.925.5

Net Cash Provided By Used In Financing Activities

us-gaap:NetCashProvidedByUsedInFinancingActivities

us-gaap:NetCashProvidedByUsedInFinancingActivities


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-30
Value390.4-10.0-52.5-5.0813.7-7.89.8159.2140.10.10.1230.0410.1970.0430.00.00.00.00.00.0-16.913-19.4390.254-2.580.123-5.997-10.72516-8.3640.00.00.00.0-4.033-7.085-38.755-47.2240.00.00.0
Percentage of NetCashProvidedByUsedInFinancingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.00.00.00.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.00.00.0100.0100.0100.0100.00.00.00.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax7.40.1-2.6-13.4-1.219.20.8-1.82.13.11.93.00.00.00.00.00.10.00.00.00.00.00.00.0-3.2-3.30.0-0.50.0-1.4-2.74.2-2.50.00.00.00.0-1.2-2.2-11.2-12.90.00.00.0

us-gaap:NetCashProvidedByUsedInFinancingActivities us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

srt:GuarantorSubsidiaries, srt:ReportableLegalEntities


Net
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value1828-3.01.9-31.9-12.81629310.1-29.027-8.6
Percentage of NetCashProvidedByUsedInFinancingActivities-189.0-54.360.02.3-862.2164.1172.4194.2344.60.7-29000.027200.0-6991.9
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax4.97.3-0.70.5-7.3-2.93.66.16.50.0-6.26.0-2.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax srt:GuarantorSubsidiaries srt:ReportableLegalEntities7.811.8-1.20.7-11.9-4.65.59.210.40.0-10.410.1-3.4

srt:NonGuarantorSubsidiaries, srt:ReportableLegalEntities


Net
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value-10.9-5.2-5.113-20.6-0.2-10.0-14.9-15.2-23.3-18.30.4-31.3
Percentage of NetCashProvidedByUsedInFinancingActivities109.09.9102.016.3-556.82.6-102.0-96.8-165.2-162.9-18300.0400.0-25447.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-2.8-1.3-1.33.1-4.7-0.0-2.1-3.0-3.1-4.8-3.90.1-7.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax srt:NonGuarantorSubsidiaries srt:ReportableLegalEntities-7.5-3.4-3.39.0-12.3-0.1-6.1-9.0-8.3-11.9-9.60.2-17.5

srt:ParentCompany, srt:ReportableLegalEntities


Net
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value3.9-72.32264-39.29.52533-5.8-15.5-3.4-3.7-36.6
Percentage of NetCashProvidedByUsedInFinancingActivities-39.0137.7-444.080.1-1059.5-121.8262.2215.6-63.0-108.4-3400.0-3700.0-29756.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax1.0-18.45.515.4-9.02.25.46.8-1.2-3.2-0.7-0.8-8.4
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax srt:ParentCompany srt:ReportableLegalEntities0.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:NetCashProvidedByUsedInFinancingActivities us-gaap:ConsolidationItems

srt:ConsolidationEliminations


Net
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value-21.9-3.5-19.11.095-4.3-22.8-32.8-1.55350-23.876
Percentage of NetCashProvidedByUsedInFinancingActivities219.06.7382.01.22578.455.1-232.7-213.0-16.3370.650800.0-23800.062276.4
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-5.6-0.9-4.80.221.9-1.0-4.8-6.7-0.311.010.8-5.217.7
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax srt:ConsolidationEliminations0.00.00.00.00.00.00.00.00.00.00.00.00.0

Debt Instrument Interest Rate Stated Percentage

us-gaap:DebtInstrumentInterestRateStatedPercentage us-gaap:DebtInstrument, us-gaap:LongtermDebtType

us-gaap:DebtInstrumentInterestRateStatedPercentage

cenx:EOnContingentObligation, us-gaap:LongTermDebt


Debt
Period End2020-12-312019-12-312018-12-312017-12-31
Value10.940.10940.10940.1094
Percentage of DebtInstrumentInterestRateStatedPercentage100.0100.0100.0100.0
Percentage of LongTermDebtAndCapitalLeaseObligations0.00.00.00.0
Percentage of LongTermDebtAndCapitalLeaseObligations cenx:EOnContingentObligation us-gaap:LongTermDebt0.00.00.00.0

cenx:SeniorSecuredNotesDueJune012025, us-gaap:LongTermDebt


Debt
Period End2020-12-31
Value12.0
Percentage of DebtInstrumentInterestRateStatedPercentage109.7
Percentage of LongTermDebtAndCapitalLeaseObligations0.0
Percentage of LongTermDebtAndCapitalLeaseObligations cenx:SeniorSecuredNotesDueJune012025 us-gaap:LongTermDebt0.0

Deferred Tax Liabilities

us-gaap:DeferredTaxLiabilities

us-gaap:DeferredTaxLiabilities


Deferred
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-31
Value89941021001059610194251157181
Percentage of DeferredTaxLiabilities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Deferred Tax Assets Net

us-gaap:DeferredTaxAssetsNet

us-gaap:DeferredTaxAssetsNet


Deferred
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-31
Value5.7111.89.197155385991586695
Percentage of DeferredTaxAssetsNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Unrecognized Tax Benefits

us-gaap:UnrecognizedTaxBenefits

us-gaap:UnrecognizedTaxBenefits


Unrecognized
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312012-09-302012-06-302012-03-312011-12-312010-12-312009-12-312008-12-31
Value6.58.29.58.46.43.82.01.21717161615162121
Percentage of UnrecognizedTaxBenefits100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Deferred Tax Assets Valuation Allowance

us-gaap:DeferredTaxAssetsValuationAllowance

us-gaap:DeferredTaxAssetsValuationAllowance


Deferred
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-31
Value499492552607839768748765656773714
Percentage of DeferredTaxAssetsValuationAllowance100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DeferredTaxAssetsValuationAllowance us-gaap:ValuationAllowanceByDeferredTaxAsset

cenx:AllU.S.andPortionofIcelandicDeferredTaxAssets


Deferred
Period End2020-12-312019-12-312018-12-312017-12-312016-12-31
Value499492552607839
Percentage of DeferredTaxAssetsValuationAllowance100.0100.0100.0100.0100.0

cenx:AdjustmentsToAdditionalPaidInCapitalOptionIndexedToIssuersEquityCappedCallPremium

cenx:AdjustmentsToAdditionalPaidInCapitalOptionIndexedToIssuersEquityCappedCallPremium


Adjustments
Period End2021-06-30
Value4600000.0
Percentage of AdjustmentsToAdditionalPaidInCapitalOptionIndexedToIssuersEquityCappedCallPremium100.0

cenx:AdjustmentsToAdditionalPaidInCapitalOptionIndexedToIssuersEquityCappedCallPremium us-gaap:StatementEquityComponents

us-gaap:AdditionalPaidInCapital


Adjustments
Period End2021-06-30
Value4600000.0
Percentage of AdjustmentsToAdditionalPaidInCapitalOptionIndexedToIssuersEquityCappedCallPremium100.0

cenx:CapitalExpendituresNonCashInvestingActivity

cenx:CapitalExpendituresNonCashInvestingActivity


Capital
Period End2021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value1800000.0-200000.0-600000.01200000.01800000.0-1900000.04000000.0-100000.06600000.00
Percentage of CapitalExpendituresNonCashInvestingActivity100.0100.0100.0100.0100.0100.0100.0100.0100.00.0

cenx:DiscreteTaxBenefitExpense us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName

cenx:DiscreteTaxBenefitExpense

cenx:Helguvik


Discrete
Period End2021-06-30
Value49
Percentage of DiscreteTaxBenefitExpense100.0

cenx:EquityInEarningsOfJointVenture

cenx:EquityInEarningsOfJointVenture


Equity
Period End2021-06-302020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-30
Value0.00.00.00.00.00.10.50.72.0
Percentage of EquityInEarningsOfJointVenture0.00.00.00.00.0100.0100.0100.0100.0

cenx:EquityInEarningsOfJointVenture us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

srt:GuarantorSubsidiaries, srt:ReportableLegalEntities


Equity
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-30
Value0.81.90.53.4-0.60.32.8-2.7
Percentage of EquityInEarningsOfJointVenture0.00.00.00.0-600.060.0400.0-135.0

srt:ParentCompany, srt:ReportableLegalEntities


Equity
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-30
Value-35.7-16.3-30.4-23.4-16.8-20.9-16.626
Percentage of EquityInEarningsOfJointVenture0.00.00.00.0-16800.0-4180.0-2371.41325.0

cenx:EquityInEarningsOfJointVenture us-gaap:ConsolidationItems

srt:ConsolidationEliminations


Equity
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-30
Value34142920172013-23.8
Percentage of EquityInEarningsOfJointVenture0.00.00.00.017400.04120.01971.4-1190.0

cenx:FairValueNetDerivativeAssetLiabilityMeasuredonRecurringBasisUnobservableInputsReconciliationUnrealizedGainsLosses us-gaap:DerivativeInstrumentRisk

cenx:FairValueNetDerivativeAssetLiabilityMeasuredonRecurringBasisUnobservableInputsReconciliationUnrealizedGainsLosses

cenx:FXSwap


Fair
Period End2021-06-302019-12-312019-09-302019-06-302019-03-31
Value0.00.10.00.0-0.3
Percentage of FairValueNetDerivativeAssetLiabilityMeasuredonRecurringBasisUnobservableInputsReconciliationUnrealizedGainsLosses0.0100.00.00.0100.0

cenx:FixedtoVariableLondonMetalsExchangeSwap


Fair
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-31
Value-11.6-8.7-2.3-4.2-1.76.7
Percentage of FairValueNetDerivativeAssetLiabilityMeasuredonRecurringBasisUnobservableInputsReconciliationUnrealizedGainsLosses0.00.00.00.00.00.0

cenx:HawesvilleL4PowerPriceSwaps


Fair
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-30
Value0.80.71.7-0.31.21.2-2.7
Percentage of FairValueNetDerivativeAssetLiabilityMeasuredonRecurringBasisUnobservableInputsReconciliationUnrealizedGainsLosses0.00.00.00.01200.00.00.0

cenx:NordpoolPowerPriceSwap


Fair
Period End2021-06-302019-12-312019-09-302019-06-302019-03-31
Value0.0-0.10.00.0-1.0
Percentage of FairValueNetDerivativeAssetLiabilityMeasuredonRecurringBasisUnobservableInputsReconciliationUnrealizedGainsLosses0.0-100.00.00.0333.3

