ATI


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

Table of contents



us-gaap:CommonStockValue

us-gaap:WeightedAverageNumberOfDilutedSharesOutstanding

us-gaap:WeightedAverageNumberOfSharesOutstandingBasic

us-gaap:AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount

us-gaap:EarningsPerShareBasic

us-gaap:EarningsPerShareDiluted

us-gaap:IncomeLossFromContinuingOperationsPerBasicShare

us-gaap:IncomeLossFromContinuingOperationsPerDilutedShare

us-gaap:ComprehensiveIncomeNetOfTax

us-gaap:ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest

us-gaap:ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest

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

us-gaap:GainsLossesOnExtinguishmentOfDebt

us-gaap:GrossProfit

us-gaap:IncomeLossFromContinuingOperations

us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest

us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments
us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:StatementEquityComponents
us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:StatementEquityComponents
us-gaap:IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest

us-gaap:IncomeTaxExpenseBenefit
us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:StatementEquityComponents
us-gaap:StatementScenario, us-gaap:CollectiveBargainingArrangement
us-gaap:DerivativeInstrumentRisk, us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:StatementEquityComponents
us-gaap:InterestExpense

us-gaap:NetIncomeLoss

us-gaap:NetIncomeLossAttributableToNoncontrollingInterest

us-gaap:NetIncomeLossAvailableToCommonStockholdersDiluted

us-gaap:OperatingIncomeLoss

us-gaap:OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax

us-gaap:OtherComprehensiveIncomeLossNetOfTax
us-gaap:StatementEquityComponents

us-gaap:OtherNonoperatingIncomeExpense

us-gaap:ProfitLoss
us-gaap:StatementEquityComponents

us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax
us-gaap:ConsolidationItems
us-gaap:ConsolidationItems, us-gaap:ContractWithCustomerSalesChannel, us-gaap:StatementBusinessSegments
us-gaap:ConsolidationItems, us-gaap:MajorCustomers
us-gaap:ConsolidationItems, us-gaap:MajorCustomers, us-gaap:StatementBusinessSegments
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments
us-gaap:ConsolidationItems, us-gaap:StatementGeographical, us-gaap:StatementBusinessSegments
us-gaap:ContractWithCustomerSalesChannel
us-gaap:StatementGeographical

us-gaap:Revenues

us-gaap:SellingGeneralAndAdministrativeExpense

us-gaap:Assets
us-gaap:StatementBusinessSegments
us-gaap:StatementGeographical

us-gaap:Liabilities

us-gaap:LiabilitiesAndStockholdersEquity

us-gaap:StockholdersEquity

us-gaap:AssetsCurrent

us-gaap:Cash

us-gaap:CashAndCashEquivalentsAtCarryingValue
us-gaap:ConsolidationItems
us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName
us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName, us-gaap:StatementBusinessSegments

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents

us-gaap:AccountsReceivableNetCurrent

us-gaap:InventoryNet

us-gaap:InventoryFinishedGoods

us-gaap:InventoryLIFOReserve

us-gaap:InventoryRawMaterialsAndSupplies

us-gaap:OtherAssetsCurrent

us-gaap:Land

us-gaap:MachineryAndEquipmentGross

us-gaap:PropertyPlantAndEquipmentGross

us-gaap:ConstructionInProgressGross

us-gaap:AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment

us-gaap:PropertyPlantAndEquipmentNet

us-gaap:Goodwill
us-gaap:ReportingUnit
us-gaap:StatementBusinessSegments

us-gaap:OtherAssetsNoncurrent

us-gaap:AccountsPayableCurrent

us-gaap:AccruedLiabilitiesCurrent

us-gaap:ContractWithCustomerLiabilityCurrent

us-gaap:DebtCurrent

us-gaap:LiabilitiesCurrent

us-gaap:OtherLiabilitiesCurrent
us-gaap:AdjustmentsForNewAccountingPronouncements, us-gaap:DebtInstrument, us-gaap:LongtermDebtType
us-gaap:LongTermDebt

us-gaap:LongTermDebtAndCapitalLeaseObligations
us-gaap:RetirementPlanType
us-gaap:PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent

us-gaap:MinorityInterest

us-gaap:OtherLiabilitiesNoncurrent

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:StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest
us-gaap:AdjustmentsForNewAccountingPronouncements
us-gaap:AdjustmentsForNewAccountingPronouncements, us-gaap:DebtInstrument, us-gaap:LongtermDebtType
us-gaap:AdjustmentsForNewAccountingPronouncements, us-gaap:StatementEquityComponents
us-gaap:CumulativeEffectPeriodOfAdoption, us-gaap:StatementScenario, us-gaap:DebtInstrument, us-gaap:LongtermDebtType, us-gaap:StatementEquityComponents
us-gaap:StatementEquityComponents

us-gaap:CommonStockValue

us-gaap:AdditionalPaidInCapitalCommonStock

us-gaap:RetainedEarningsAccumulatedDeficit

us-gaap:AccumulatedOtherComprehensiveIncomeLossNetOfTax
us-gaap:StatementEquityComponents

us-gaap:TreasuryStockValue

us-gaap:MinorityInterest

us-gaap:NetCashProvidedByUsedInOperatingActivities

us-gaap:NetCashProvidedByUsedInInvestingActivities

us-gaap:NetCashProvidedByUsedInFinancingActivities

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect
us-gaap:DebtInstrument, us-gaap:LongtermDebtType
us-gaap:AmortizationOfFinancingCosts

us-gaap:DepreciationDepletionAndAmortization
us-gaap:ConsolidationItems
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:IncreaseDecreaseInAccountsReceivable

us-gaap:IncreaseDecreaseInInventories

us-gaap:IncreaseDecreaseInOtherOperatingCapitalNet

us-gaap:NetCashProvidedByUsedInOperatingActivities

us-gaap:NetIncomeLoss

us-gaap:ProfitLoss
us-gaap:StatementEquityComponents

us-gaap:NetCashProvidedByUsedInInvestingActivities

us-gaap:PaymentsToAcquireProductiveAssets

us-gaap:NetCashProvidedByUsedInFinancingActivities

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

us-gaap:EffectiveIncomeTaxRateContinuingOperations

us-gaap:DeferredTaxLiabilities

us-gaap:DeferredTaxAssetsNet
us-gaap:ConsolidationItems

us-gaap:UnrecognizedTaxBenefits

us-gaap:DeferredTaxAssetsValuationAllowance

ati:AdjustedEarningsBeforeIncomeTaxesDepreciationAmortizationEBITDA

ati:AdjustmentsToAdditionalPaidInCapitalConvertibleNoteCappedCall
us-gaap:StatementEquityComponents

ati:ContractwithCustomerAssetCurrentPeriodIncrease

ati:ContractwithCustomerAssetCurrentReclassification

ati:ContractwithCustomerAssetCurrentReclassifiedtoReceivable

ati:ContractwithCustomerAssetNoncurrentReclassification

ati:ContractwithCustomerLiabilityCurrentPeriodIncrease

ati:ContractwithCustomerLiabilityCurrentReclassification

ati:ContractwithCustomerLiabilityCurrentReclassifiedtoRevenue

ati:ContractwithCustomerLiabilityCurrentRevenueRecognized

ati:ContractwithCustomerLiabilityNoncurrentPeriodIncrease

ati:ContractwithCustomerLiabilityNoncurrentReclassification

ati:ContractwithCustomerLiabilityNoncurrentReclassifiedtoRevenue

ati:CorporateExpenses

ati:EmployeeStockPlans
us-gaap:StatementEquityComponents

ati:InterestExpenseNet
us-gaap:DebtInstrument, us-gaap:LongtermDebtType

ati:InventoryNetRealizableValueReservePeriodCharge

ati:Nonoperatingretirementbenefitexpense

ati:OtherComprehensiveIncomeLossBeforeReclassificationAdjustmentsNetOfTaxAttributableToNoncontrollingInterest
us-gaap:StatementEquityComponents

ati:OtherIncomeExpense

ati:OtherNonoperatingIncomeExpenseOther

ati:PaymentOfCappedCallTransactionsCost

ati:PercentageOfForecastedNaturalGasUsageHedgedforYear1

ati:PercentageOfForecastedNaturalGasUsageHedgedforYear2

ati:PercentageOfRawMaterialUsageHedged

ati:RentRoyaltyAndOtherIncome

ati:Restructuringandothercharges

ati:RevenuefromContractwithCustomerExcludingAssessedTaxPercentageofRevenue
us-gaap:ConsolidationItems, us-gaap:ProductOrService, us-gaap:StatementBusinessSegments
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments
us-gaap:ProductOrService

ati:SegmentEarningsBeforeIncomeTaxesDepreciationAmortizationEBITDA
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

ati:SegmentOperatingProfitLoss
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

ati:StrikeRelatedCosts
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:AdjustmentsToAdditionalPaidInCapitalEquityComponentOfConvertibleDebt
us-gaap:StatementEquityComponents

us-gaap:AllowanceForDoubtfulAccountsReceivableWriteOffs

us-gaap:AssetRetirementObligationRevisionOfEstimate

us-gaap:CapitalExpendituresIncurredButNotYetPaid

us-gaap:CapitalizedContractCostAmortization

us-gaap:CashFlowHedgeGainLossToBeReclassifiedWithinTwelveMonths
us-gaap:DebtInstrument, us-gaap:LongtermDebtType
us-gaap:DebtInstrumentConvertibleConversionRatio1
us-gaap:DebtInstrument, us-gaap:LongtermDebtType
us-gaap:DebtInstrumentConvertibleNumberOfEquityInstruments

us-gaap:DeferredIncomeTaxesAndTaxCredits
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanAmortizationOfGainsLosses
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanAmortizationOfPriorServiceCostCredit
us-gaap:StatementScenario, us-gaap:CollectiveBargainingArrangement, us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanBenefitObligationIncreaseDecreaseForRemeasurementDueToSettlement

us-gaap:DefinedBenefitPlanCostOfProvidingSpecialOrContractualTerminationBenefitRecognizedDuringPeriod
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:DerivativeInstrumentRisk, us-gaap:DerivativeInstrumentsGainLossByHedgingRelationship, us-gaap:IncomeStatementLocation
us-gaap:DerivativeInstrumentsGainLossReclassifiedFromAccumulatedOCIIntoIncomeEffectivePortionNet
us-gaap:DerivativeInstrumentsGainLossByHedgingRelationship, us-gaap:IncomeStatementLocation
us-gaap:DerivativeInstrumentRisk
us-gaap:DerivativeNonmonetaryNotionalAmountMass

us-gaap:GainLossOnDispositionOfAssets1

us-gaap:GainLossOnSaleOfProperty

us-gaap:GainLossOnSaleOfPropertyPlantEquipment

us-gaap:GainLossOnSalesOfAssetsAndAssetImpairmentCharges

us-gaap:GoodwillImpairmentLoss

us-gaap:GoodwillPeriodIncreaseDecrease

us-gaap:IncomeLossFromEquityMethodInvestments
us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName, us-gaap:RestructuringCostAndReserve
us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName, us-gaap:StatementBusinessSegments