cenx:GainLossOnExtinguishmentOfDebtNet

cenx:GainLossOnExtinguishmentOfDebtNet


Gain
Period End2020-12-31
Value0
Percentage of GainLossOnExtinguishmentOfDebtNet0.0

cenx:IncomeLossAfterIncomeTaxesBeforeIncomeLossFromEquityMethodInvestments

cenx:IncomeLossAfterIncomeTaxesBeforeIncomeLossFromEquityMethodInvestments


Income
Period End2021-06-302020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value-35.1-35.4-58.2-26.9-2.7-4.7-20.7-16.5-35.1-66.0-21.017-0.935207.379-15.61-168.847-58.428-9.894-16.52-32.099-56.816-34.75273615019-19.609-10.219-10.238-35.0097.302-7.416-13.149-12.626-5.042-31.966-7.507232364-17.974.6695.227
Percentage of IncomeLossAfterIncomeTaxesBeforeIncomeLossFromEquityMethodInvestments100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cenx:IncomeLossAfterIncomeTaxesBeforeIncomeLossFromEquityMethodInvestments us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

srt:GuarantorSubsidiaries, srt:ReportableLegalEntities


Income
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value-17.300000000000008-28.2-15.2-4.2-6.3-8.84.70.0-54.6-12.5239.21416
Percentage of IncomeLossAfterIncomeTaxesBeforeIncomeLossFromEquityMethodInvestments48.948.556.5155.6134.042.5-28.5-0.082.759.5132.8-1022.241.781.7

srt:NonGuarantorSubsidiaries, srt:ReportableLegalEntities


Income
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value-11.4-7.5-1.1-26.1-14.0-14.6-17.3-21.4-26.5-4.81.4-4.61013
Percentage of IncomeLossAfterIncomeTaxesBeforeIncomeLossFromEquityMethodInvestments32.212.94.1966.7297.970.5104.861.040.222.98.0511.130.765.6

srt:ParentCompany, srt:ReportableLegalEntities


Income
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value-6.7-22.5-10.627152.7-3.9-13.715-3.7-7.1-5.59.8-9.7
Percentage of IncomeLossAfterIncomeTaxesBeforeIncomeLossFromEquityMethodInvestments18.938.739.4-1022.2-331.9-13.023.639.0-22.917.6-40.8611.127.6-47.2

cenx:IncomeLossBeforeIncomeTaxesAndEquityMethodInvestmentsInNoncontrollingInterest

cenx:IncomeLossBeforeIncomeTaxesAndEquityMethodInvestmentsInNoncontrollingInterest


Income
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value-36.9-57.9-26.0-5.5-7.4-22.0-18.1-38.0
Percentage of IncomeLossBeforeIncomeTaxesAndEquityMethodInvestmentsInNoncontrollingInterest100.0100.0100.0100.0100.0100.0100.0100.0

cenx:IncomeLossBeforeIncomeTaxesAndEquityMethodInvestmentsInNoncontrollingInterest us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

srt:GuarantorSubsidiaries, srt:ReportableLegalEntities


Income
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value-17.300000000000008-28.2-15.2-4.2-7.7-8.84.70.0
Percentage of IncomeLossBeforeIncomeTaxesAndEquityMethodInvestmentsInNoncontrollingInterest46.948.758.576.4104.140.0-26.0-0.0

srt:NonGuarantorSubsidiaries, srt:ReportableLegalEntities


Income
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value-12.7-7.20.3-28.4-15.7-15.2-19.0-23.3
Percentage of IncomeLossBeforeIncomeTaxesAndEquityMethodInvestmentsInNoncontrollingInterest34.412.4-1.2516.4212.269.1105.061.3

srt:ParentCompany, srt:ReportableLegalEntities


Income
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value-6.9-22.5-11.127162.0-3.8-14.7
Percentage of IncomeLossBeforeIncomeTaxesAndEquityMethodInvestmentsInNoncontrollingInterest18.738.942.7-492.7-216.2-9.121.038.7

cenx:InterestExpenseIntercompany us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

cenx:InterestExpenseIntercompany

srt:GuarantorSubsidiaries, srt:ReportableLegalEntities


Interest
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-30
Value-2.8-2.7-2.7-2.6-2.5-2.5-2.4-2.3
Percentage of InterestExpenseIntercompany100.0100.0100.0100.0100.0100.0100.0100.0

srt:NonGuarantorSubsidiaries, srt:ReportableLegalEntities


Interest
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-30
Value1010111111111111
Percentage of InterestExpenseIntercompany-389.3-400.0-411.1-438.5-448.0-448.0-487.5-491.3

srt:ParentCompany, srt:ReportableLegalEntities


Interest
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-30
Value-8.1-8.1-8.4-8.8-8.7-8.7-9.3-9.0
Percentage of InterestExpenseIntercompany289.3300.0311.1338.5348.0348.0387.5391.3

cenx:LitigationSettlementAmountAwardedtoOtherPartyAnnualPayments us-gaap:BalanceSheetLocation, us-gaap:LossContingenciesByNatureOfContingency

cenx:LitigationSettlementAmountAwardedtoOtherPartyAnnualPayments

us-gaap:OtherCurrentLiabilities, cenx:RavenswoodRetireeMedicalBenefitsChanges


Litigation
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value0.02.00.00.02.00.00.02.00.00.02.0
Percentage of LitigationSettlementAmountAwardedtoOtherPartyAnnualPayments0.0100.00.00.0100.00.00.0100.00.00.0100.0

us-gaap:OtherLiabilities, cenx:RavenswoodRetireeMedicalBenefitsChanges


Litigation
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value0.17.7-1.80.28.9-1.80.310.0-1.70.211
Percentage of LitigationSettlementAmountAwardedtoOtherPartyAnnualPayments0.0385.00.00.0445.00.00.0500.00.00.0555.0

cenx:LitigationSettlementAmountAwardedtoOtherPartyAnnualPayments us-gaap:LossContingenciesByNatureOfContingency

cenx:RavenswoodRetireeMedicalBenefitsChanges


Litigation
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value0.02.00.00.02.00.00.02.00.00.02.0
Percentage of LitigationSettlementAmountAwardedtoOtherPartyAnnualPayments0.0100.00.00.0100.00.00.0100.00.00.0100.0

cenx:NetIncomeLossAvailabletoCommonStockholdersBasicandDiluted

cenx:NetIncomeLossAvailabletoCommonStockholdersBasicandDiluted


Net
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-31
Value-35.5-58.2-26.9-2.7-4.8-20.7-20.7-34.6-65.0-20.317-0.332196.563-15.139-168.464-58.273-9.515-16.163
Percentage of NetIncomeLossAvailabletoCommonStockholdersBasicandDiluted100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cenx:OptionIndexedToIssuersEquityCapPrice us-gaap:DebtInstrument, us-gaap:OptionIndexedToIssuersEquityEquity

cenx:OptionIndexedToIssuersEquityCapPrice

cenx:ConvertibleSeniorNote, us-gaap:CallOption


Option
Period End2021-04-07
Value22.95
Percentage of OptionIndexedToIssuersEquityCapPrice100.0

cenx:OptionIndexedToIssuersEquityIssuanceCost us-gaap:DebtInstrument, us-gaap:OptionIndexedToIssuersEquityEquity

cenx:OptionIndexedToIssuersEquityIssuanceCost

cenx:ConvertibleSeniorNote, us-gaap:CallOption


Option
Period End2021-04-07
Value5700000.0
Percentage of OptionIndexedToIssuersEquityIssuanceCost100.0

cenx:PaymentOfDebtRetirementCostsNet

cenx:PaymentOfDebtRetirementCostsNet


Payment
Period End2020-12-31
Value0
Percentage of PaymentOfDebtRetirementCostsNet0.0

cenx:PaymentOfDebtRetirementCostsNet us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

srt:ParentCompany, srt:ReportableLegalEntities


Payment
Period End2020-12-31
Value0
Percentage of PaymentOfDebtRetirementCostsNet0.0

cenx:PaymentsforProceedsfromIntercompanyTransactionsFinancingActivities us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

cenx:PaymentsforProceedsfromIntercompanyTransactionsFinancingActivities

srt:GuarantorSubsidiaries, srt:ReportableLegalEntities


Paymentsfor
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value-18.9-28.53.0-1.93112-16.9-29.9-31.7-0.129-27.28.6
Percentage of PaymentsforProceedsfromIntercompanyTransactionsFinancingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

srt:NonGuarantorSubsidiaries, srt:ReportableLegalEntities


Paymentsfor
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value105.25.131200.210.014152318-0.431
Percentage of PaymentsforProceedsfromIntercompanyTransactionsFinancingActivities-57.7-18.2170.0-1673.764.61.6-59.2-49.8-47.9-23300.063.11.5364.0

srt:ParentCompany, srt:ReportableLegalEntities


Paymentsfor
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value-13.919-27.2-28.942-17.3-15.9-17.815293.53.836
Percentage of PaymentsforProceedsfromIntercompanyTransactionsFinancingActivities73.5-69.5-906.71521.1134.5-135.294.159.5-47.3-29800.012.1-14.0426.7

cenx:PaymentsforProceedsfromIntercompanyTransactionsFinancingActivities us-gaap:ConsolidationItems

srt:ConsolidationEliminations


Paymentsfor
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value213.519-1.0-95.44.322321.5-53.0-50.823-76.6
Percentage of PaymentsforProceedsfromIntercompanyTransactionsFinancingActivities-115.9-12.3636.752.6-299.133.6-134.9-109.7-4.753000.0-175.2-87.5-890.7

cenx:PaymentsforProceedsfromIntercompanyTransactionsInvestingActivities us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

cenx:PaymentsforProceedsfromIntercompanyTransactionsInvestingActivities

srt:GuarantorSubsidiaries, srt:ReportableLegalEntities


Paymentsfor
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value13-18.02629-42.6191517-13.8-30.7-10.20.0-32.2
Percentage of PaymentsforProceedsfromIntercompanyTransactionsInvestingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0

srt:NonGuarantorSubsidiaries, srt:ReportableLegalEntities


Paymentsfor
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value0.5-2.00.10.1-0.1-1.8-0.1-0.1-2.60.00.40.00.0
Percentage of PaymentsforProceedsfromIntercompanyTransactionsInvestingActivities3.811.10.40.30.2-9.5-0.6-0.618.8-0.0-3.90.0-0.0

srt:ParentCompany, srt:ReportableLegalEntities


Paymentsfor
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value8.423-7.9-30.5-52.7-12.97.01517-22.3-41.023-41.4
Percentage of PaymentsforProceedsfromIntercompanyTransactionsInvestingActivities64.6-130.6-29.4-103.7123.7-67.944.085.9-129.772.6402.00.0128.6

cenx:PaymentsforProceedsfromIntercompanyTransactionsInvestingActivities us-gaap:ConsolidationItems

srt:ConsolidationEliminations


Paymentsfor
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value-21.9-3.5-19.11.095-4.3-22.8-32.8-1.55350-23.873
Percentage of PaymentsforProceedsfromIntercompanyTransactionsInvestingActivities-168.519.4-71.03.4-223.9-22.6-143.4-185.310.9-172.6-498.00.0-228.6

cenx:PensionContributionsAboveRequiredMinimumRemaining us-gaap:CounterpartyName

cenx:PensionContributionsAboveRequiredMinimumRemaining

cenx:PBGCAgreement


Pension
Period End2021-06-302021-03-312020-12-31
Value09600000.00
Percentage of PensionContributionsAboveRequiredMinimumRemaining0.0100.00.0

cenx:RepaymentsofTermLoan

cenx:RepaymentsofTermLoan


Repaymentsof
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-06-302019-03-31
Value5.05.05.05.05.00.00.0
Percentage of RepaymentsofTermLoan100.0100.0100.0100.0100.00.00.0

cenx:WriteOffOfDeferredFinancingCost us-gaap:DebtInstrument, us-gaap:LongtermDebtType, us-gaap:SubsequentEventType

cenx:WriteOffOfDeferredFinancingCost

cenx:SeniorSecuredNotesDueJune012025, us-gaap:LongTermDebt, us-gaap:SubsequentEvent


Write
Period End2021-04-14
Value4400000.0
Percentage of WriteOffOfDeferredFinancingCost100.0

cenx:WriteOffOfDeferredFinancingCost us-gaap:LongtermDebtType

us-gaap:SeniorNotes


Write
Period End2021-04-30
Value4400000.0
Percentage of WriteOffOfDeferredFinancingCost0.0

us-gaap:ConcentrationRiskPercentage1 us-gaap:ConcentrationRiskByBenchmark, us-gaap:ConcentrationRiskByType, us-gaap:RelatedPartyTransactionsByRelatedParty

us-gaap:ConcentrationRiskPercentage1

us-gaap:SalesRevenueNet, us-gaap:CustomerConcentrationRisk, cenx:Glencore


Concentration
Period End2021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-30
Value60.060.00.710.640.6450.6450.640.634
Percentage of ConcentrationRiskPercentage1100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ConcentrationRiskPercentage1 us-gaap:MajorCustomers, us-gaap:ConcentrationRiskByBenchmark, us-gaap:ConcentrationRiskByType

cenx:Glencore, us-gaap:SalesRevenueNet, us-gaap:CustomerConcentrationRisk


Concentration
Period End2021-06-302020-06-30
Value58.071.0
Percentage of ConcentrationRiskPercentage10.010000.0

us-gaap:DebtInstrumentRedemptionPricePercentage us-gaap:DebtInstrument, us-gaap:LongtermDebtType

us-gaap:DebtInstrumentRedemptionPricePercentage

cenx:SeniorSecuredNotes120, us-gaap:SeniorNotes


Debt
Period End2021-05-14
Value107.0
Percentage of DebtInstrumentRedemptionPricePercentage100.0

us-gaap:DefinedBenefitPlanAmortizationOfGainsLosses us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanAmortizationOfGainsLosses

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit


Defined
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value-500000.0-600000.0-600000.0-500000.0-100000.0-1000000.0-600000.0-600000.0-400000.0-800000.01400000.0-1000000.0-3300000.0-1100000.0-2925000.0-958000.01000000.0-900000.0-904000.0-878000.0
Percentage of DefinedBenefitPlanAmortizationOfGainsLosses100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value-1500000.0-1500000.0-1600000.0-1600000.0-1800000.0-1500000.0-1700000.0-1600000.0-2200000.0-1100000.0-1300000.0-1300000.0-1100000.0-1500000.0-820000.0-1187000.0-1500000.0-1200000.0-1541000.0-1041000.0
Percentage of DefinedBenefitPlanAmortizationOfGainsLosses300.0250.0266.7320.01800.0150.0283.3266.7550.0137.5-92.9130.033.3136.428.0123.9-150.0133.3170.5118.6

us-gaap:DefinedBenefitPlanAmortizationOfPriorServiceCostCredit us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanAmortizationOfPriorServiceCostCredit

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit


Defined
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value-800000.0-800000.0-800000.0-800000.0-800000.0-800000.0-600000.0-1200000.0-1800000.0-1300000.0-2200000.0-1800000.0-1500000.0-1800000.0-1961000.0-695000.0-700000.0-300000.0-696000.0-695000.0
Percentage of DefinedBenefitPlanAmortizationOfPriorServiceCostCredit100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value100000.000100000.000-500000.00500000.0000100000.0026000.027000.00022000.028000.0
Percentage of DefinedBenefitPlanAmortizationOfPriorServiceCostCredit-12.5-0.0-0.0-12.5-0.0-0.083.3-0.0-27.8-0.0-0.0-0.0-6.7-0.0-1.3-3.9-0.0-0.0-3.2-4.0

us-gaap:DefinedBenefitPlanExpectedReturnOnPlanAssets us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanExpectedReturnOnPlanAssets

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value5.65.55.25.35.25.14.64.54.34.95.35.35.35.34.3824.755.14.74.3294.813
Percentage of DefinedBenefitPlanExpectedReturnOnPlanAssets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DefinedBenefitPlanInterestCost us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanInterestCost

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit


Defined
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value0.60.60.80.80.70.81.11.11.21.03.81.0-1.81.1-0.4091.3823.01.41.2311.469
Percentage of DefinedBenefitPlanInterestCost100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value2.42.42.92.92.82.83.33.33.43.33.23.13.03.13.3283.3273.33.33.4523.478
Percentage of DefinedBenefitPlanInterestCost400.0400.0362.5362.5400.0350.0300.0300.0283.3330.084.2310.0-166.7281.8-813.7240.7110.0235.7280.4236.8

us-gaap:DefinedBenefitPlanNetPeriodicBenefitCost us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanNetPeriodicBenefitCost

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit


Defined
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value0.30.50.60.50.11.10.50.50.50.50.30.30.00.5-0.6651.8641.52.21.4521.982
Percentage of DefinedBenefitPlanNetPeriodicBenefitCost100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value-0.7-0.20.50.60.50.51.41.42.30.60.30.2-0.10.40.8880.8870.71.01.5271.004
Percentage of DefinedBenefitPlanNetPeriodicBenefitCost-233.3-40.083.3120.0500.045.5280.0280.0460.0120.0100.066.70.080.0-133.547.646.745.5105.250.7

us-gaap:DefinedBenefitPlanServiceCost us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanServiceCost

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit


Defined
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value0100000.000100000.0100000.0-600000.00700000.000100000.00100000.0144000.0219000.0200000.0200000.013000.0330000.0
Percentage of DefinedBenefitPlanServiceCost0.0100.00.00.0100.0100.0100.00.0100.00.00.0100.00.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value900000.01400000.01200000.01300000.01100000.01300000.01500000.01000000.0500000.01100000.01100000.01100000.01000000.01100000.01096000.01096000.01000000.01200000.0841000.01270000.0
Percentage of DefinedBenefitPlanServiceCost0.01400.00.00.01100.01300.0-250.00.071.40.00.01100.00.01100.0761.1500.5500.0600.06469.2384.8

us-gaap:DerivativeGainLossOnDerivativeNet

us-gaap:DerivativeGainLossOnDerivativeNet


Derivative
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value-63.3-98.1-15.4-9.43.73.81.3106.1-5.73.50.81.20.7
Percentage of DerivativeGainLossOnDerivativeNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DerivativeGainLossOnDerivativeNet us-gaap:DerivativeInstrumentRisk

us-gaap:CommodityContract


Derivative
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value-63.6-96.0-17.1-11.02.99.01.7106.1-5.53.61.01.20.7
Percentage of DerivativeGainLossOnDerivativeNet100.597.9111.0117.078.4236.8130.8102.9100.096.5102.9125.0100.0100.0

us-gaap:ForeignExchangeContract


Derivative
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value0.3-2.11.71.60.8-5.2-0.4-0.30.0-0.2-0.1-0.20.00.0
Percentage of DerivativeGainLossOnDerivativeNet-0.52.1-11.0-17.021.6-136.8-30.8-2.90.03.5-2.9-25.00.00.0

us-gaap:DerivativeGainLossOnDerivativeNet us-gaap:DerivativeInstrumentRisk, us-gaap:RelatedPartyTransactionsByRelatedParty

us-gaap:CommodityContract, cenx:Glencore


Derivative
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value-28.7-20.3-9.3-4.6-7.912-0.71.91.8-1.0-2.10.0-0.30.3
Percentage of DerivativeGainLossOnDerivativeNet45.320.760.448.9-213.5331.6-53.818.429.517.5-60.00.0-25.042.9

us-gaap:DerivativeLossOnDerivative us-gaap:DebtInstrument, us-gaap:OptionIndexedToIssuersEquityEquity

us-gaap:DerivativeLossOnDerivative

cenx:ConvertibleSeniorNote, us-gaap:CallOption


Derivative
Period End2021-04-07
Value1000000.0
Percentage of DerivativeLossOnDerivative100.0

us-gaap:DerivativeNonmonetaryNotionalAmountMass us-gaap:DerivativeInstrumentRisk

us-gaap:DerivativeNonmonetaryNotionalAmountMass

cenx:FixedtoFloatingSwap


Derivative
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-31
Value-2525.016482.0-3450.0-1452.0-675.015271.0-1304.0-1996.012093.0
Percentage of DerivativeNonmonetaryNotionalAmountMass100.0100.0100.0100.0100.0100.0100.0100.0100.0

cenx:MidwestPremiumMWP


Derivative
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value-28500.0418500.0192000.0-25500.034500.0117000.010750.016750.018250.0104250.0
Percentage of DerivativeNonmonetaryNotionalAmountMass1128.72539.1-5565.21756.2-5111.1766.20.0-1284.5-914.3862.1

us-gaap:FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisUnobservableInputsReconciliationGainLossIncludedInEarnings us-gaap:DerivativeInstrumentRisk

us-gaap:FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisUnobservableInputsReconciliationGainLossIncludedInEarnings