us-gaap:IncreaseDecreaseInAccountsPayableTrade

us-gaap:IncreaseDecreaseInPensionAndPostretirementObligations
us-gaap:DebtInstrument, us-gaap:LongtermDebtType
us-gaap:InterestExpenseDebtExcludingAmortization

us-gaap:InventoryLIFOReservePeriodCharge
us-gaap:DebtInstrument
us-gaap:LineOfCreditFacilityAverageOutstandingAmount
us-gaap:DebtInstrument
us-gaap:LineOfCreditFacilityInterestRateDuringPeriod

us-gaap:OtherAssetImpairmentCharges

us-gaap:OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditBeforeTax
us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:StatementEquityComponents

us-gaap:OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax
us-gaap:StatementEquityComponents

us-gaap:OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesNetOfTax

us-gaap:OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToNoncontrollingInterest
us-gaap:StatementEquityComponents

us-gaap:OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent
us-gaap:StatementEquityComponents

us-gaap:OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax

us-gaap:OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIOnDerivativesBeforeTax

us-gaap:OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossBeforeTax
us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:StatementEquityComponents

us-gaap:OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodBeforeTax
us-gaap:DerivativeInstrumentRisk, us-gaap:DerivativeInstrumentsGainLossByHedgingRelationship, us-gaap:IncomeStatementLocation
us-gaap:DerivativeInstrumentsGainLossByHedgingRelationship, us-gaap:IncomeStatementLocation

us-gaap:OtherOperatingIncomeExpenseNet

us-gaap:OtherRestructuringCosts

us-gaap:PaymentsForProceedsFromOtherInvestingActivities

us-gaap:PaymentsForRepurchaseOfOtherEquity

us-gaap:PaymentsForRestructuring

us-gaap:PaymentsOfDebtExtinguishmentCosts

us-gaap:PaymentsOfDebtIssuanceCosts

us-gaap:ProceedsFromRepaymentsOfOtherDebt

us-gaap:ProceedsFromSaleOfPropertyPlantAndEquipment

us-gaap:ProvisionForDoubtfulAccounts

us-gaap:ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax
us-gaap:StatementEquityComponents

us-gaap:RepaymentsOfLongTermDebtAndCapitalSecurities

us-gaap:RestructuringAndRelatedCostNumberOfPositionsEliminated

us-gaap:RestructuringCharges
us-gaap:RestructuringCostAndReserve

us-gaap:SeveranceCosts1

us-gaap:ValuationAllowanceDeferredTaxAssetChangeInAmount
us-gaap:DebtInstrument, us-gaap:LongtermDebtType
us-gaap:WriteOffOfDeferredDebtIssuanceCost

ati:Accountsreceivablewithcustomers

ati:AccumulatedOtherComprehensiveIncomeLossNetofTaxAttributabletoNoncontrollingInterest
us-gaap:StatementEquityComponents
us-gaap:RetirementPlanType
ati:DeferredTaxAssetsOtherComprehensiveIncomeLossDefinedBenefitPlans

ati:DeferredTaxLiabilitiesInventory
us-gaap:RetirementPlanType
ati:DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetOfTaxEffect
us-gaap:RetirementPlanSponsorLocation, us-gaap:RetirementPlanType
ati:DefinedBenefitPlanPercentOfEmployeesaccruingbenefitservice
us-gaap:RetirementPlanSponsorLocation
ati:DefinedBenefitPlanPlanAssetsPledgedAsCollateral

ati:DefinedContributionPlanDeferredContributionsDueToCOVID19Pandemic
us-gaap:RetirementPlanSponsorLocation, us-gaap:RetirementPlanType
ati:Definedbenefitplannumberofemployeesaccruingbenefitservice

ati:EntityNumberOfEmployeesCoveredByUSWCollectiveBargainingAgreementsExpiringFebruary282021
us-gaap:StatementGeographical
ati:EntityWideDisclosureOnGeographicAreasTotalAssetsAttributedToIndividualCountriesPercentageAmount

ati:EnvironmentalRemediationObligationForFormerlyOwnedSites

ati:EnvironmentalRemediationObligationForOwnedOrControlledSitesWithClosedOperations
us-gaap:DefinedBenefitPlanByPlanAssetCategories, us-gaap:RetirementPlanType
ati:FairValueInvestmentsUnfundedCommitments
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:MeasurementInputType
ati:GoodwillMeasurementInput
us-gaap:Range, us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:MeasurementInputType
us-gaap:StatementScenario
ati:LesseeFinanceLeaseLeaseNotYetCommencedLiabilityToBeRecognized
us-gaap:StatementScenario
ati:LesseeFinanceLeaseLeaseNotYetCommencedRightOfUseAssetToBeRecognized
us-gaap:StatementScenario, us-gaap:CreditFacility, us-gaap:DebtInstrument
ati:LineofCreditFacilityIncreasetoMaximumBorrowingCapacity
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:MeasurementInputType, us-gaap:PropertyPlantAndEquipmentByType
ati:LongLivedAssetMeasurementInput
us-gaap:RetirementPlanSponsorLocation, us-gaap:RetirementPlanType
ati:PercentageOfTotalAssetsUsQualifiedPlan

ati:ProgressPaymentsMadeOnBehalfOfCompanyPaid

ati:ProgressPaymentsMadeOnBehalfOfCompanyScheduledToBePaid

ati:RetainedEarningsEquityMethodUndistributedEarnings

ati:RevenueRemainingPerformanceObligationCurrent
us-gaap:Range, us-gaap:AwardType, us-gaap:PlanName
ati:SharebasedCompensationArrangementbySharebasedPaymentAwardExpectedCompensationCost

ati:TotalDebt

ati:UnrecognizedTaxBenefitsReductionofOperatingLossCarryforwards

dei:EntityNumberOfEmployees
us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName
us-gaap:AccountsReceivableRelatedPartiesCurrent

us-gaap:AccrualForEnvironmentalLossContingencies

us-gaap:AllowanceForDoubtfulAccountsReceivable

us-gaap:AssetRetirementObligation

us-gaap:BuildingsAndImprovementsGross

us-gaap:CapitalizedContractCostNet
us-gaap:FairValueByFairValueHierarchyLevel
us-gaap:CashAndCashEquivalentsFairValueDisclosure
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementBasis
us-gaap:FairValueByMeasurementBasis

us-gaap:ContractWithCustomerAssetNetCurrent

us-gaap:ContractWithCustomerLiabilityNoncurrent
us-gaap:DebtInstrument
us-gaap:DebtInstrumentCarryingAmount
us-gaap:DebtInstrument, us-gaap:LongtermDebtType, us-gaap:SubsequentEventType
us-gaap:LongtermDebtType
us-gaap:DebtInstrument, us-gaap:LongtermDebtType
us-gaap:DebtInstrumentConvertibleCarryingAmountOfTheEquityComponent
us-gaap:FairValueByFairValueHierarchyLevel
us-gaap:DebtInstrumentFairValue
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementBasis
us-gaap:FairValueByMeasurementBasis
us-gaap:DebtInstrument, us-gaap:LongtermDebtType
us-gaap:DebtInstrumentInterestRateEffectivePercentage
us-gaap:DebtInstrument, us-gaap:LongtermDebtType
us-gaap:DebtInstrumentRepurchasedFaceAmount

us-gaap:DeferredFinanceCostsNet
us-gaap:BalanceSheetLocation, us-gaap:DebtInstrument, us-gaap:LongtermDebtType
us-gaap:DebtInstrument, us-gaap:LongtermDebtType

us-gaap:DeferredIncomeTaxLiabilities

us-gaap:DeferredTaxAssetsGross

us-gaap:DeferredTaxAssetsOperatingLossCarryforwards

us-gaap:DeferredTaxAssetsOther

us-gaap:DeferredTaxAssetsTaxCreditCarryforwards

us-gaap:DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsPensions

us-gaap:DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsPostretirementBenefits

us-gaap:DeferredTaxLiabilitiesGoodwillAndIntangibleAssets

us-gaap:DeferredTaxLiabilitiesOther

us-gaap:DeferredTaxLiabilitiesPropertyPlantAndEquipment

us-gaap:DeferredTaxLiabilitiesUndistributedForeignEarnings

us-gaap:DefinedBenefitPensionPlanLiabilitiesNoncurrent
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanAccumulatedBenefitObligation
us-gaap:CollectiveBargainingArrangement, us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeBeforeTax
us-gaap:RetirementPlanType
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetGainsLossesBeforeTax
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetPriorServiceCostCreditBeforeTax
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanAmountsRecognizedInBalanceSheet
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanAssetsForPlanBenefitsNoncurrent
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanBenefitObligation

us-gaap:DefinedBenefitPlanExpectedAmortizationNextFiscalYear
us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanExpectedAmortizationOfGainLossNextFiscalYear
us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanExpectedAmortizationOfPriorServiceCostCreditNextFiscalYear
us-gaap:RetirementPlanType
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:RetirementPlanSponsorLocation, us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanExpectedFutureEmployerContributionsNextFiscalYear
us-gaap:RetirementPlanTaxStatus, us-gaap:RetirementPlanType
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanHealthCareCostTrendRateAssumedNextFiscalYear
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateAccumulatedBenefitObligation
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateFairValueOfPlanAssets
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateProjectedBenefitObligation
us-gaap:FairValueByFairValueHierarchyLevel
us-gaap:DerivativeAssets
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementBasis
us-gaap:FairValueByMeasurementBasis

us-gaap:DerivativeFairValueOfDerivativeAsset
us-gaap:BalanceSheetLocation, us-gaap:DerivativeInstrumentRisk, us-gaap:HedgingDesignation
us-gaap:HedgingDesignation

us-gaap:DerivativeFairValueOfDerivativeLiability
us-gaap:BalanceSheetLocation, us-gaap:DerivativeInstrumentRisk, us-gaap:HedgingDesignation
us-gaap:HedgingDesignation
us-gaap:FairValueByFairValueHierarchyLevel
us-gaap:DerivativeLiabilities
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementBasis
us-gaap:FairValueByMeasurementBasis
us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName, us-gaap:FairValueByAssetClass, us-gaap:StatementBusinessSegments
us-gaap:DueFromAffiliates
us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName, us-gaap:StatementBusinessSegments

us-gaap:EmployeeRelatedLiabilitiesCurrent
us-gaap:AwardType
us-gaap:EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized
dei:LegalEntity, us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName
us-gaap:EquityMethodInvestmentOwnershipPercentage
us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName
us-gaap:DefinedBenefitPlanByPlanAssetCategories, us-gaap:RetirementPlanType
us-gaap:FairValueInvestmentsEntitiesThatCalculateNetAssetValuePerShareUnfundedCommittments

us-gaap:FinanceLeaseLiability

us-gaap:FinanceLeaseLiabilityPaymentsDue

us-gaap:FinanceLeaseLiabilityPaymentsDueAfterYearFive

us-gaap:FinanceLeaseLiabilityPaymentsDueNextTwelveMonths

us-gaap:FinanceLeaseLiabilityPaymentsDueYearFive

us-gaap:FinanceLeaseLiabilityPaymentsDueYearFour

us-gaap:FinanceLeaseLiabilityPaymentsDueYearThree

us-gaap:FinanceLeaseLiabilityPaymentsDueYearTwo

us-gaap:FinanceLeaseLiabilityUndiscountedExcessAmount

us-gaap:FinanceLeaseWeightedAverageDiscountRatePercent

us-gaap:FiniteLivedIntangibleAssetsAccumulatedAmortization
us-gaap:FiniteLivedIntangibleAssetsByMajorClass