cenx:FXSwap


Fair
Period End2021-06-302019-12-312019-09-302019-06-302019-03-31
Value0.00.10.00.0-0.3
Percentage of FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisUnobservableInputsReconciliationGainLossIncludedInEarnings0.0100.00.00.0100.0

cenx:FixedtoVariableLondonMetalsExchangeSwap


Fair
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-31
Value-11.6-8.7-2.3-4.2-1.76.7
Percentage of FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisUnobservableInputsReconciliationGainLossIncludedInEarnings0.00.00.00.00.00.0

cenx:HawesvilleL4PowerPriceSwaps


Fair
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-30
Value1.7-0.20.0-1.5-1.51.20.0
Percentage of FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisUnobservableInputsReconciliationGainLossIncludedInEarnings0.00.00.00.0-1500.00.00.0

us-gaap:FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisUnobservableInputsReconciliationSettlements us-gaap:DerivativeInstrumentRisk

us-gaap:FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisUnobservableInputsReconciliationSettlements

cenx:HawesvilleL4PowerPriceSwaps


Fair
Period End2020-12-312020-09-302020-06-302020-03-312019-06-30
Value-900000.0900000.01700000.01200000.00
Percentage of FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisUnobservableInputsReconciliationSettlements100.0100.0100.0100.00.0

us-gaap:FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisUnobservableInputsReconciliationTransfersIntoLevel3 us-gaap:DerivativeInstrumentRisk

us-gaap:FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisUnobservableInputsReconciliationTransfersIntoLevel3

cenx:FXSwap


Fair
Period End2021-06-302021-03-312019-06-302019-03-31
Value-200000.0-200000.000
Percentage of FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisUnobservableInputsReconciliationTransfersIntoLevel3100.0100.00.00.0

cenx:FixedtoVariableLondonMetalsExchangeSwap


Fair
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-31
Value-300000.0-700000.01800000.04700000.000
Percentage of FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisUnobservableInputsReconciliationTransfersIntoLevel3150.0350.00.00.00.00.0

cenx:NordpoolPowerPriceSwap


Fair
Period End2021-06-302019-06-302019-03-31
Value1500000.000
Percentage of FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisUnobservableInputsReconciliationTransfersIntoLevel3-750.00.00.0

us-gaap:FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisUnobservableInputsReconciliationTransfersOutOfLevel3 us-gaap:DerivativeInstrumentRisk

us-gaap:FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisUnobservableInputsReconciliationTransfersOutOfLevel3

cenx:FXSwap


Fair
Period End2021-06-302021-03-312019-12-312019-09-302019-06-302019-03-31
Value200000.0-100000.0-100000.00600000.00
Percentage of FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisUnobservableInputsReconciliationTransfersOutOfLevel3100.0100.0100.00.0100.00.0

cenx:FixedtoVariableLondonMetalsExchangeSwap


Fair
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-31
Value-1000000.0500000.0-3200000.000-9500000.0
Percentage of FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisUnobservableInputsReconciliationTransfersOutOfLevel3-500.0-500.00.00.00.00.0

us-gaap:ForeignCurrencyCashFlowHedgeGainLossReclassifiedToEarningsNet

us-gaap:ForeignCurrencyCashFlowHedgeGainLossReclassifiedToEarningsNet


Foreign
Period End2021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value0-100000.0-100000.000-100000.00000000-46000.0-46000.0-48000.0-46000.04434000.0-46000.0-47000.0-46000.0-47000.0-46000.0-46000.0-47000.0-47000.0-46000.0-47000.0-47000.0-47000.0-46000.0-46000.0-47000.0-46000.0-47000.0-46000.047000.0-47000.0-47000.0-47000.046000.0
Percentage of ForeignCurrencyCashFlowHedgeGainLossReclassifiedToEarningsNet0.0100.0100.00.00.0100.00.00.00.00.00.00.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:GainLossOnDerivativeInstrumentsNetPretax

us-gaap:GainLossOnDerivativeInstrumentsNetPretax


Gain
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value-64.4-98.1-15.4-9.43.73.81.3106.1-5.73.50.81.20.70.519-3.8882.957-16.1370.4891.2750.3530.3530.3960.2850.5660.3530.3530.3530.352-0.8790.4470.440.20415-0.101-0.341.45-5.1593.0674.163-1.617-4.809-5.681-12.1369.294-1.972
Percentage of GainLossOnDerivativeInstrumentsNetPretax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:GainLossOnDerivativeInstrumentsNetPretax us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

srt:GuarantorSubsidiaries, srt:ReportableLegalEntities


Gain
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value0.30.40.30.40.40.30.30.40.30.40.40.30.1-3.9
Percentage of GainLossOnDerivativeInstrumentsNetPretax-1.9-4.38.110.530.82.94.9-7.08.650.033.342.919.3100.3

srt:NonGuarantorSubsidiaries, srt:ReportableLegalEntities


Gain
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value-5.60.25.3-29.2-0.8-0.21.0-1.41.70.60.80.40.50.0
Percentage of GainLossOnDerivativeInstrumentsNetPretax36.4-2.1143.2-768.4-61.5-1.916.424.648.675.066.757.196.3-0.0

srt:ParentCompany, srt:ReportableLegalEntities


Gain
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value-10.1-10.0-1.9321.7104.8-4.71.5-0.20.00.00.00.0
Percentage of GainLossOnDerivativeInstrumentsNetPretax65.6106.4-51.4857.9130.899.078.782.542.9-25.00.00.00.0-0.0

us-gaap:IncomeLossAttributableToParent

us-gaap:IncomeLossAttributableToParent


Income
Period End2021-06-302021-03-312020-06-302020-03-31
Value-83400000.0-142300000.0-26000000.0-5500000.0
Percentage of IncomeLossAttributableToParent100.0100.0100.0100.0

us-gaap:IncreaseDecreaseInAccountsPayableTrade

us-gaap:IncreaseDecreaseInAccountsPayableTrade


Increase
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value14-4.932-2.01.3-11.3-13.911-12.9-10.27.1-4.6225.40.1755.5183.43-4.3777.299-4.0094.964-5.983-17.098-9.398-15.579-18.50820-0.472-4.588-3.825-1.323-4.149282.264-3.2917.108-4.489-11.4421.879-1.5813.528-4.73125.419-4.502-2.223
Percentage of IncreaseDecreaseInAccountsPayableTrade100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncreaseDecreaseInAccruedLiabilities

us-gaap:IncreaseDecreaseInAccruedLiabilities


Increase
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value-5.13.8-7.96.65.7-5.6-5.710.02.2-3.8-12.8-0.5-4.06.25.226130.458-4.905-8.6695.254-1.7381.253-23.122-9.706-1.5862.874254.634-5.58-6.623.6254.036-9.3657.538-14.4896.993-5.2537.003-16.6469.4964.173.405-4.5765.007-3.6121.423
Percentage of IncreaseDecreaseInAccruedLiabilities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncreaseDecreaseInDueFromRelatedPartiesCurrent

us-gaap:IncreaseDecreaseInDueFromRelatedPartiesCurrent


Increase
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value4.40000000000000212-5.96.7-1.4-20.26.91.8-2.71.12.313-2.1-1.7-1.4831.354-1.294-4.8622.38-0.24-0.967-1.939-11.68-23.213-32.75253-20.95-1.642-2.0371218-0.009-18.5975.691-1.8855.084-5.650.249-4.0924.663-2.499-8.766
Percentage of IncreaseDecreaseInDueFromRelatedPartiesCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncreaseDecreaseInDueToRelatedPartiesCurrent

us-gaap:IncreaseDecreaseInDueToRelatedPartiesCurrent


Increase
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value2.87.07.51.1-27.8-3.232-13.210-7.2-6.314-12.1-6.03.31-2.0810.3083.2962.5843.0686.932-5.372-23.611-30.0111327-8.27812-22.02420-18.1574.3951710-2.928-0.391.511-0.36-3.0015.358-3.112-2.722
Percentage of IncreaseDecreaseInDueToRelatedPartiesCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets

us-gaap:IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets


Increase
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value1.23.1-1.6-0.11.2-0.11.1-1.70.5-2.62.7-2.71.7-0.8-6.6882.7260.892-4.726-9.2973.51.774-14.293.5790.3842.141-5.96-0.3573.781-9.7742.958-10.21-1.1-0.086.072-13.24.377-1.4895.366463.5860.91-29.901-29.968-3.867163.692
Percentage of IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:InterestExpenseRelatedParty

us-gaap:InterestExpenseRelatedParty


Interest
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value0.20.30.30.40.50.70.80.80.60.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0
Percentage of InterestExpenseRelatedParty100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:InterestExpenseRelatedParty us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

srt:ParentCompany, srt:ReportableLegalEntities


Interest
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-03-312017-12-312017-09-30
Value0.30.40.50.70.80.80.6-8.7-8.9-9.3-9.0-10.2-8.9
Percentage of InterestExpenseRelatedParty100.0100.0100.0100.0100.0100.0100.00.00.00.00.00.00.0

us-gaap:InterestIncomeOther

us-gaap:InterestIncomeOther


Interest
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-30
Value100000.0100000.0200000.0100000.0400000.0100000.0200000.0200000.0200000.0200000.0200000.0400000.0500000.0500000.0462000.0422000.0283000.0230000.0283000.0190000.0171000.0114000.091000.045000.061000.0142000.0104000.023000.034000.0140000.0270000.0141000.0186000.0131000.0168000.072000.0
Percentage of InterestIncomeOther100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:InterestIncomeOther us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

srt:NonGuarantorSubsidiaries, srt:ReportableLegalEntities


Interest
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value100000.0100000.0100000.0100000.0200000.0100000.0100000.0200000.0200000.0300000.0400000.0300000.0300000.0200000.0
Percentage of InterestIncomeOther50.0100.025.0100.0100.050.050.0100.0100.075.080.060.064.947.4

srt:ParentCompany, srt:ReportableLegalEntities


Interest
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value100000.00300000.000100000.0100000.000100000.0100000.0200000.0200000.0200000.0
Percentage of InterestIncomeOther50.00.075.00.00.050.050.00.00.025.020.040.043.347.4

us-gaap:InventoryWriteDown

us-gaap:InventoryWriteDown


Inventory
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value4.23.723133.02.4130.0309.10.0-3.23.0290.0-0.222-3.88-2.1592.374.913-5.784235.324250.00.00.0-0.14-1.107-9.039-5.763105.8380.0-8.2015.434-17.0516.303130.123-0.139-0.125-7.37.056-0.057
Percentage of InventoryWriteDown100.0100.0100.0100.0100.0100.0100.00.0100.0100.00.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.00.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:LitigationSettlementAmountAwardedToOtherParty us-gaap:StatementGeographical, us-gaap:LossContingenciesByNatureOfContingency