us-gaap:FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths

us-gaap:FiniteLivedIntangibleAssetsAmortizationExpenseYearFive

us-gaap:FiniteLivedIntangibleAssetsAmortizationExpenseYearFour

us-gaap:FiniteLivedIntangibleAssetsAmortizationExpenseYearThree

us-gaap:FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo

us-gaap:FiniteLivedIntangibleAssetsGross
us-gaap:FiniteLivedIntangibleAssetsByMajorClass

us-gaap:GoodwillImpairedAccumulatedImpairmentLoss

us-gaap:InterestPayableCurrent

us-gaap:InventoryGross

us-gaap:InventoryValuationReserves
us-gaap:PublicUtilitiesInventory

us-gaap:InventoryWorkInProcess

us-gaap:LIFOInventoryAmount

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths
us-gaap:DebtInstrument
us-gaap:LineOfCredit

us-gaap:LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths

us-gaap:LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour

us-gaap:LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree

us-gaap:LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo

us-gaap:LossContingencyRangeOfPossibleLossPortionNotAccrued
us-gaap:Ownership, us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName, us-gaap:RelatedPartyTransactionsByRelatedParty
us-gaap:MinorityInterestOwnershipPercentageByNoncontrollingOwners
us-gaap:Ownership, us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName, us-gaap:RelatedPartyTransactionsByRelatedParty, us-gaap:StatementBusinessSegments
us-gaap:Ownership, us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName
us-gaap:MinorityInterestOwnershipPercentageByParent
us-gaap:Ownership, us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName, us-gaap:StatementBusinessSegments

us-gaap:MoneyMarketFundsAtCarryingValue
us-gaap:RetirementPlanName, us-gaap:RetirementPlanType
us-gaap:MultiemployerPlansWithdrawalObligation

us-gaap:OperatingLeaseWeightedAverageDiscountRatePercent
ati:ExpirationPeriod, us-gaap:IncomeTaxAuthority
us-gaap:OperatingLossCarryforwards
us-gaap:IncomeTaxAuthority

us-gaap:OtherPostretirementDefinedBenefitPlanLiabilitiesNoncurrent
us-gaap:CollectiveBargainingArrangement, us-gaap:RetirementPlanType
us-gaap:RetirementPlanType
us-gaap:PensionAndOtherPostretirementDefinedBenefitPlansCurrentLiabilities
us-gaap:RetirementPlanType
us-gaap:PrescriptionDrugSubsidyReceiptsAfterYearFive
us-gaap:RetirementPlanType
us-gaap:PrescriptionDrugSubsidyReceiptsNextTwelveMonths
us-gaap:RetirementPlanType
us-gaap:PrescriptionDrugSubsidyReceiptsYearFive1
us-gaap:RetirementPlanType
us-gaap:PrescriptionDrugSubsidyReceiptsYearFour1
us-gaap:RetirementPlanType
us-gaap:PrescriptionDrugSubsidyReceiptsYearThree1
us-gaap:RetirementPlanType
us-gaap:PrescriptionDrugSubsidyReceiptsYearTwo1
us-gaap:PropertyPlantAndEquipmentByType
us-gaap:PropertyPlantAndEquipmentFairValueDisclosure
us-gaap:ReportingUnit
us-gaap:ReportingUnitPercentageOfFairValueInExcessOfCarryingAmount

us-gaap:RestructuringReserve
us-gaap:BalanceSheetLocation
us-gaap:RestructuringCostAndReserve

us-gaap:RevenueRemainingPerformanceObligation

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant
us-gaap:AwardType, us-gaap:PlanName
us-gaap:DebtInstrument
us-gaap:ShortTermBorrowings

us-gaap:SignificantChangeInUnrecognizedTaxBenefitsIsReasonablyPossibleAmountOfUnrecordedBenefit
ati:ExpirationPeriod, us-gaap:IncomeTaxAuthority
us-gaap:TaxCreditCarryforwardAmount
ati:ExpirationPeriod, us-gaap:IncomeTaxAuthority, us-gaap:TaxCreditCarryforward
us-gaap:IncomeTaxAuthority
us-gaap:IncomeTaxAuthority, us-gaap:TaxCreditCarryforward

us-gaap:UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued

us-gaap:UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate

us-gaap:UnrecordedUnconditionalPurchaseObligationBalanceSheetAmount

Plots across concepts


IncomeStatement
Net Income Loss
Expenses
Other Nonoperating Income Expense
Balance Sheet
Operating Lease Liability
Assets
Cash And Cash Equivalents At Carrying Value
Current Assets
Other Assets Current
NonCurrent Assets
Goodwill
PropertyPlantAndEquipmentNet
Property Plant And Equipment Net
Liabilities
Operating Lease Liability
Current Liabilities
Debt Current
Noncurrent Liabilities
Minority Interest
Stockholders Equity
Accumulated Other Comprehensive Income Loss Net Of Tax
CashFlow
Net Income Loss
NetCashProvidedByUsedInOperatingActivities
Increase Decrease In Accounts Receivable
NetCashProvidedByUsedInInvestingActivities
Net Cash Provided By Used In Investing Activities
NetCashProvidedByUsedInFinancingActivities
Net Cash Provided By Used In Financing Activities
Shares
Weighted Average Number Of Diluted Shares Outstanding
LesseeOperatingLeaseLiabilityPaymentsDue
Lessee Operating Lease Liability Payments Due Year Four
InventoryNet
Inventory Finished Goods

Tables

  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
us-gaap:CommonStockValue ███████████████▃▃▃▃▃▃▃▃▃▃▃▃▃▃▃▃▃▃▃▃▃▃▃▃▃▃▁▁12.712.712.712.712.712.712.712.712.712.712.712.712.712.712.711.011.011.011.011.011.011.011.011.011.011.011.011.011.011.011.011.011.011.011.011.011.011.011.011.011.010.210.2NANANA10.2NANANA
us-gaap:WeightedAverageNumberOfDilutedSharesOutstanding █▁127.1126.8NA126.6126.6146.4NA146.7146.4126.1NA146.0145.8145.5NA107.7128.3128.2NA107.3107.3107.3NA107.3107.3108.0NA108.0107.1107.0NA106.8107.2107.1NA116.7116.6116.4NA116.4113.5109.0NA98.6108.498.7NANANANA
us-gaap:WeightedAverageNumberOfSharesOutstandingBasic ██████████████▆▃▃▃▄▃▃▃▄▃▃▃▄▃▃▃▃▃▃▃▃▃▃▃▃▃▂▁▁▁▁▁▁▁▁▁127.1126.8126.8126.6126.6126.1126.1125.9125.9125.4125.7125.2125.2125.0118.6107.7107.7107.5108.9107.3107.3107.3109.171124107.3107.3107.2108.704983107.2107.1107.0107.984535106.8106.8106.6107.321941106.2106.1105.9106.358868105.1102.197.698.59374598.57611798.56377498.31731998.07558798.07418698.03366397.596689
us-gaap:AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount ▄▄25.725.7NA25.020.50.0NA0.00.019.9NA0.00.00.0NA20.90.00.0NA21.09.30.8NA0.81.20.0NA0.07.010.0NA10.09.69.6NA0.00.00.0NANANANANANANANANANANANA
us-gaap:EarningsPerShareBasic ▇▇▁▇▅▇▇█▇▇▇▇▇▇▇▆▇▇▇▄▇▆▅▆▇▇▇▇▇▇█▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇-0.39-0.06-8.85-0.4-3.340.170.450.880.60.120.330.40.580.460.01-1.120.090.160.09-4.95-0.18-0.94-2.12-1.35-0.150.090.2-0.01-0.03-0.191.62-0.320.040.090.10.330.530.530.30.590.630.580.160.010.370.190.390.01-0.140.06
us-gaap:EarningsPerShareDiluted ▇▇▁▇▅▇▇▇▇▇▇▇▇▇▇▆▇▇▇▄▇▆▅▆▇▇▇▇▇▇█▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇-0.39-0.06-8.85-0.4-3.340.160.410.780.540.120.30.370.520.420.01-1.120.090.160.09-4.95-0.18-0.94-2.12-1.35-0.150.090.2-0.01-0.03-0.191.62-0.320.040.090.10.320.50.50.290.560.590.540.150.010.360.180.360.01-0.140.06
us-gaap:IncomeLossFromContinuingOperationsPerBasicShare ▇▇▁▇▅▇███▇████▇▇▇▇▇▄▇▇▆▆▇▇▇▇▇▇▇▇▇▇▇███-3.9e-07-6e-08-8.86e-06-4.0000000000000003e-07-3.3399999999999998e-061.7000000000000001e-074.499999999999997e-078.8e-076e-071.2e-073.3000000000000007e-074.0000000000000003e-075.8e-074.6000000000000004e-074.0000000000000034e-08-1.12e-069e-081.6e-071.0000000000000054e-07-4.95e-06-1.8e-07-9.399999999999999e-07-2.12e-06-1.35e-06-1.5e-079e-081.8e-070.0-3e-08-1.7000000000000001e-07-7.900000000000001e-07-2.7e-074e-089e-081.5e-073e-074.8e-074.9e-07NANANANANANANANANANANANA
us-gaap:IncomeLossFromContinuingOperationsPerDilutedShare ▇▇▁▇▅█████████▇▇▇██▄▇▇▆▆▇▇█▇▇▇▇▇▇▇████-3.9e-07-6e-08-8.86e-06-4.0000000000000003e-07-3.3399999999999998e-061.6e-074.1000000000000015e-077.8e-075.4e-071.2e-073.0000000000000004e-073.7e-075.2e-074.2e-074.0000000000000034e-08-1.12e-069e-081.6e-071.0000000000000054e-07-4.95e-06-1.8e-07-9.399999999999999e-07-2.12e-06-1.35e-06-1.5e-079e-081.8e-070.0-3e-08-1.7000000000000001e-07-7.900000000000001e-07-2.7e-074e-089e-081.5e-072.9e-074.6000000000000004e-074.6000000000000004e-07NANANANANANANANANANANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
us-gaap:ComprehensiveIncomeNetOfTax ▆▆▁▆▅▆▆▇▆▆▆▆▆▇▆▆▆▆▆▄▆▆▅▅▆▆▅▆▆▆█▆▆▆▆▆▆▆▅▆▆▆-16.97.1-1216.0-5.9-378.86.2-83.8134.086.253.3-101.450.873.493.6-9.8-70.314.339.8-122.1-518.82.4-81.6-316.0-162.77.110.6-255.79.926.0-1.0442.8-11.615.823.2-143.071.869.772.1-272.664.673.472.4NANANANANANANANA
us-gaap:ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest ▆▆█▇▄▄▅▃▃▆▄▁▃▇▅▆▄▅▂▄▄▄▄▂▄▄▄▅▄▃▄▄▅▄▅▄▃▄6.76.111.49.12.21.75.2-0.3-0.26.52.9-3.9-0.39.43.96.83.55.6-1.32.01.81.61.8-0.83.02.42.35.42.20.23.11.74.12.14.92.61.12.7NANANANANANANANANANANANA
us-gaap:ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest ▆▆▁▆▅▆▆▇▆▆▆▆▆▇▆▆▆▆▆▄▆▆▅▅▆▆▅▆▆▆█▆▆▆▆▆▆▆▅▆▆▆▆▆▆▆-10.213.2-1204.63.2-376.67.9-78.6133.786.059.8-98.546.973.1103.0-5.9-63.517.845.4-123.4-516.84.2-80.0-314.2-163.510.113.0-253.415.328.2-0.8445.9-9.919.925.3-138.174.470.874.8-269.068.077.076.48.013.349.119.9NANANANA
us-gaap:CostOfGoodsAndServicesSold ▁▂▂▁▄▆▇▇█▇█▇▇▇▅▅▅573.5606.7613.1000000000003559.9695.6820.7849.3859.0902.7873.7890.3859.8835.8830.4767.3763.8755.9NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:GainsLossesOnExtinguishmentOfDebt NANA0.00.0-21.5NA-21.6NA0.0NANANANANA-37.0NANANANANANANANANANANANANANANANANANANANANANANANANANA0.0NANANA0.0NANANANA
us-gaap:GrossProfit ▄▅▄▄▅▆▇▇▇▆▆▇▇▆▆▅▆▆▅▄▄▂▁▃▅▆▆▅▅▅▃▄▅▅▆▇▇█▇███▆▅▆▆▇▅▅▅42.785.845.238.174.7134.8169.3159.7177.7131.1147.6160.4173.7148.6130.693.3112.3112.897.350.248.2-33.2-97.5-28.777.0109.5121.997.089.570.211.353.187.7100.5124.5162.8198.9207.0169.0215.8223.0205.4127.389.8151.8121.4158.494.175.280.7
us-gaap:IncomeLossFromContinuingOperations ▇▇▁▇▅▇███▇████▇▇▇▇▇▄▇▇▆▇▇▇▇▇▇▇▇▇▇▇▇███-49.2-7.9-1121.0-50.1-422.621.156.5111.075.115.041.150.572.858.01.7-121.210.117.59.9-530.8-18.8-101.2-226.9-144.6-16.410.019.90.0-3.8-18.1-83.8-28.43.79.716.031.351.451.8NANANANANANANANANANANANA
us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest ▇▇▁▇▆█▇██▇████▇▇▇▇-40.43.1-1142.8-46.2-327.334.421.2119.084.317.139.262.580.565.50.4-121.311.323.1NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments ▁█-40.43.1NA-46.2-327.334.4NA119.084.317.1NA62.580.565.5NA-121.311.323.1NA-531.5-41.4-132.3-359.1-117.9-21.620.626.84.1-3.4-26.0-140.8-35.37.715.316.154.189.784.149.995.4100.393.822.69.560.633.0NANANANA
 us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome,us-gaap:StatementEquityComponents us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome,us-gaap:AccumulatedDefinedBenefitPlansAdjustment▄▄-21.7-21.7NA-20.5-20.5-20.6NA-21.2-21.2-21.1NA-18.5-18.5-18.6NA-17.4-17.6-17.4NA-18.3-18.3-19.6NA-20.3-20.2-20.2NA-21.9-21.9-21.8NA-29.7-29.7-29.7NANANANANANANANANANANANANANANANA
 us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome,us-gaap:StatementEquityComponents us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome,us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedges▁█1.51.7NA-0.4-4.2-1.8NA0.8-0.5-0.9NA2.64.73.0NA1.21.40.9NA-0.6-2.9-5.0NA3.32.12.7NA2.60.5-2.1NA-4.3-0.5-0.7NANANANANANANANANANANANANANANANA
 us-gaap:IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome,us-gaap:StatementEquityComponents us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome,us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedges▅▅▄▄▂▃▆▅▄▄▅▅▆▆▆▅▅▅▄▄▃▂█▅▅▅▅▅▄▃▁▃▄▄1.11.30.3-0.3-3.2-1.43.50.7-0.4-0.71.12.03.52.32.30.80.80.60.4-0.4-1.8-3.16.32.01.31.71.61.60.3-1.3-5.2-2.6-0.4-0.4NANANANANANANANANANANANANANANANA
us-gaap:IncomeTaxExpenseBenefit ▅▅▄▅█▅▄▅▅▅▅▅▅▅▅▅▅▅▄▅▄▄▁▆▅▅▅▅▅▅█▅▅▅▅▅▆▆▅▆▆▆▅▅▆▅4.05.5-26.50.892.610.8-38.83.75.80.8-5.86.94.95.0-4.8-1.9-2.12.0-42.5-4.3-25.9-34.2-135.823.4-7.78.03.70.5-2.9-10.0102.2-8.51.13.72.616.831.025.815.731.234.335.15.26.222.413.2NANANANA
 us-gaap:InterestExpense us-gaap:DerivativeInstrumentRisk,us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome,us-gaap:StatementEquityComponents us-gaap:InterestRateSwap,us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome,us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedges▄▅█▄█▄▁▅▂▂▄▂▁▁▁▁0.20.30.50.20.50.20.00.30.10.10.20.10.00.00.00.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:NetIncomeLoss ▇▇▁▇▅▇▇█▇▇▇▇▇▇▇▆▇▇▇▄▇▇▆▆▇▇▇▇▇▇█▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇-49.2-7.9-1121.0-50.1-422.621.156.5111.075.115.041.150.572.858.01.7-121.210.117.59.9-530.8-18.8-101.2-226.9-144.6-16.410.022.1-0.7-4.0-20.0173.4-33.84.410.010.535.356.456.231.762.364.056.315.11.036.418.237.81.4-13.45.9
us-gaap:NetIncomeLossAttributableToNoncontrollingInterest ▇█▇▄▃▃▅▆▄▁▅▇▃▃▅▂▄▅▅▅▄▄▅▄▃▃▄▅▄▂▂▂▂▂▄▂▃▂▃▂▂▃▃▃▂▂4.85.54.6999999999999993.12.72.53.54.33.41.33.95.12.82.53.51.83.33.63.83.63.33.13.63.32.52.63.23.63.32.12.21.62.21.63.02.02.32.12.51.92.02.42.32.31.81.6NANANANA
us-gaap:NetIncomeLossAvailableToCommonStockholdersDiluted ▇▇▁▇▅▇███▇████▇▇▇▇▇▄▇▇▆▇▇▇▇▇▇▇▇▇▇▇▇███████▇▇█▇-49.2-7.9-1121.0-50.1-422.623.459.6114.278.315.044.453.776.061.21.7-121.211.920.59.9-530.8-18.8-101.2-226.9-144.8-16.49.919.60.0-3.8-18.1-83.8-28.44.410.012.537.458.558.534.164.866.558.815.11.038.618.2NANANANA