us-gaap:LitigationSettlementAmountAwardedToOtherParty

cenx:StCroix, cenx:HydrocarbonRecoveryPlan


Litigation
Period End2021-06-30
Value0.6
Percentage of LitigationSettlementAmountAwardedToOtherParty100.0

us-gaap:OptionIndexedToIssuersEquityStrikePrice1 us-gaap:DebtInstrument, us-gaap:OptionIndexedToIssuersEquityEquity

us-gaap:OptionIndexedToIssuersEquityStrikePrice1

cenx:ConvertibleSeniorNote, us-gaap:CallOption


Option
Period End2021-04-07
Value18.74
Percentage of OptionIndexedToIssuersEquityStrikePrice1100.0

us-gaap:OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditBeforeTax

us-gaap:OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditBeforeTax


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-30
Value-800000.0-800000.0-700000.0-700000.0-800000.0-800000.0-1000000.0-1200000.0-1300000.0-1300000.0-2100000.0-1800000.0-1400000.0-1800000.0-3298000.0-670000.0-671000.0-311000.0-674000.0-667000.0-667000.0-667000.0-5505000.0-979000.0-931000.0-936000.0-648000.0-952000.0-952000.0-952000.0-1008000.0-968000.0-916000.0-1028000.0-1028000.0-1029000.0
Percentage of OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditBeforeTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherComprehensiveIncomeLossBeforeTax

us-gaap:OtherComprehensiveIncomeLossBeforeTax


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-30
Value1.21.3-12.01.31.01.7-11.61.01.20.6-9.70.53.00.8201.429-0.1421.786-3.331.2061.2061.206-10.396-3.241190.461-38.3240.4040.4360.812470.866111.277-19.8821.5562.1481.138-56.2730.716
Percentage of OtherComprehensiveIncomeLossBeforeTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherComprehensiveIncomeLossBeforeTax us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

srt:GuarantorSubsidiaries, srt:ReportableLegalEntities


Other
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value-7.00.80.41.1-4.80.80.30.6-28.10.52.80.7111.0
Percentage of OtherComprehensiveIncomeLossBeforeTax58.361.540.064.741.480.025.0100.0289.7100.093.387.557.870.0

srt:NonGuarantorSubsidiaries, srt:ReportableLegalEntities


Other
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value-2.60.40.50.4-3.20.51.20.34.00.40.30.40.30.3
Percentage of OtherComprehensiveIncomeLossBeforeTax21.730.850.023.527.650.0100.050.0-41.280.010.050.01.521.0

srt:ParentCompany, srt:ReportableLegalEntities


Other
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value-12.01.31.01.7-11.61.01.20.6-9.70.53.00.8201.4
Percentage of OtherComprehensiveIncomeLossBeforeTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.098.0

us-gaap:OtherComprehensiveIncomeLossBeforeTax us-gaap:ConsolidationItems

srt:ConsolidationEliminations


Other
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value9.6-1.2-0.9-1.58.0-1.3-1.5-0.924-0.9-3.1-1.1-12.2-1.3
Percentage of OtherComprehensiveIncomeLossBeforeTax-80.0-92.3-90.0-88.2-69.0-130.0-125.0-150.0-248.5-180.0-103.3-137.5-59.2-91.0

us-gaap:OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax

us-gaap:OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax


Other
Period End2021-06-302020-06-30
Value100000.00
Percentage of OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax100.00.0

us-gaap:OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent

us-gaap:OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent


Other
Period End2021-06-302020-06-30
Value1.10.7
Percentage of OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent100.0100.0

us-gaap:OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent us-gaap:StatementEquityComponents

us-gaap:AccumulatedOtherComprehensiveIncome


Other
Period End2021-06-302020-06-30
Value1.10.7
Percentage of OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent100.0100.0

us-gaap:OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossBeforeTax

us-gaap:OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossBeforeTax


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-30
Value-2100000.0-2100000.0-2200000.0-2100000.0-1800000.0-2500000.0-2200000.0-2200000.0-2500000.0-1900000.0200000.0-2300000.0-4400000.0-2600000.0-3745000.0-2145000.0-577000.0-2143000.0-2432000.0-1919000.0-1920000.0-1919000.0-1772000.0-1899000.0-2679000.0-1444000.0-6105000.0-1402000.0-995000.0-1811000.0-1812000.0-1880000.0-2130000.0-2352000.0-2150000.0-2562000.0
Percentage of OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossBeforeTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherComprehensiveIncomeLossTax

us-gaap:OtherComprehensiveIncomeLossTax


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value100000.00200000.0200000.0300000.0300000.0200000.0300000.0200000.0300000.0400000.0400000.0400000.0400000.0382000.0382000.0-311000.01074000.0384000.0382000.0382000.0383000.0388000.0383000.0382000.0383000.0-8000.0557000.0567000.0713000.0416000.0383000.0383000.0382000.0417000.0382000.0-383000.0382000.0-11128000.0383000.0-2513000.02460000.0
Percentage of OtherComprehensiveIncomeLossTax100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherComprehensiveIncomeLossTax us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

srt:ParentCompany, srt:ReportableLegalEntities


Other
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value200000.0200000.0300000.0300000.0200000.0300000.0200000.0300000.0400000.0400000.0400000.0400000.0300000.0400000.0
Percentage of OtherComprehensiveIncomeLossTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.078.5104.7

us-gaap:OtherOperatingActivitiesCashFlowStatement

us-gaap:OtherOperatingActivitiesCashFlowStatement


Other
Period End2021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value3200000.0-2400000.0-400000.02600000.0-700000.00-800000.0-600000.0-4500000.0-9200000.04200000.0-3600000.0-4600000.0-3792000.03100000.0-1300000.01200000.0
Percentage of OtherOperatingActivitiesCashFlowStatement100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherOperatingIncome

us-gaap:OtherOperatingIncome


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302012-03-312011-06-302011-03-31
Value221175156157116150142155168178166176187158111101-3.7215.2055.884
Percentage of OtherOperatingIncome100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherOperatingIncome us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

srt:GuarantorSubsidiaries, srt:ReportableLegalEntities


Other
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value13212591126134144162172165175185157111101
Percentage of OtherOperatingIncome85.280.078.784.194.092.696.596.699.699.699.299.599.9100.0

srt:NonGuarantorSubsidiaries, srt:ReportableLegalEntities


Other
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value233124238.5115.96.00.70.71.50.80.10.0
Percentage of OtherOperatingIncome14.820.021.315.96.07.43.53.40.40.40.80.50.10.0

us-gaap:OtherOperatingIncomeExpenseNet

us-gaap:OtherOperatingIncomeExpenseNet


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-30
Value-0.1-0.1-0.20.2-0.2-0.3-0.40.1-0.3-0.3-0.40.5-0.2-0.3-0.521-0.437-0.18-0.973-1.52-0.878-0.578-0.881-1.219-1.537-2.601-2.079-6.776-1.417-1.874-2.414-2.314-2.174-3.018-1.096-3.327-7.388-3.817-3.721-4.624-2.659
Percentage of OtherOperatingIncomeExpenseNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherOperatingIncomeExpenseNet us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

srt:NonGuarantorSubsidiaries, srt:ReportableLegalEntities


Other
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value-0.20.2-0.2-0.3-0.40.1-0.3-0.3-0.40.5-0.2-0.3-0.5-0.4
Percentage of OtherOperatingIncomeExpenseNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.096.091.5

us-gaap:OtherOperatingIncomeExpenseNet us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:StatementEquityComponents

us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:AccumulatedDefinedBenefitPlansAdjustment


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-31
Value-0.4-0.40.3-0.5-0.5-0.41.1-0.5-1.2-0.4-0.10.40.4-0.52.321-0.3830.5280.3940.5350.350.350.350.9040.00.00.0
Percentage of OtherOperatingIncomeExpenseNet400.0400.0-150.0-250.0250.0133.3-275.0-500.0400.0133.325.080.0-200.0166.7-445.587.6-293.3-40.5-35.2-39.9-60.6-39.7-74.2-0.0-0.0-0.0

us-gaap:PaymentsOfDebtIssuanceCosts

us-gaap:PaymentsOfDebtIssuanceCosts


Payments
Period End2020-12-312014-12-312014-09-302013-12-312013-09-302012-12-312012-09-30
Value000068000.000
Percentage of PaymentsOfDebtIssuanceCosts0.00.00.00.0100.00.00.0

us-gaap:PaymentsOfDebtIssuanceCosts us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

srt:ParentCompany, srt:ReportableLegalEntities


Payments
Period End2020-12-31
Value0
Percentage of PaymentsOfDebtIssuanceCosts0.0

us-gaap:ProceedsFromConvertibleDebt us-gaap:DebtInstrument, us-gaap:LongtermDebtType

us-gaap:ProceedsFromConvertibleDebt

cenx:ConvertibleSeniorNote, us-gaap:SeniorNotes


Proceeds
Period End2021-04-09
Value83
Percentage of ProceedsFromConvertibleDebt100.0

us-gaap:ProceedsFromIssuanceOfDebt

us-gaap:ProceedsFromIssuanceOfDebt


Proceeds
Period End2020-12-31
Value0.0
Percentage of ProceedsFromIssuanceOfDebt0.0

us-gaap:ProceedsFromIssuanceOfDebt us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

srt:ParentCompany, srt:ReportableLegalEntities


Proceeds
Period End2020-12-31
Value0.0
Percentage of ProceedsFromIssuanceOfDebt0.0

us-gaap:ProceedsFromIssuanceOfDebt us-gaap:DebtInstrument

cenx:SeniorSecuredNotesDueJune012025


Proceeds
Period End2020-07-01
Value243
Percentage of ProceedsFromIssuanceOfDebt0.0

us-gaap:ProceedsFromIssuanceOfSeniorLongTermDebt us-gaap:DebtInstrument, us-gaap:LongtermDebtType

us-gaap:ProceedsFromIssuanceOfSeniorLongTermDebt

cenx:SeniorSecuredNotes75, us-gaap:SeniorNotes


Proceeds
Period End2021-04-14
Value245
Percentage of ProceedsFromIssuanceOfSeniorLongTermDebt100.0