us-gaap:OperatingIncomeLoss ▇▇▁▇▆██████████▇██▇▄▇▇▅▇▇██▇▇▇▇▇▇▇▇████████▇██-11.331.8-1088.1-9.6-273.468.498.594.5110.063.174.794.9111.081.568.7-87.345.653.33.4-498.9-12.1-104.8-329.2-91.24.646.451.528.323.82.5-122.5-17.521.728.632.571.1108.2103.671.6119.1123.7116.738.523.975.847.2NANANANA
us-gaap:OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax █▁7.0-4.8NA23.214.2-23.49.8-16.3-8.511.0-10.2-13.8-26.223.60.124.24.410.4-27.5-4.4-9.8-5.4-18.3-16.219.3-21.8-21.4-16.67.7-3.311.412.44.5-13.04.215.3-14.69.4-1.4-14.4NANANANANANANANANANA
us-gaap:OtherComprehensiveIncomeLossNetOfTax ▅▅▄▅▅▅▃▅▅▅▃▅▅▅▅▅▅▅▃▅▅▅▄▄▅▅▁▅▅▅█▅▅▅▃▅▅▅▁▅34.215.6-88.350.243.3-15.7-138.618.47.543.5-143.5-8.7-2.542.5-11.155.94.424.3-137.110.419.718.1-90.9-22.224.00.4-278.712.428.917.1270.322.313.313.7-151.637.112.116.5-303.23.8NANANANANANANANANANA
us-gaap:OtherNonoperatingIncomeExpense ▂▂▂▂▂▂▁█▄▂▂▂▂▄▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂1.41.5-0.4-0.40.5-0.9-13.267.218.6-2.9-1.90.83.817.80.30.20.23.30.60.01.00.8-0.70.80.60.91.21.01.30.60.40.4-0.11.1-0.50.20.10.40.5-0.30.30.10.42.00.20.4NANANANA
us-gaap:ProfitLoss ▇▇▁▇▅▇▇█▇▇▇▇▇▇▇▆▇▇▇▄▇▇▆▆▇▇▇▇▇▇█▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇-44.4-2.4-1116.3-47.0-419.923.660.0115.378.516.345.055.675.660.55.2-119.413.421.113.7-527.2-15.5-98.1-223.3-141.3-13.912.625.32.9-0.7-17.9175.6-32.26.611.613.537.358.758.334.264.266.058.717.43.338.219.8NANANANA
 us-gaap:ProfitLoss us-gaap:StatementEquityComponents us-gaap:NoncontrollingInterest▇█▇▄▃▃▅▆▄▁▅▇▃▃▅▂▄▅▅▅▄▄▅▄▃▃4.85.54.6999999999999993.12.72.53.54.33.41.33.95.12.82.53.51.83.33.63.83.63.33.13.63.32.52.6NANA3.32.12.21.62.21.63.02.02.32.12.51.92.02.42.32.31.81.6NANANANA
 us-gaap:ProfitLoss us-gaap:StatementEquityComponents us-gaap:RetainedEarnings▇▇▁▇▅▇▇█▇▇▇▇▇▇▇▆▇▇▇▄▇▇▆▆▇▇▇▇▇▇█▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇-49.2-7.9-1121.0-50.1-422.621.156.5111.075.115.041.150.572.858.01.7-121.210.117.59.9-530.8-18.8-101.2-226.9-144.6-16.410.022.1-0.7-4.0-20.0173.4-33.84.410.010.535.356.456.231.762.364.056.315.11.036.418.2NANANANA
us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax ▁▂▂▁▃▄▅▅▅▅▅▅▅▅▄▃▄▃▃▃▃▂▂▃▅▆▅▅▆▅▄▄▆▆▅▇██▇██▇▅▅▅▄▃▂▂▃616.2692.5658.3598.0770.3955.51018.61018.71080.41004.81037.91020.21009.5979.0909.9869.1880.2865.9796.1770.5810.5757.5738.9832.71022.51125.51047.51069.61119.0987.3915.3972.41135.51179.41021.41220.51357.41352.51251.41352.61351.61227.41037.61058.81052.0899.4815.7697.6710.0831.6
us-gaap:Revenues ▁▂▂▁▃▄▅▅▅▅▅▅▅▅▄▃▄▃▃▃▃▂▂▃▅▆▅▅▆▅▄▄▆▆▅▇██▇██▇▅▅▅▄▃▂▂▃616.2692.5658.3598.0770.3955.51018.61018.71080.41004.81037.91020.21009.5979.0909.9869.1880.2865.9796.1770.5810.5757.5738.9832.71022.51125.51047.51069.61119.0987.3915.3972.41135.51179.41021.41220.51357.41352.51251.41352.61351.61227.41037.61058.81052.0899.4815.7697.6710.0831.6
us-gaap:SellingGeneralAndAdministrativeExpense ▃▂▂▂▁▃▄▄▄▄▅▄▃▄▃▄▄▃▄▃▃▃▁▃▅▃▄▄▄▄▄▄▆▆▇▇▇█▇▇█▆▆▄▅▅60.254.052.845.444.458.466.365.267.768.072.965.562.767.161.966.266.759.565.360.559.362.640.862.572.463.170.468.765.767.766.370.682.185.792.091.790.7103.497.496.799.388.788.865.976.074.2NANANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
us-gaap:Assets ▁▁▁▄▄▅▅▅▅▅▅▄▄▄▄▄▄▄▄▄▅▅▅▆▇▇▇▇▇██▇▆▆▆▆▆▆▆▆▆▄▂3974.04068.54034.95063.95169.45807.15634.65628.95549.35491.05501.85389.05393.35350.05185.45075.15186.35154.45170.05192.35861.05719.15751.76161.16469.36556.86582.66503.26570.96917.56898.56599.36119.66174.36247.86078.86080.06078.76046.96127.06049.05192.54493.6NANANA4346.0NANANA
us-gaap:Liabilities ▅▆▅▅▅▆▆▅▅▆▆▅▅▅▅▆▆▆▇▆▇▆▆▆▇▇▇▆▆█▇█▆▆▆▅▅▆▆▅▅▄▁3367.93459.23393.53214.13327.13614.53441.43349.03410.73444.43510.23305.83351.43386.73340.93627.63671.93665.03725.23629.63761.73614.63555.23643.53756.53836.73861.23511.53580.23938.23903.84035.23532.73577.63660.73333.93404.53464.83475.33285.73269.02989.42364.2NANANA2256.4NANANA
us-gaap:LiabilitiesAndStockholdersEquity ▁▁▁▄▄▅▅▅▅▅▅▄▄▄▄▄▄▄▄▄▅▅▅▆▇▇▇▇▇██▇▆▆▆▆▆▆▆▆▆▄▂3974.04068.54034.95063.95169.45807.15634.65628.95549.35491.05501.85389.05393.35350.05185.45075.15186.35154.45170.05192.35861.05719.15751.76161.16469.36556.86582.66503.26570.96917.56898.56599.36119.66174.36247.86078.86080.06078.76046.96127.06049.05192.54493.6NANANA4346.0NANANA
us-gaap:StockholdersEquity ▁▁▁▅▅▆▆▆▅▅▅▅▅▅▅▄▄▄▄▄▅▅▆▇▇▇▇████▇▇▇▇▇▇▇▇█▇▆▆473.0482.9521.11733.71735.32087.82090.12168.02026.41934.21885.71980.21925.01846.11739.41347.81413.51394.21355.21471.81994.41995.22082.82405.72584.32594.62598.42871.22875.72866.32894.22466.72491.22487.12479.62642.32575.52515.02475.32748.72690.72110.52040.8NANANA2012.2NANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
us-gaap:AssetsCurrent ▂▃▃▃▄▅▄▅▄▃▄▃▃▃▂▁▁▁▁▁▂▁▂▃▅▅▅▅▅██▆▄▅▅▅▆▆▆▆▆▇▃1996.52093.42066.02086.32201.62508.02303.02422.42261.42177.92246.72122.42126.32051.81915.71804.11800.11762.61766.51762.11952.41800.71867.62098.62383.52465.62482.12415.02513.82895.72950.82693.52331.82446.42510.62484.82527.52574.72569.52689.52691.12787.12115.1NANANA1997.6NANANA
us-gaap:Cash NANA158.2NANANA190.8NANANA264.4NANANA140.2NANANA164.1NANANA149.3NANANA267.7NANANA1025.2NANANA222.8NANANA339.6NANANA256.8NANANA245.1NANANA
us-gaap:CashAndCashEquivalentsAtCarryingValue ▄▄▅▅▄▅▄▄▃▂▃▂▁▁▁▁▂▂▂▂▃▂▂▂▂▂▂▂▃▇█▄▁▁▃▃▂▂▃▄▃▆▄▄▃▅▆472.5541.7645.9572.2539.1639.0490.8511.3281.2217.0382.0153.5122.4109.9141.6124.9154.6159.8229.6188.4322.3156.9149.8197.5250.9238.0269.5264.2355.1837.71026.8535.774.1138.0304.6281.0210.3250.3380.6431.5367.8816.3432.3443.3378.7563.5708.8NANANA
us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents ▅▆█▇▆█▅▆▂▁▄472.5541.7645.9572.2539.1639.0490.8511.3281.2217.0382.0NANANA141.6NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:AccountsReceivableNetCurrent ▁▂▁▂▃▅▄▅▅▄▄▅▅▅▄▄▄▃▃▃▃▂▂▃▅▆▅▅▆▄▄▄▆▆▅▆▇▇▇▇█▆▄362.2423.9345.8388.0483.6593.4554.1596.7581.4565.1527.8588.3621.9606.4545.3525.9538.6504.6452.1454.0492.5442.4400.3497.5593.4690.9603.6623.7650.9557.5528.2576.9655.5681.5613.3685.7744.3753.1709.1769.3808.1694.0545.4NANANA392.0NANANA
us-gaap:InventoryNet ▂▂▁▂▂▃▃▃▄▄▄▄▄▄▃▂▂▂▂▂▂▃▅▆▇▇▇▆▆▆▅▆███▇██▆▇▇▄▁1059.01047.8997.11035.91103.51181.11155.31168.51217.51254.41211.11239.81254.11210.81176.11101.11076.21051.91037.01078.91094.31166.31271.61356.11472.91472.61472.81417.71406.51408.51322.11344.91504.91537.51536.61460.21512.51511.41384.31434.51465.41231.91024.5NANANA825.5NANANA
us-gaap:InventoryFinishedGoods ▂▄▅▆▅▄▃▅▅▆▆▅▅▅▄▄▃▃▃▄▄▄▅▅▆▅▄▄▃▃▃▄▆▆▇▇██▆▆▆▂▁143.9164.0181.6191.1186.5171.7161.3180.9182.7192.4191.1190.0176.9181.2165.0164.8159.4160.0161.7169.4164.7164.7184.1190.0191.8177.0172.2165.5151.4161.3162.1164.7195.2196.6209.0214.4226.6219.8199.9191.3190.9143.3126.5NANANA96.1NANANA
us-gaap:InventoryLIFOReserve ▃▃▃▃▃▃▃▄▄▄▄▄▄▄▃▃▂▂▂▂▁▁▁▂▄▄▄▅▄▄▃▄▅▆▆▇▇██████-29.9-37.3-44.1-41.1-47.6-45.6-33.6-6.7-13.9-4.7-2.9-1.7-3.7-23.1-43.1-45.8-79.1-89.3-97.3-113.3-131.8-136.1-136.4-85.1-9.3-4.3-4.818.58.5-20.4-29.412.450.176.476.9124.5146.6153.7153.7159.6172.1166.9163.0NANANA102.8NANANA
us-gaap:InventoryRawMaterialsAndSupplies ▃▄▃▃▃▂▂▃▃▃▃▃▂▂▂▁▁▁▁▁▃▃▃▄▄▄▄▅▆▆▅▇███▆▅▄▃▄▄▃▂206.3224.1207.6210.5202.2174.8164.9199.6194.1212.5191.5204.3187.7175.7162.8157.4141.6148.8149.6157.0194.4207.5216.0235.0239.2234.5249.3262.1293.3291.2277.6330.7359.8367.6351.6287.6274.7242.9205.7231.1239.1191.4169.3NANANA158.3NANANA
us-gaap:OtherAssetsCurrent ▂▁▁▂▁▂▃▆█▅▄▅▄▅▂▂▁▂▂▂▂▁▂▂▃▃█▆▅▅▃▇▅▅▃▃▃▃▅▂▁▂▆50.538.038.348.533.851.064.3108.1140.492.774.689.280.286.152.752.230.746.347.840.843.335.145.947.566.364.1136.2109.497.786.967.6120.697.389.456.157.960.459.995.554.236.342.7112.9NANANA71.3NANANA
us-gaap:Land █████▇███▅▅▅▅▆▅▅▅▅▅▅▅▅▅▄▄▄▄▄▄▄▄▄▇▇█▇▇▇▇▇█▁▁34.934.834.835.034.934.234.634.434.631.631.531.631.631.931.731.731.531.531.431.730.730.931.030.330.430.030.230.030.230.130.229.934.134.034.434.334.034.234.034.134.526.025.8NANANA24.8NANANA
us-gaap:MachineryAndEquipmentGross ▁▁▁▇▇▆▇▆▆▆▆▆▆▆▆▆▆▆▅▆███▇▇▇▇▆▆▆▆▅▅▅▅▄▄▄▃▃▃▁▁2791.82768.42736.93721.73681.33656.43671.33612.13592.13653.03622.73646.03628.43618.13597.63562.63527.03521.53497.23646.83924.93906.33858.13792.43762.43714.63702.53668.93618.03572.53526.03431.93478.93377.73344.43264.83222.93183.13146.23084.23048.32766.42750.8NANANA2607.8NANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