us-gaap:ProceedsFromLinesOfCredit

us-gaap:ProceedsFromLinesOfCredit


Proceeds
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-30
Value22919785510.6121732611816910514-0.30.30.2590.3020.4870.2330.2790.3050.2240.3710.3230.4040.5550.4550.6925.08567186.0160.00.00.00.00.0180.015
Percentage of ProceedsFromLinesOfCredit100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.00.00.00.0100.00.0100.0

us-gaap:ProceedsFromLinesOfCredit us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

srt:NonGuarantorSubsidiaries, srt:ReportableLegalEntities


Proceeds
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-03-312017-12-31
Value0.00.00.0450.0190.00.00.00.00.0
Percentage of ProceedsFromLinesOfCredit0.00.00.036.90.073.90.00.00.00.00.0

srt:ParentCompany, srt:ReportableLegalEntities


Proceeds
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-03-312017-12-31
Value85510.676736.91181691050.30.3
Percentage of ProceedsFromLinesOfCredit100.0100.0100.063.1100.026.1100.0100.0100.0100.0115.8

us-gaap:ProceedsFromSaleOfPropertyPlantAndEquipment

us-gaap:ProceedsFromSaleOfPropertyPlantAndEquipment


Proceeds
Period End2020-12-312020-09-302020-06-302020-03-312019-06-302019-03-312018-12-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-30
Value1.50.00.00.10.00.00.10.0320.8670.0131.040.00.00.00.00.00.00.00.0460.00.010.00.1620.3530.0990.0210.010.0580.01.4150.0560.00.0150.808
Percentage of ProceedsFromSaleOfPropertyPlantAndEquipment100.00.00.0100.00.00.0100.0100.0100.00.0100.0100.00.00.00.00.00.00.00.0100.00.0100.00.0100.0100.0100.0100.0100.0100.00.0100.0100.00.0100.0100.0

us-gaap:ProceedsFromSaleOfPropertyPlantAndEquipment us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

srt:NonGuarantorSubsidiaries, srt:ReportableLegalEntities


Proceeds
Period End2020-12-312020-09-302017-12-31
Value0.00.0-0.1
Percentage of ProceedsFromSaleOfPropertyPlantAndEquipment0.00.0-312.5

us-gaap:ReclassificationFromAociCurrentPeriodNetOfTaxAttributableToParent

us-gaap:ReclassificationFromAociCurrentPeriodNetOfTaxAttributableToParent


Reclassification
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-03-312018-03-31
Value-1100000.0-1300000.0-1200000.0-1100000.0-800000.0-1400000.0-900000.0-700000.0-300000.0-400000.0
Percentage of ReclassificationFromAociCurrentPeriodNetOfTaxAttributableToParent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ReclassificationFromAociCurrentPeriodNetOfTaxAttributableToParent us-gaap:StatementEquityComponents

us-gaap:AccumulatedDefinedBenefitPlansAdjustment


Reclassification
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value-1200000.0-1300000.0-1200000.0-1200000.0-800000.0-1400000.0-900000.0-700000.0-1000000.0-300000.02800000.0-100000.0-2600000.0-400000.0
Percentage of ReclassificationFromAociCurrentPeriodNetOfTaxAttributableToParent109.1100.0100.0109.1100.0100.0100.0100.00.0100.00.00.00.0100.0

us-gaap:AccumulatedGainLossNetCashFlowHedgeParent


Reclassification
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value100000.000100000.00000000000
Percentage of ReclassificationFromAociCurrentPeriodNetOfTaxAttributableToParent-9.1-0.0-0.0-9.1-0.0-0.0-0.0-0.00.0-0.00.00.00.0-0.0

us-gaap:RedemptionPremium us-gaap:LongtermDebtType

us-gaap:RedemptionPremium

us-gaap:SeniorNotes


Redemption
Period End2021-04-30
Value18
Percentage of RedemptionPremium100.0

us-gaap:RelatedPartyCosts us-gaap:MajorCustomers

us-gaap:RelatedPartyCosts

cenx:Glencore


Related
Period End2021-06-302020-06-30
Value7933
Percentage of RelatedPartyCosts100.0100.0

us-gaap:RelatedPartyCosts us-gaap:RelatedPartyTransactionsByRelatedParty

cenx:Glencore


Related
Period End2021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-31
Value726063334074431159011457100485781417175625044658613310791696063
Percentage of RelatedPartyCosts0.00.00.0100.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:RepaymentsOfLinesOfCredit

us-gaap:RepaymentsOfLinesOfCredit


Repayments
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
Value24019290910.6356934145157960.0-0.30.30.2590.3020.4870.2330.2790.3050.2240.3710.3230.4040.5550.4550.6925.0856724160.00.00.00.00.00.01831-15.90.00.00.0
Percentage of RepaymentsOfLinesOfCredit100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.00.00.00.00.0100.0100.0100.00.00.00.0

us-gaap:RepaymentsOfLinesOfCredit us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

srt:ParentCompany, srt:ReportableLegalEntities


Repayments
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-03-312017-12-31
Value90910.63569141451570.30.3
Percentage of RepaymentsOfLinesOfCredit100.0100.0100.0100.0100.043.0100.0100.0100.0115.8

us-gaap:RevenueFromRelatedParties

us-gaap:RevenueFromRelatedParties


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value30626823323528527129228230531132030528229632129929628030630129028035042851357536332428828513812811013214013413913712414315913811110410492
Percentage of RevenueFromRelatedParties100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:RevenueFromRelatedParties us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

srt:GuarantorSubsidiaries, srt:ReportableLegalEntities


Revenue
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value11011615614713313214715213811093110143138
Percentage of RevenueFromRelatedParties47.449.454.754.645.647.148.349.043.236.333.137.444.546.2

srt:NonGuarantorSubsidiaries, srt:ReportableLegalEntities


Revenue
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value122119129123159149157158181194189185178161
Percentage of RevenueFromRelatedParties52.650.645.345.454.452.951.751.056.863.766.962.655.553.8

us-gaap:RevenueFromRelatedParties us-gaap:MajorCustomers

cenx:Glencore


Revenue
Period End2021-06-302020-06-30
Value306285
Percentage of RevenueFromRelatedParties100.0100.0

us-gaap:RevenueFromRelatedParties us-gaap:MajorCustomers, us-gaap:ProductOrService

cenx:Glencore, cenx:Alumina


Revenue
Period End2021-06-302020-06-30
Value110.9
Percentage of RevenueFromRelatedParties3.70.3

us-gaap:RevenueFromRelatedParties us-gaap:ProductOrService, us-gaap:RelatedPartyTransactionsByRelatedParty

cenx:Aluminum, cenx:Glencore


Revenue
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-31
Value160.90.34.5138.2
Percentage of RevenueFromRelatedParties7.00.30.11.64.52.6

us-gaap:RevenueFromRelatedParties us-gaap:RelatedPartyTransactionsByRelatedParty

cenx:Glencore


Revenue
Period End2021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-31
Value268233235285271292282305311320305282296321299296280306301290280350428513575363324288285
Percentage of RevenueFromRelatedParties100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:UnrealizedGainLossOnDerivatives

us-gaap:UnrealizedGainLossOnDerivatives


Unrealized
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value-33.1-94.4-13.4-5.9-0.13.70.5106.4-5.64.60.70.80.4
Percentage of UnrealizedGainLossOnDerivatives100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cenx:AccruedLiabilitiesCurrentandOther

cenx:AccruedLiabilitiesCurrentandOther


Accrued
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312018-12-31
Value596976506552
Percentage of AccruedLiabilitiesCurrentandOther100.0100.0100.0100.0100.0100.0

cenx:AccruedLiabilitiesCurrentandOther us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

srt:GuarantorSubsidiaries, srt:ReportableLegalEntities


Accrued
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312018-12-31
Value232222182722
Percentage of AccruedLiabilitiesCurrentandOther39.932.129.436.441.743.4

srt:NonGuarantorSubsidiaries, srt:ReportableLegalEntities


Accrued
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312018-12-31
Value182328151413
Percentage of AccruedLiabilitiesCurrentandOther30.333.736.529.822.426.5

srt:ParentCompany, srt:ReportableLegalEntities


Accrued
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312018-12-31
Value172326172315
Percentage of AccruedLiabilitiesCurrentandOther29.834.234.133.835.930.1

cenx:AccumulatedOtherComprehensiveIncomeTaxEffect

cenx:AccumulatedOtherComprehensiveIncomeTaxEffect


Accumulated
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312010-12-31
Value-2600000.0-2700000.0-2800000.0-3000000.0-3300000.0-3500000.0-3800000.0-4000000.0-4300000.0-4600000.0-6100000.06500000.06900000.0-7300000.0-7638000.0-8020000.0-8402000.0-8090000.0-9164000.0-9548000.0-9930000.0-10312000.0-10695000.0-11083000.0-11466000.0-11848000.0-12231000.0-12222000.0-12779000.0-13346000.0-14059000.0-14475000.0-14858000.0-15241000.0-15623000.0-16040000.0-16422000.0-16805000.0-17187000.0-22958000.0
Percentage of AccumulatedOtherComprehensiveIncomeTaxEffect100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cenx:AccumulatedOtherComprehensiveIncomeTaxEffect us-gaap:StatementEquityComponents

us-gaap:AccumulatedDefinedBenefitPlansAdjustment


Accumulated
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302012-12-31
Value-3000000.0-3100000.0-3200000.03400000.03700000.04000000.0-4300000.04500000.04800000.05100000.0-6600000.07000000.07400000.0-7800000.0-8173000.0-8564000.0-8955000.0-8654000.0-9736000.0-10071000.0-10461000.0-10852000.0-11243000.0-11639000.0-12031000.0-12421000.0-12812000.0-12445000.0-12993000.0-13552000.0-14256000.0-14663000.0-15784000.0
Percentage of AccumulatedOtherComprehensiveIncomeTaxEffect115.4114.8114.3-113.3-112.1-114.3113.2-112.5-111.6-110.9108.2107.7107.2106.8107.0106.8106.6107.0106.2105.5105.3105.2105.1105.0104.9104.8104.8101.8101.7101.5101.4101.3101.0

us-gaap:AccumulatedGainLossNetCashFlowHedgeParent


Accumulated
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value400000.0400000.0400000.0-400000.0-400000.0-500000.0400000.0-500000.0-500000.0-500000.0-500000.0
Percentage of AccumulatedOtherComprehensiveIncomeTaxEffect-15.4-14.8-14.313.312.114.3-10.512.511.610.98.2

cenx:ContingentObligationAccruedInterest us-gaap:BalanceSheetLocation, us-gaap:DebtInstrument

cenx:ContingentObligationAccruedInterest

us-gaap:OtherLiabilities, cenx:EOnContingentObligation


Contingent
Period End2020-12-312019-12-312018-12-312017-12-312016-12-31
Value1312109.5248.113
Percentage of ContingentObligationAccruedInterest100.0100.0100.0100.0100.0

cenx:ContingentObligationDerivativeAsset us-gaap:BalanceSheetLocation, us-gaap:DebtInstrument

cenx:ContingentObligationDerivativeAsset

us-gaap:OtherLiabilities, cenx:EOnContingentObligation


Contingent
Period End2020-12-312019-12-312018-12-312017-12-312016-12-31
Value2625232221
Percentage of ContingentObligationDerivativeAsset100.0100.0100.0100.0100.0

cenx:ContingentObligationPrincipal us-gaap:BalanceSheetLocation, us-gaap:DebtInstrument

cenx:ContingentObligationPrincipal

us-gaap:OtherLiabilities, cenx:EOnContingentObligation


Contingent
Period End2020-12-312019-12-312018-12-312017-12-312016-12-31
Value1212121212
Percentage of ContingentObligationPrincipal100.0100.0100.0100.0100.0

cenx:DebtDomestic

cenx:DebtDomestic


Debt
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-12-31
Value39505.045454.0
Percentage of DebtDomestic100.0100.0100.0100.0100.0100.0

cenx:DebtDomestic us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

srt:ParentCompany, srt:ReportableLegalEntities


Debt
Period End2020-09-302020-06-302020-03-31
Value5.04545
Percentage of DebtDomestic100.0100.0100.0

cenx:DebtForeign

cenx:DebtForeign


Debt
Period End2020-12-312020-09-302020-06-302020-03-312019-12-31
Value454545450.0
Percentage of DebtForeign100.0100.0100.0100.00.0

cenx:DebtForeignNoncurrent

cenx:DebtForeignNoncurrent


Debt
Period End2020-12-31
Value45
Percentage of DebtForeignNoncurrent100.0

cenx:DebtForeignNoncurrent us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

srt:NonGuarantorSubsidiaries, srt:ReportableLegalEntities


Debt
Period End2020-12-31
Value45
Percentage of DebtForeignNoncurrent100.0

cenx:DebtInstrumentInterestRateStatedPercentageAdditionalNotesOrCash us-gaap:DebtInstrument, us-gaap:LongtermDebtType

cenx:DebtInstrumentInterestRateStatedPercentageAdditionalNotesOrCash

cenx:SeniorSecuredNotesDueJune012025, us-gaap:LongTermDebt


Debt
Period End2020-07-01
Value2.0
Percentage of DebtInstrumentInterestRateStatedPercentageAdditionalNotesOrCash100.0

cenx:DebtInstrumentInterestRateStatedPercentageAdditionalNotesOrCash us-gaap:DebtInstrument, us-gaap:LongtermDebtType, us-gaap:SubsequentEventType

cenx:SeniorSecuredNotesDue2025, us-gaap:LongTermDebt, us-gaap:SubsequentEvent


Debt
Period End2020-07-01
Value0.02
Percentage of DebtInstrumentInterestRateStatedPercentageAdditionalNotesOrCash1.0

cenx:DebtInstrumentInterestRateStatedPercentageCash us-gaap:DebtInstrument, us-gaap:LongtermDebtType

cenx:DebtInstrumentInterestRateStatedPercentageCash

cenx:SeniorSecuredNotesDueJune012025, us-gaap:LongTermDebt


Debt
Period End2020-07-01
Value10.0
Percentage of DebtInstrumentInterestRateStatedPercentageCash100.0

cenx:DebtInstrumentInterestRateStatedPercentageCash us-gaap:DebtInstrument, us-gaap:LongtermDebtType, us-gaap:SubsequentEventType

cenx:SeniorSecuredNotesDue2025, us-gaap:LongTermDebt, us-gaap:SubsequentEvent


Debt
Period End2020-07-01
Value0.1
Percentage of DebtInstrumentInterestRateStatedPercentageCash1.0

cenx:DebtInstrumentPrincipalPayment us-gaap:DebtInstrument

cenx:DebtInstrumentPrincipalPayment

us-gaap:RevolvingCreditFacility


Debt
Period End2021-06-30
Value30
Percentage of DebtInstrumentPrincipalPayment100.0

cenx:DebtInstrumentPrincipalPayment us-gaap:DebtInstrument, us-gaap:ShortTermDebtType

us-gaap:RevolvingCreditFacility, us-gaap:ShortTermDebt


Debt
Period End2021-03-312020-12-312020-09-30
Value252015
Percentage of DebtInstrumentPrincipalPayment0.00.00.0

cenx:DebtInstrumentTenderPremium us-gaap:DebtInstrument

cenx:DebtInstrumentTenderPremium

cenx:SeniorSecuredNotesDueJune012025


Debt
Period End2021-03-31
Value14
Percentage of DebtInstrumentTenderPremium100.0

cenx:DebtInstrumentTenderPremium us-gaap:DebtInstrument, us-gaap:LongtermDebtType, us-gaap:SubsequentEventType

cenx:SeniorSecuredNotesDueJune012025, us-gaap:LongTermDebt, us-gaap:SubsequentEvent


Debt
Period End2021-04-14
Value14
Percentage of DebtInstrumentTenderPremium0.0

cenx:DebtOfferToPurchasePercentageOfOutstandingAmount

cenx:DebtOfferToPurchasePercentageOfOutstandingAmount


Debt
Period End2020-12-31
Value101.0
Percentage of DebtOfferToPurchasePercentageOfOutstandingAmount100.0

cenx:DebtOfferToPurchasePercentageOfOutstandingAmount us-gaap:DebtInstrument, us-gaap:LongtermDebtType

cenx:SeniorSecuredNotes75, us-gaap:SeniorNotes


Debt
Period End2021-06-30
Value101.0
Percentage of DebtOfferToPurchasePercentageOfOutstandingAmount0.0

cenx:DeferredTaxAssetsForeignBasisDifferences

cenx:DeferredTaxAssetsForeignBasisDifferences


Deferred
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-31
Value16151313132.0830.6680.0
Percentage of DeferredTaxAssetsForeignBasisDifferences100.0100.0100.0100.0100.0100.0100.00.0

cenx:EconomicOwnershipPercentageByRelatedParty us-gaap:Ownership

cenx:EconomicOwnershipPercentageByRelatedParty

cenx:Glencore


Economic
Period End2021-06-302021-03-312020-12-312020-09-30
Value46.746.746.846.8
Percentage of EconomicOwnershipPercentageByRelatedParty100.0100.0100.0100.0

cenx:IndustrialRevenueBonds

cenx:IndustrialRevenueBonds


Industrial
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
Value7800000.07800000.07800000.07800000.07800000.07800000.07800000.07800000.07800000.07800000.07800000.07800000.07800000.07800000.07815000.07815000.07815000.07815000.07815000.07815000.07815000.07815000.07815000.07815000.07815000.07815000.07815000.07815000.07815000.07815000.07815000.07815000.07815000.07815000.07815000.07815000.07815000.07815000.07815000.07815000.07815000.07815000.07815000.0
Percentage of IndustrialRevenueBonds100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cenx:IndustrialRevenueBonds us-gaap:DebtInstrument, us-gaap:ShortTermDebtType

cenx:IndustrialRevenueBondsDue2028, us-gaap:ShortTermDebt


Industrial
Period End2021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302012-12-31
Value7800000.07800000.07800000.07800000.07800000.07800000.07800000.07800000.07800000.07800000.07800000.07800000.07800000.07815000.07815000.07815000.07815000.07815000.07815000.07815000.07815000.07815000.07815000.07815000.07815000.07815000.07815000.07815000.07815000.07815000.07815000.07815000.0
Percentage of IndustrialRevenueBonds100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cenx:LineOfCreditFacilityAdditionalBorrowingsUnderLetterOfCreditSubFacility us-gaap:CreditFacility

cenx:LineOfCreditFacilityAdditionalBorrowingsUnderLetterOfCreditSubFacility

us-gaap:LetterOfCredit


Line
Period End2020-12-312020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value9550111127126102106
Percentage of LineOfCreditFacilityAdditionalBorrowingsUnderLetterOfCreditSubFacility100.0100.0100.0100.0100.0100.0100.0

cenx:LineofCreditFacilityRemainingBorrowingCapacityNetofLettersofCredit us-gaap:CreditFacility

cenx:LineofCreditFacilityRemainingBorrowingCapacityNetofLettersofCredit

us-gaap:DomesticLineOfCredit


Lineof
Period End2021-03-312020-09-302020-06-30
Value138318
Percentage of LineofCreditFacilityRemainingBorrowingCapacityNetofLettersofCredit100.0100.0100.0

cenx:LineofCreditFacilityRemainingBorrowingCapacityNetofLettersofCredit us-gaap:CreditFacility, us-gaap:DebtInstrument

us-gaap:DomesticLineOfCredit, us-gaap:RevolvingCreditFacility


Lineof
Period End2021-06-30
Value49
Percentage of LineofCreditFacilityRemainingBorrowingCapacityNetofLettersofCredit0.0

us-gaap:ForeignLineOfCredit, us-gaap:RevolvingCreditFacility


Lineof
Period End2021-06-30
Value50
Percentage of LineofCreditFacilityRemainingBorrowingCapacityNetofLettersofCredit0.0

cenx:LineofCreditFacilityRemainingBorrowingCapacityNetofLettersofCredit us-gaap:CreditFacility, us-gaap:LongtermDebtType

us-gaap:ForeignLineOfCredit, us-gaap:LongTermDebt


Lineof
Period End2021-03-312020-12-312020-09-302020-06-302018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-31
Value505.05.05.0505050505050505050504549
Percentage of LineofCreditFacilityRemainingBorrowingCapacityNetofLettersofCredit362.30.06.027.30.00.00.00.00.00.00.00.00.00.00.00.0

cenx:OtherPrimaryAluminumDeliveryCommitmentsAndContractsOpenPositionVolume us-gaap:DerivativeInstrumentRisk

cenx:OtherPrimaryAluminumDeliveryCommitmentsAndContractsOpenPositionVolume

cenx:FixedtoVariableLondonMetalsExchangeSwap


Other
Period End2021-03-312020-12-312020-09-30
Value175720.0194120.0124380.0
Percentage of OtherPrimaryAluminumDeliveryCommitmentsAndContractsOpenPositionVolume100.0100.0100.0