us-gaap:PropertyPlantAndEquipmentGross ▁▁▁▆▆▆▆▆▆▆▆▆▆▆▆▆▅▅▅▆███▇▇▇▇▇▇▆▆▅▆▅▅▄▄▄▃▃▃▂▁3401.33372.73336.44640.94593.04552.44538.64467.84444.64538.54505.94528.74509.64499.14473.84437.24398.84383.84358.24525.85026.34998.84937.34870.94844.04797.74781.64734.34680.64625.44575.34409.14483.84346.24299.84169.44087.34007.43937.23837.43788.13459.43414.8NANANA3223.2NANANA
us-gaap:ConstructionInProgressGross ▆█▃▁244.9252.6233.4223.1NANA177.3NANANA83.7NANANA90.7NANANA87.4NANANA119.6NANANA71.1NANANA186.2NANANA601.6NANANA346.2NANANA184.5NANANA270.6NANANA
us-gaap:AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment ▆▅▅██▇▇▇▇▇▇▇▇▆▆▆▅▅▅▆▇▇▆▆▅▅▅▄▄▄▄▃▄▄▄▃▃▃▂▂▂▁▁1915.01894.01867.22174.32138.02106.92088.52060.32039.72067.82030.92056.12030.62008.41978.11946.31906.51888.01859.32011.42067.42036.72009.11932.71897.31854.01819.81797.21763.81736.11701.21664.41791.41749.01739.91687.11643.31609.31568.41529.91495.41460.21425.5NANANA1315.3NANANA
us-gaap:PropertyPlantAndEquipmentNet ▁▁▁▆▆▆▆▅▅▆▆▆▆▆▆▆▆▆▆▆███████████▇▇▆▆▆▆▅▅▅▅▃▃1486.31478.71469.22466.62455.02445.52450.12407.52404.92470.72475.02472.62479.02490.72495.72490.92492.32495.82498.92514.42958.92962.12928.22938.22946.72943.72961.82937.12916.82889.32874.12744.72692.42597.22559.92482.32444.02398.12368.82307.52292.71999.21989.3NANANA1907.9NANANA
us-gaap:Goodwill ▁▁▁▁▁▅▅▅▅▅▅▅▅▅▅▅▆▆▆▆▆▆▆███████▇▇▇▇▇▇▇▇▇▇▇▁▁241.9241.6240.7238.4236.4520.8525.8523.8524.8536.8534.7536.4531.0534.2531.4531.9643.5642.6641.9644.4646.9648.6651.4780.2781.5777.9780.4782.8785.1775.5727.9728.1737.0736.3740.1740.3737.7739.0737.7740.6690.6209.1206.8NANANA207.8NANANA
us-gaap:OtherAssetsNoncurrent ▃▃▄▄▄▆▇▄▇▅▃▄▄▄▃▃▃▃▄▄▅▅▅▆▇▇▇▇▇▇▆▇▇▇▇▇▇▇▇█▇▁▁249.3254.8259.0272.6276.4332.8355.7275.2358.2305.6245.4257.6257.0257.2242.6248.2250.4253.4262.7271.4302.8307.7304.5344.1357.6369.6358.3368.3352.0353.6342.0348.0358.4363.1365.7371.4370.8366.9370.9389.4374.6197.1182.4NANANA169.6NANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
us-gaap:AccountsPayableCurrent ▂▃▂▁▂▅▇▅▅▆▇▅▅▅▅▃▄▃▂▂▂▃▄▄▆██▆█▇▆▅▅▆▇▅▆▇▆▇▇▇▄265.8324.8290.6240.7275.8424.6521.2415.8420.6455.3498.8416.1429.3424.7420.1350.5355.5346.4294.3285.2308.2340.4380.8367.1487.5559.5556.7482.7556.3518.2471.8401.9445.6479.4499.9409.3451.7505.8490.7491.8503.6505.2394.1NANANA308.6NANANA
us-gaap:AccruedLiabilitiesCurrent ▁▂▂▁▂▁▃▃▄▂▄▂▂▁▅▅▅▅▆▆▅▅▆▇▇▅▇▆▆▆▆▆▆▅▇█▇▇▇▇█▄▃210.2230.0233.1213.0216.0209.6237.8238.3257.8220.4260.1228.7225.3205.3282.4286.7278.0276.4309.3310.9290.8291.3301.8329.8314.4288.8323.2305.7298.5294.9310.9304.9293.1280.0330.5336.7327.9324.5320.3315.8341.0270.8249.9NANANA258.8NANANA
us-gaap:ContractWithCustomerLiabilityCurrent ▇██▇▇█▆▇▅▆▅▅▅▅▁103.8118.7111.897.8109.8114.378.797.169.377.971.469.270.466.20.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:DebtCurrent ▁▁▁▁▁▆▁▁▁▁▁▁▁▂▁▂▂▄▃▁▁▄▁▁▁▁▁▁▁████▁▁▁▁▁▁▃▄▃▃19.315.717.812.212.8310.711.512.111.56.46.616.616.363.710.136.467.5172.8105.15.46.7156.53.94.018.317.917.817.517.4420.0419.9419.9420.317.117.116.827.328.427.3144.9154.2139.4141.4NANANA33.5NANANA
us-gaap:LiabilitiesCurrent ▁▂▂▁▂▆▄▃▃▃▄▃▃▃▃▂▂▃▂▁▁▄▂▃▄▅▅▄▄██▇▇▄▄▃▄▄▄▅▅▅▃599.1689.2653.3563.7614.41059.2849.2763.3759.2760.0836.9730.6741.3759.9712.6673.6701.0795.6708.7601.5605.7828.7686.5737.1888.0937.0959.9839.6903.01253.71211.01168.61186.6813.1871.5775.7823.5875.0861.8978.5998.8915.4791.0NANANA624.6NANANA
us-gaap:OtherLiabilitiesCurrent NANA233.1NANANA237.8NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
 us-gaap:LongTermDebt us-gaap:AdjustmentsForNewAccountingPronouncements,us-gaap:DebtInstrument,us-gaap:LongtermDebtType ati:AccountingStandardsUpdate202006,ati:AlleghenyTechnologiesConvertibleSeniorNotes35Due2025,us-gaap:ConvertibleDebtNANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:LongTermDebtAndCapitalLeaseObligations ▆▆▆▅▅▄▄▆▆▅▅▅▅▅▅██▇▇██▅▅▅▅▅▅▅▅▅▅▆▂▅▅▅▅▅▅▅▅▅▁1602.21598.41550.01529.01516.91390.01387.41541.71537.11536.21535.51535.31535.51535.31530.61877.71876.61772.51771.91870.41870.11492.71491.81501.61502.71509.11509.11509.11520.71526.81527.41542.21053.61462.01463.01462.51474.11481.51482.01483.41496.51422.5921.9NANANA1037.6NANANA
 us-gaap:PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent us-gaap:RetirementPlanType us-gaap:OtherPostretirementBenefitPlansDefinedBenefitNANA326.7NANANA312.5NANANA318.4NANANA317.8NANANA317.7NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent us-gaap:RetirementPlanType us-gaap:PensionPlansDefinedBenefitNANA673.6NANANA731.5NANANA730.0NANANA697.0NANANA827.9NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:MinorityInterest █▇▆▅▄▄▃▅▅▅▄▃▅▅▄▃▃▂▁▁▄▃▃▃▅▅▅▄▃▃▃▂▂▄▄▃▃▃▂▂▁▂▁133.1126.4120.3116.1107.0104.8103.1111.9112.2112.4105.9103.0116.9117.2105.199.7100.995.289.690.9104.9103.2101.699.8116.4113.4110.9108.4102.9100.8100.597.495.7109.6107.5102.6100.098.996.392.689.392.688.6NANANA77.4NANANA
us-gaap:OtherLiabilitiesNoncurrent █▇▇█▇▅▅▄▄▄▁▁▁▁▁▂▂▂▂▂▂▃▃▃▃▅▅▅▅▅▅▂▃▃▃▃▃▃▄▄▄▃▃220.1207.1189.9212.3206.9163.5160.8124.9124.3123.169.266.766.662.573.280.883.382.983.486.289.9106.8108.3112.2103.0162.0156.2149.3146.0148.6148.294.9100.5101.0109.9116.3117.5117.1124.7120.4127.5100.5100.6NANANA119.3NANANA
us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearTwo NANA16.6NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearThree NANA12.8NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFour NANA9.3NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFive NANA7.6NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive NANA18.1NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
us-gaap:StockholdersEquity ▁▁▁▅▅▆▆▆▅▅▅▅▅▅▅▄▄▄▄▄▅▅▆▇▇▇▇████▇▇▇▇▇▇▇▇█▇▆▆473.0482.9521.11733.71735.32087.82090.12168.02026.41934.21885.71980.21925.01846.11739.41347.81413.51394.21355.21471.81994.41995.22082.82405.72584.32594.62598.42871.22875.72866.32894.22466.72491.22487.12479.62642.32575.52515.02475.32748.72690.72110.52040.8NANANA2012.2NANANA
us-gaap:StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest ▁▁▁▅▅▆▆▆▅▅▅▅▅▅▅▃▄▄▃▄▅▅▆▇▇▇▇████▇▇▇▇▇▇▇▇█▇▆▅▅▅▅▅606.1609.3641.41849.81842.32192.62193.22279.92138.62046.61991.62083.22041.91963.31844.51447.51514.41489.41444.81562.72099.32098.42184.42505.52700.72708.02709.32979.62978.62967.12994.72564.12586.92596.72587.12744.92675.52613.92571.62841.32780.02203.12129.42132.72130.52098.52089.6NANANA
us-gaap:CommonStockValue ███████████████▃▃▃▃▃▃▃▃▃▃▃▃▃▃▃▃▃▃▃▃▃▃▃▃▃▃▁▁12.712.712.712.712.712.712.712.712.712.712.712.712.712.712.711.011.011.011.011.011.011.011.011.011.011.011.011.011.011.011.011.011.011.011.011.011.011.011.011.011.010.210.2NANANA10.2NANANA
us-gaap:AdditionalPaidInCapitalCommonStock ███████████████▅▅▅▅▅▅▅▅▅▅▅▅▅▅▅▅▅▅▅▅▅▅▅▅▅▅▁▁1587.51580.51625.51622.21617.81592.11618.01612.11604.61599.71615.41608.51604.11599.51596.31196.41191.31187.11188.81183.31178.11171.91161.71158.81154.91154.21164.21161.91156.61160.21185.91181.21175.11168.51181.71183.41169.71161.41207.11188.21176.2653.6658.9NANANA653.6NANANA
us-gaap:RetainedEarningsAccumulatedDeficit ▁▁▁▄▅▆▆▆▅▅▅▅▅▄▄▄▅▅▅▄▆▆▆▇████████████████▇▇▇53.8103.0106.51227.41277.61700.41679.31622.81511.81437.01422.01380.91330.41257.81184.31182.61303.81294.61277.11267.11806.71835.91945.92181.72346.32382.42398.92396.42416.52440.72490.12335.92389.12404.92427.62443.62429.82394.92361.52349.72307.32264.42224.8NANANA2230.5NANANA
us-gaap:AccumulatedOtherComprehensiveIncomeLossNetOfTax ▂▁▁▂▂▁▁▃▃▃▂▄▄▄▃▃▃▃▃▄▄▄▃▅▅▄▄██▇▇▄▄▃▃▅▅▅▄████-1176.3-1208.6-1223.6-1128.6-1172.8-1216.6-1201.7-1061.4-1084.4-1095.5-1133.8-991.3-991.6-992.2-1027.8-1016.3-1067.2-1071.4-1093.7-961.7-973.7-994.9-1014.5-925.4-907.3-930.8-931.4-653.6-664.2-694.3-713.2-982.6-1004.8-1016.2-1029.4-875.9-912.4-925.7-941.6-637.3-639.6-649.0-665.1NANANA-673.5NANANA
 us-gaap:AccumulatedOtherComprehensiveIncomeLossNetOfTax us-gaap:StatementEquityComponents ati:AccumulatedDeferredTaxAssetValuationAllowance▃▂▁▄▃▂▂▄▃▂▁▆▅▅▄▄▂▂▂████-38.7-45.4-50.3-26.4-32.8-41.5-41.5-29.3-38.0-41.6-49.3-17.5-18.7-24.4-28.8-29.3-45.6-40.4-45.60.00.00.00.0NANANA0.0NANANA0.0NANANANANANANANANANANANANANANANANANANA