cenx:OtherShareholdersEquity

cenx:OtherShareholdersEquity


Other
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302016-12-31
Value545591647672674688708727761832852829828772749755
Percentage of OtherShareholdersEquity100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cenx:OtherShareholdersEquity us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

srt:GuarantorSubsidiaries, srt:ReportableLegalEntities


Other
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-12-31
Value586611637650650644636630629711687
Percentage of OtherShareholdersEquity107.6103.398.596.796.593.589.886.782.785.483.0

srt:NonGuarantorSubsidiaries, srt:ReportableLegalEntities


Other
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-12-31
Value-25.7-11.4-4.5-3.72238527293114118
Percentage of OtherShareholdersEquity-4.7-1.9-0.7-0.53.35.67.410.012.313.814.3

srt:ParentCompany, srt:ReportableLegalEntities


Other
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-12-31
Value545591647672674688708727761832828
Percentage of OtherShareholdersEquity100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cenx:OtherShareholdersEquity us-gaap:ConsolidationItems

srt:ConsolidationEliminations


Other
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-12-31
Value-560.8-599.7-633.4-646.6-672.1-682.7-688.9-702.8-722.7-826.0-805.7
Percentage of OtherShareholdersEquity-102.9-101.4-97.8-96.1-99.7-99.1-97.2-96.7-94.9-99.2-97.2

cenx:PercentageOfDomesticWorkForceInUnion

cenx:PercentageOfDomesticWorkForceInUnion


Percentage
Period End2021-06-302021-03-312020-12-312020-09-30
Value58.058.058.057.0
Percentage of PercentageOfDomesticWorkForceInUnion100.0100.0100.0100.0

cenx:PercentageOfForeignWorkForceCoveredUnderNewLaborAgreement

cenx:PercentageOfForeignWorkForceCoveredUnderNewLaborAgreement


Percentage
Period End2021-06-302021-03-312020-12-312020-09-30
Value88.085.086.086.0
Percentage of PercentageOfForeignWorkForceCoveredUnderNewLaborAgreement100.0100.0100.0100.0

cenx:PercentageofWorkForceinUnion

cenx:PercentageofWorkForceinUnion


Percentageof
Period End2021-06-302021-03-312020-12-312020-09-30
Value67.066.067.066.0
Percentage of PercentageofWorkForceinUnion100.0100.0100.0100.0

cenx:PowerSupplyAgreementTotalProductionPercentage dei:LegalEntity, us-gaap:CounterpartyName

cenx:PowerSupplyAgreementTotalProductionPercentage

cenx:SanteeCooper, cenx:Mt.Holly


Power
Period End2020-12-31
Value75.0
Percentage of PowerSupplyAgreementTotalProductionPercentage100.0

cenx:PrimaryAluminumSalesContractsPremiumCollarFairValueDisclosure us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency

cenx:PrimaryAluminumSalesContractsPremiumCollarFairValueDisclosure

us-gaap:FairValueInputsLevel2, us-gaap:FairValueMeasurementsRecurring


Primary
Period End2021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312010-12-31
Value104164.914361.33.84.15.22.00.00.00.00.06.2347.208130.00.00.00.00.00.00.00.00.00.00.00.0
Percentage of PrimaryAluminumSalesContractsPremiumCollarFairValueDisclosure100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.00.00.0100.0100.0100.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:FairValueInputsLevel3, us-gaap:FairValueMeasurementsRecurring


Primary
Period End2021-03-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312010-12-31
Value6.20.81.53.22.91.53.03.60.50.91.51.11.21.4810.3311.90.2530.5740.140.7710.7731.031.171.3791.3611.1690.9080.783
Percentage of PrimaryAluminumSalesContractsPremiumCollarFairValueDisclosure5.916.310.68.9223.139.573.269.225.00.00.00.00.023.84.614.60.00.00.00.00.00.00.00.00.00.00.00.0

cenx:PrimaryAluminumSalesContractsPremiumCollarFairValueDisclosure us-gaap:FairValueByMeasurementFrequency

us-gaap:FairValueMeasurementsRecurring


Primary
Period End2021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312010-12-31
Value111165.715394.25.37.18.82.50.91.51.11.27.7157.539140.2530.5740.140.7710.7731.031.171.3791.3611.1690.9080.783
Percentage of PrimaryAluminumSalesContractsPremiumCollarFairValueDisclosure105.9100.0116.3110.6108.9323.1139.5173.2169.2125.00.00.00.00.0123.8104.6114.60.00.00.00.00.00.00.00.00.00.00.00.0

cenx:SegmentReportingCorporateUnallocatedAssets

cenx:SegmentReportingCorporateUnallocatedAssets


Segment
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-31
Value6766565047464239464327
Percentage of SegmentReportingCorporateUnallocatedAssets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cenx:SegmentReportingPrimaryAssets

cenx:SegmentReportingPrimaryAssets


Segment
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-31
Value13321433148015301492170619711770173017671895
Percentage of SegmentReportingPrimaryAssets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cenx:TrustAssetsFairValueDisclosure

cenx:TrustAssetsFairValueDisclosure


Trust
Period End2020-12-312019-12-312018-12-312017-12-31
Value0.00.20.11.8
Percentage of TrustAssetsFairValueDisclosure0.0100.0100.0100.0

cenx:TrustAssetsFairValueDisclosure us-gaap:FairValueByFairValueHierarchyLevel

us-gaap:FairValueInputsLevel1


Trust
Period End2020-12-312019-12-312018-12-312017-12-31
Value0.00.20.11.8
Percentage of TrustAssetsFairValueDisclosure0.0100.0100.0100.0

cenx:TrustAssetsFairValueDisclosure us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency

us-gaap:FairValueInputsLevel1, us-gaap:FairValueMeasurementsRecurring


Trust
Period End2021-03-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312010-12-31
Value1.50.20.81.30.20.71.10.10.10.50.91.31.7572.1922.7033.1383.1473.6644.1014.7895.2265.9986.6867.3788.0678.8359.523101111121314141515150.0
Percentage of TrustAssetsFairValueDisclosure0.00.00.00.0100.00.00.00.0100.00.00.00.097.60.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

cenx:TrustAssetsFairValueDisclosure us-gaap:FairValueByMeasurementFrequency

us-gaap:FairValueMeasurementsRecurring


Trust
Period End2021-03-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312010-12-31
Value1.50.20.81.30.20.71.10.10.10.50.91.31.7572.1922.7033.1383.1473.6644.1014.7895.2265.9986.6867.3788.0678.8359.523101111121314141515150.0
Percentage of TrustAssetsFairValueDisclosure0.00.00.00.0100.00.00.00.0100.00.00.00.097.60.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

cenx:UnderlyingDerivativeEnergyAvailable us-gaap:DerivativeInstrumentRisk

cenx:UnderlyingDerivativeEnergyAvailable

cenx:NYMEXHenryHubNaturalGasPriceSwaps


Underlying
Period End2020-12-312020-06-302020-03-31
Value2355000.01170000.02340000.0
Percentage of UnderlyingDerivativeEnergyAvailable100.0100.0100.0

cenx:UnderlyingDerivativePowerAvailable us-gaap:CounterpartyName

cenx:UnderlyingDerivativePowerAvailable

cenx:GrundartangiHSLandsvirkjunandOR


Underlying
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-30
Value545.0525.0525.0525.0525.0525.0525.0525.0525.0525.0525.0525.0
Percentage of UnderlyingDerivativePowerAvailable100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cenx:GrundartangiLandsvirkjun


Underlying
Period End2021-06-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-30
Value25.0161.0161.0161.0161.0161.0161.0161.0161.0161.0
Percentage of UnderlyingDerivativePowerAvailable4.630.730.730.730.730.730.730.730.730.7

cenx:UnderlyingDerivativePowerAvailableExtension us-gaap:CounterpartyName

cenx:UnderlyingDerivativePowerAvailableExtension

cenx:GrundartangiLandsvirkjun


Underlying
Period End2021-06-30
Value161.0
Percentage of UnderlyingDerivativePowerAvailableExtension100.0

cenx:UnderlyingDerivativePowerAvailableRequested us-gaap:CounterpartyName

cenx:UnderlyingDerivativePowerAvailableRequested

cenx:GrundartangiLandsvirkjun


Underlying
Period End2021-06-30
Value182.0
Percentage of UnderlyingDerivativePowerAvailableRequested100.0

us-gaap:AccountsPayableTradeCurrent

us-gaap:AccountsPayableTradeCurrent


Accounts
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
Value13311610685878797112981131191131249589979288948589849010911914015189959910810510375757870748684878388
Percentage of AccountsPayableTradeCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:AccountsPayableTradeCurrent us-gaap:ConsolidatedEntities, us-gaap:ConsolidationItems

srt:GuarantorSubsidiaries, srt:ReportableLegalEntities


Accounts
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-12-31
Value6059625866866985848051
Percentage of AccountsPayableTradeCurrent56.869.470.966.768.277.170.575.170.470.457.2

srt:NonGuarantorSubsidiaries, srt:ReportableLegalEntities


Accounts
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-12-31
Value4123232528222625313132
Percentage of AccountsPayableTradeCurrent38.826.926.228.929.520.427.322.526.527.835.8

srt:ParentCompany, srt:ReportableLegalEntities


Accounts
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-12-31
Value4.63.22.53.82.32.92.22.73.72.06.3
Percentage of AccountsPayableTradeCurrent4.33.72.94.42.42.62.22.43.11.87.0

us-gaap:AccumulatedOtherComprehensiveIncomeLossBeforeTax1

us-gaap:AccumulatedOtherComprehensiveIncomeLossBeforeTax1


Accumulated
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302012-12-31
Value-119000000.0-120200000.0-121600000.0-109500000.0-110900000.0-111900000.0-113600000.0-102000000.0-103000000.0-104300000.0-104800000.0-95200000.0-95600000.0-98600000.0-99380000.0-119980000.0-121410000.0-121270000.0-123060000.0-119730000.0-120930000.0-122140000.0-123340000.0-112950000.0-109710000.0-129450000.0-129910000.0-104240000.0-104640000.0-105080000.0-105890000.0-153160000.0-166820000.0
Percentage of AccumulatedOtherComprehensiveIncomeLossBeforeTax1100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:AccumulatedOtherComprehensiveIncomeLossBeforeTax1 us-gaap:StatementEquityComponents

us-gaap:AccumulatedDefinedBenefitPlansAdjustment


Accumulated
Period End2021-06-302021-03-3120