 us-gaap:AccumulatedOtherComprehensiveIncomeLossNetOfTax us-gaap:StatementEquityComponents us-gaap:AccumulatedDefinedBenefitPlansAdjustment▂▁▁▂▂▂▂▄▃▃▃▄▄▄▄▄▄▄▃▄▄▄▄▅▄▄▄███▇▃▃▃▂-1086.9-1103.4-1119.9-1036.2-1051.8-1067.4-1083.1-957.3-973.4-989.7-1005.8-912.2-926.2-940.2-954.5-933.0-943.5-954.7-965.5-902.3-913.7-925.1-951.2-894.0-906.5-919.0-931.5-678.6-692.0-705.5-718.9-975.2-993.5-1011.8-1030.0NANANANANANANANANANANANANANANA
 us-gaap:AccumulatedOtherComprehensiveIncomeLossNetOfTax us-gaap:StatementEquityComponents us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedges▅▄▄▄▃▃▄▅▄▅▃▄▆▅▅▄▃▄▄▄▄▁▁▄▇█▆▇▅▃▂▂▃▅▃5.11.12.11.3-3.7-8.5-0.59.90.03.9-4.83.113.29.29.0-0.8-5.70.32.43.2-0.2-18.3-15.7-0.218.326.016.320.65.0-2.6-9.6-12.2-3.75.7-2.7NANANANANANANANANANANANANANANA
 us-gaap:AccumulatedOtherComprehensiveIncomeLossNetOfTax us-gaap:StatementEquityComponents us-gaap:AccumulatedTranslationAdjustment▃▃▄▃▂▁▂▂▃▃▂▃▃▅▄▄▃▂▂▃▃▄▄▅▆▅▆▇█▇█▇▆▆▇-55.8-60.9-55.5-67.3-84.5-99.2-76.6-84.7-73.0-68.1-73.9-64.7-59.9-36.8-53.5-53.2-72.4-76.6-85.0-62.6-59.8-51.5-47.6-31.1-19.0-37.8-16.24.322.713.815.34.8-7.5-10.13.4NANANANANANANANANANANANANANANA
us-gaap:TreasuryStockValue ▄▄4.74.7NANA0.00.818.218.218.319.730.630.630.631.726.125.925.427.128.027.927.728.721.320.420.622.244.344.544.251.379.678.879.281.1111.3119.8122.6126.6162.7162.9164.2168.7188.0NANANA208.6NANANA
us-gaap:MinorityInterest █▇▆▅▄▄▃▅▅▅▄▃▅▅▄▃▃▂▁▁▄▃▃▃▅▅▅▄▃▃▃▂▂▄▄▃▃▃▂▂▁▂▁133.1126.4120.3116.1107.0104.8103.1111.9112.2112.4105.9103.0116.9117.2105.199.7100.995.289.690.9104.9103.2101.699.8116.4113.4110.9108.4102.9100.8100.597.495.7109.6107.5102.6100.098.996.392.689.392.688.6NANANA77.4NANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
us-gaap:NetCashProvidedByUsedInOperatingActivities ▃▂▅▄▅▁▇▅▄▁█▅▅▂▅▄▄▁▄▂▄▂▄▄▅▃▅▃▄▂▆▆▅▂▆▆▅▃▇▆▃▂▅▅▁▂-34.5-68.1121.959.4101.0-115.4240.194.425.6-130.0276.281.682.1-47.176.231.724.7-110.268.0-78.127.9-61.522.517.479.512.094.1-0.719.4-56.9141.0169.4115.4-57.4181.7186.078.0-18.2189.3179.5-21.7-50.391.0129.5-121.4-72.0NANANANA
us-gaap:NetCashProvidedByUsedInInvestingActivities ▄▄▄▄▄▄▄▆▅▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄█▃▃▄▃▄▄▄▄▄▁▄▄▄▄▄-33.7-25.1-39.499999999999986-27.4-36.6-25.2-67.7138.035.0-23.6-36.0-39.3-28.3-41.5-37.5-30.1-29.8-22.2-27.2-29.3-74.8-68.7-45.1-36.2-41.3-22.5-68.1-59.8-79.4-108.9383.7-171.5-137.0-86.2-134.6-79.3-95.8-69.0-109.7-70.7-402.6-41.7-84.4-35.8-46.0-50.6NANANANA
us-gaap:NetCashProvidedByUsedInFinancingActivities ▄▄▄▄▃▇▃▄▄▄▄▄▄▅▄▄▄▅▄▄▆▅▄▄▄▄▄▄▁▄▄█▄▄▄▄▄▄▃▄▄█▄▄▄▄-1.0-11.0-8.71.1-164.3288.8-192.9-2.33.6-11.4-11.7-11.2-41.356.9-22.0-31.3-0.162.60.4-26.5212.3137.3-25.1-34.6-25.3-21.0-20.7-30.4-422.6-23.3-33.6463.7-42.3-23.0-23.5-36.0-22.2-43.1-130.5-45.1-24.2476.0-17.6-29.1-17.4-22.7NANANANA
us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect ▃▂▅▅▂▇▄█▅▁-69.2-104.273.733.1-99.9148.2-20.500000000000014230.164.2-165.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
 us-gaap:AmortizationOfFinancingCosts us-gaap:DebtInstrument,us-gaap:LongtermDebtType ati:AlleghenyTechnologiesConvertibleSeniorNotes35Due2025,us-gaap:ConvertibleDebt0.4NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:AmortizationOfFinancingCosts us-gaap:DebtInstrument,us-gaap:LongtermDebtType ati:AlleghenyTechnologiesConvertibleSeniorNotes4.75Due2022,us-gaap:ConvertibleDebt0.1NANANA0.4NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:DepreciationDepletionAndAmortization ▂▂▁▁▁▂▂▂▃▃▃▃▃▄▄▄▄▄▄▅▅▆█▇█▆▆▆▅▆▇▇██████▇▇▅▂▁▂▁▁36.336.135.035.435.637.336.537.038.938.739.338.438.939.840.140.140.340.340.142.443.744.148.547.848.045.645.244.143.544.046.446.648.448.548.948.948.248.047.246.643.237.435.536.235.234.6NANANANA
us-gaap:IncreaseDecreaseInAccountsReceivable ▂▆▃▁▁▅▃▄▅▅▂▃▄▆▄▄▅▅▄▃▅▅▁▁▁▆▃▃▆▅▃▃▃▆▂▂▄▅▂▃▅█▂▅▇▆-61.778.1-42.2-95.7-109.739.2-40.414.840.437.3-59.0-33.815.161.719.4-12.734.052.5-1.9-38.550.042.2-97.2-95.9-97.587.3-19.6-29.891.128.6-52.3-31.0-26.068.2-72.4-58.5-8.944.0-60.1-38.829.1148.6-77.653.796.880.5NANANANA
us-gaap:IncreaseDecreaseInInventories ▄▅▃▂▂▄▃▂▃▄▃▃▄▆▅▄▄▄▃▃▂▁▂▁▄▄▅▄▃▅▃▁▃▄▅▂▄▆▂▃▆█▄▃▅▇11.150.8-38.9-67.5-77.625.8-13.2-48.8-6.743.3-28.7-14.643.4108.475.124.924.314.9-42.0-15.4-72.0-105.3-84.5-116.80.4-0.355.110.6-4.682.6-19.9-95.1-32.50.976.4-52.41.2127.1-50.3-30.2100.4207.412.5-40.981.8145.6NANANANA
us-gaap:IncreaseDecreaseInOtherOperatingCapitalNet ▆▄▁▅▃▅▄▄▅█▃▇▄█▄▅▄▇▆▄▅▅▆▅▃▇▅▆▄▆▁▃▄█▄▄▄▅▆▆▄▂▇▃▆▆19.6-11.2-70.0-4.6-42.6-2.4-13.3-25.6-6.344.6-43.337.2-21.343.9-11.9-4.8-17.624.213.2-17.43.20.417.54.3-32.830.03.19.8-26.39.3-62.2-43.0-20.948.7-18.5-18.0-22.5-5.119.217.9-26.2-51.633.1-31.58.120.8NANANANA
us-gaap:NetCashProvidedByUsedInOperatingActivities ▃▂▅▄▅▁▇▅▄▁█▅▅▂▅▄▄▁▄▂▄▂▄▄▅▃▅▃▄▂▆▆▅▂▆▆▅▃▇▆▃▂▅▅▁▂-34.5-68.1121.959.4101.0-115.4240.194.425.6-130.0276.281.682.1-47.176.231.724.7-110.268.0-78.127.9-61.522.517.479.512.094.1-0.719.4-56.9141.0169.4115.4-57.4181.7186.078.0-18.2189.3179.5-21.7-50.391.0129.5-121.4-72.0NANANANA
us-gaap:NetIncomeLoss ▇▇▁▇▅▇▇█▇▇▇▇▇▇▇▆▇▇▇▄▇▇▆▆▇▇▇▇▇▇█▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇-49.2-7.9-1121.0-50.1-422.621.156.5111.075.115.041.150.572.858.01.7-121.210.117.59.9-530.8-18.8-101.2-226.9-144.6-16.410.022.1-0.7-4.0-20.0173.4-33.84.410.010.535.356.456.231.762.364.056.315.11.036.418.237.81.4-13.45.9
us-gaap:ProfitLoss ▇▇▁▇▅▇▇█▇▇▇▇▇▇▇▆▇▇▇▄▇▇▆▆▇▇▇▇▇▇█▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇-44.4-2.4-1116.3-47.0-419.923.660.0115.378.516.345.055.675.660.55.2-119.413.421.113.7-527.2-15.5-98.1-223.3-141.3-13.912.625.32.9-0.7-17.9175.6-32.26.611.613.537.358.758.334.264.266.058.717.43.338.219.8NANANANA
 us-gaap:ProfitLoss us-gaap:StatementEquityComponents us-gaap:NoncontrollingInterest▇█▇▄▃▃▅▆▄▁▅▇▃▃▅▂▄▅▅▅▄▄▅▄▃▃4.85.54.6999999999999993.12.72.53.54.33.41.33.95.12.82.53.51.83.33.63.83.63.33.13.63.32.52.6NANA3.32.12.21.62.21.63.02.02.32.12.51.92.02.42.32.31.81.6NANANANA
 us-gaap:ProfitLoss us-gaap:StatementEquityComponents us-gaap:RetainedEarnings▇▇▁▇▅▇▇█▇▇▇▇▇▇▇▆▇▇▇▄▇▇▆▆▇▇▇▇▇▇█▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇-49.2-7.9-1121.0-50.1-422.621.156.5111.075.115.041.150.572.858.01.7-121.210.117.59.9-530.8-18.8-101.2-226.9-144.6-16.410.022.1-0.7-4.0-20.0173.4-33.84.410.010.535.356.456.231.762.364.056.315.11.036.418.2NANANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
us-gaap:NetCashProvidedByUsedInInvestingActivities ▄▄▄▄▄▄▄▆▅▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄█▃▃▄▃▄▄▄▄▄▁▄▄▄▄▄-33.7-25.1-39.499999999999986-27.4-36.6-25.2-67.7138.035.0-23.6-36.0-39.3-28.3-41.5-37.5-30.1-29.8-22.2-27.2-29.3-74.8-68.7-45.1-36.2-41.3-22.5-68.1-59.8-79.4-108.9383.7-171.5-137.0-86.2-134.6-79.3-95.8-69.0-109.7-70.7-402.6-41.7-84.4-35.8-46.0-50.6NANANANA
us-gaap:PaymentsToAcquireProductiveAssets ▁▁▂▁▂▁▃▂▁▁▂▁▁▂▂▁▁▁▁▁▃▃▂▁▂▁▃▂▂▂█▆▅▃▅▃▄▃▄▃▂▂▃▁▂▂35.026.441.928.636.929.170.146.827.823.537.930.729.041.637.430.030.524.827.329.675.869.545.036.240.722.668.259.658.339.6217.2171.8136.886.9136.479.995.869.9109.471.155.542.285.935.646.451.2NANANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
us-gaap:NetCashProvidedByUsedInFinancingActivities ▄▄▄▄▃▇▃▄▄▄▄▄▄▅▄▄▄▅▄▄▆▅▄▄▄▄▄▄▁▄▄█▄▄▄▄▄▄▃▄▄█▄▄▄▄-1.0-11.0-8.71.1-164.3288.8-192.9-2.33.6-11.4-11.7-11.2-41.356.9-22.0-31.3-0.162.60.4-26.5212.3137.3-25.1-34.6-25.3-21.0-20.7-30.4-422.6-23.3-33.6463.7-42.3-23.0-23.5-36.0-22.2-43.1-130.5-45.1-24.2476.0-17.6-29.1-17.4-22.7NANANANA
us-gaap:ProceedsFromIssuanceOfLongTermDebt NANA0.06.4NANANANANANANANANANANANANANA0.00.0NANANANANANA0.0NANANA0.0NANANA0.00.00.00.00.00.00.0500.00.00.00.00.0NANANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
 us-gaap:DebtInstrumentInterestRateStatedPercentage us-gaap:DebtInstrument ati:AlleghenyTechnologiesConvertibleSeniorNotes4.75Due2022NANA4.75e-06NANA4.75e-084.75e-084.75e-084.75e-084.75e-084.75e-084.75e-084.75e-084.75e-084.75e-084.75e-084.75e-084.75e-084.75e-084.75e-084.75e-08NANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:DebtInstrumentInterestRateStatedPercentage us-gaap:DebtInstrument,us-gaap:LongtermDebtType ati:AlleghenyTechnologiesConvertibleSeniorNotes35Due2025,us-gaap:ConvertibleDebt████▁3.5e-063.5e-063.5e-063.5e-063.5e-08NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA

Common Stock Value

us-gaap:CommonStockValue

us-gaap:CommonStockValue


Common
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value1212121212121212121212121212121111111111111111111111111111111111111111111111111111101010
Percentage of CommonStockValue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.30.30.30.30.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.2

Weighted Average Number Of Diluted Shares Outstanding

us-gaap:WeightedAverageNumberOfDilutedSharesOutstanding

us-gaap:WeightedAverageNumberOfDilutedSharesOutstanding


Weighted
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-09-302012-06-302012-03-312011-09-302011-06-302011-03-312010-09-302010-06-302010-03-31
Value1271261261261461461461261461451451071281281071071071071071081081071071061071071161161161161131099810898
Percentage of WeightedAverageNumberOfDilutedSharesOutstanding100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Weighted Average Number Of Shares Outstanding Basic

us-gaap:WeightedAverageNumberOfSharesOutstandingBasic

us-gaap:WeightedAverageNumberOfSharesOutstandingBasic


Weighted
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
Value127126126126126126126125125125125125125125118107107107108107107107109107107107108107107107107106106106107106106105106105102979898989898989897
Percentage of WeightedAverageNumberOfSharesOutstandingBasic100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount

us-gaap:AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount

us-gaap:AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount


Antidilutive
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-09-302012-06-302012-03-31
Value252525200.00.00.0190.00.00.0200.00.0219.30.80.81.20.00.07.010.010.09.69.60.00.00.0
Percentage of AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount100.0100.0100.0100.00.00.00.0100.00.00.00.0100.00.00.0100.0100.0100.0100.0100.00.00.0100.0100.0100.0100.0100.00.00.00.0

Earnings Per Share Basic

us-gaap:EarningsPerShareBasic

us-gaap:EarningsPerShareBasic


Earnings
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
Value-0.39-0.06-8.85-0.4-3.340.170.450.880.60.120.330.40.580.460.01-1.120.090.160.09-4.95-0.18-0.94-2.12-1.35-0.150.090.2-0.01-0.03-0.191.62-0.320.040.090.10.330.530.530.30.590.630.580.160.010.370.190.390.01-0.140.06
Percentage of EarningsPerShareBasic100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Earnings Per Share Diluted

us-gaap:EarningsPerShareDiluted

us-gaap:EarningsPerShareDiluted


Earnings
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
Value-0.39-0.06-8.85-0.4-3.340.160.410.780.540.120.30.370.520.420.01-1.120.090.160.09-4.95-0.18-0.94-2.12-1.35-0.150.090.2-0.01-0.03-0.191.62-0.320.040.090.10.320.50.50.290.560.590.540.150.010.360.180.360.01-0.140.06
Percentage of EarningsPerShareDiluted100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Income Loss From Continuing Operations Per Basic Share

us-gaap:IncomeLossFromContinuingOperationsPerBasicShare

us-gaap:IncomeLossFromContinuingOperationsPerBasicShare


Income
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
Value-0.39-0.06-8.86-0.4-3.340.170.450.880.60.120.330.40.580.460.04-1.120.090.160.1-4.95-0.18-0.94-2.12-1.35-0.150.090.180-0.03-0.17-0.79-0.270.040.090.150.30.480.49
Percentage of IncomeLossFromContinuingOperationsPerBasicShare100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Income Loss From Continuing Operations Per Diluted Share

us-gaap:IncomeLossFromContinuingOperationsPerDilutedShare

us-gaap:IncomeLossFromContinuingOperationsPerDilutedShare


Income
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
Value-0.39-0.06-8.86-0.4-3.340.160.410.780.540.120.30.370.520.420.04-1.120.090.160.1-4.95-0.18-0.94-2.12-1.35-0.150.090.180-0.03-0.17-0.79-0.270.040.090.150.290.460.46
Percentage of IncomeLossFromContinuingOperationsPerDilutedShare100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Comprehensive Income Net Of Tax

us-gaap:ComprehensiveIncomeNetOfTax

us-gaap:ComprehensiveIncomeNetOfTax


Comprehensive
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value-16.97.1-1216.0-5.9-378.86.2-83.81348653-101.4507393-9.8-70.31439-122.1-518.82.4-81.6-316.0-162.77.110-255.79.926-1.0442-11.61523-143.0716972-272.6647372
Percentage of ComprehensiveIncomeNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-2.71.0-184.7-1.0-49.20.6-8.213.28.05.3-9.85.07.39.6-1.1-8.11.64.6-15.3-67.30.3-10.8-42.8-19.50.70.9-24.40.92.3-0.148.4-1.21.42.0-14.05.95.15.3-21.84.85.45.9

Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest

us-gaap:ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest

us-gaap:ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest


Comprehensive
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
Value6.76.1119.12.21.75.2-0.3-0.26.52.9-3.9-0.39.43.96.83.55.6-1.32.01.81.61.8-0.83.02.42.35.42.20.23.11.74.12.14.92.61.12.7
Percentage of ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax1.10.91.71.50.30.20.5-0.0-0.00.60.3-0.4-0.01.00.40.80.40.6-0.20.30.20.20.2-0.10.30.20.20.50.20.00.30.20.40.20.50.20.10.2

Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest

us-gaap:ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest

us-gaap:ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest


Comprehensive
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-10.213-1204.63.2-376.67.9-78.61338659-98.54673103-5.9-63.51745-123.4-516.84.2-80.0-314.2-163.51013-253.41528-0.8445-9.91925-138.1747074-269.06877768.0134919
Percentage of ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-1.71.9-183.00.5-48.90.8-7.713.18.06.0-9.54.67.210.5-0.6-7.32.05.2-15.5-67.10.5-10.6-42.5-19.61.01.2-24.21.42.5-0.148.7-1.01.82.1-13.56.15.25.5-21.55.05.76.20.81.34.72.2

Cost Of Goods And Services Sold

us-gaap:CostOfGoodsAndServicesSold

us-gaap:CostOfGoodsAndServicesSold


Cost
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-30
Value573606613559695820849859902873890859835830767763755
Percentage of CostOfGoodsAndServicesSold100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax93.187.693.193.690.385.983.484.383.687.085.884.382.884.884.387.985.9

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

ati:NickelAndOtherRawMaterialContracts, us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedges


Cost
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-30
Value-1.4-2.0-0.9-0.92.30.3-4.4-1.50.30.50.2-2.2-4.5-3.7-0.61.51.6
Percentage of CostOfGoodsAndServicesSold-0.2-0.3-0.1-0.20.30.0-0.5-0.20.00.10.0-0.3-0.5-0.4-0.10.20.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-0.2-0.3-0.1-0.20.30.0-0.4-0.10.00.00.0-0.2-0.4-0.4-0.10.20.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax ati:NickelAndOtherRawMaterialContracts us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedges0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

srt:NaturalGasReserves, us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedges


Cost
Period End2021-06-302020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-30
Value-0.31.11.31.30.80.1-0.10.00.10.41.11.1
Percentage of CostOfGoodsAndServicesSold-0.10.20.20.20.10.0-0.00.00.00.00.10.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-0.00.20.20.10.10.0-0.00.00.00.00.10.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax srt:NaturalGasReserves us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedges0.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:ForeignExchangeContract, us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedges


Cost
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-30
Value0.00.00.10.0-0.7-0.40.00.4-0.8-0.5-0.30.3-3.9-3.8-4.1
Percentage of CostOfGoodsAndServicesSold0.00.00.00.0-0.1-0.00.00.0-0.1-0.1-0.00.0-0.5-0.5-0.5
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.00.00.00.0-0.1-0.00.00.0-0.1-0.0-0.00.0-0.4-0.4-0.5
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ForeignExchangeContract us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedges0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Gains Losses On Extinguishment Of Debt

us-gaap:GainsLossesOnExtinguishmentOfDebt

us-gaap:GainsLossesOnExtinguishmentOfDebt


Gains
Period End2020-12-312020-09-302020-06-302019-12-312019-06-302017-12-312011-03-312010-03-31
Value00-21500000.0-21600000.00-37000000.000
Percentage of GainsLossesOnExtinguishmentOfDebt0.00.0100.0100.00.0100.00.00.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.00.0-2.8-2.10.0-4.10.00.0

Gross Profit

us-gaap:GrossProfit

us-gaap:GrossProfit


Gross
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
Value428545387413416915917713114716017314813093112112975048-33.2-97.5-28.77710912197897011538710012416219820716921522320512789151121158947580
Percentage of GrossProfit100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax6.912.46.96.49.714.116.615.716.413.014.215.717.215.214.410.712.813.012.26.55.9-4.4-13.2-3.47.59.711.69.18.07.11.25.57.78.512.213.314.715.313.516.016.516.712.38.514.413.519.413.510.69.7

Income Loss From Continuing Operations

us-gaap:IncomeLossFromContinuingOperations

us-gaap:IncomeLossFromContinuingOperations


Income
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
Value-49.2-7.9-1121.0-50.1-422.621561117515415072581.7-121.210179.9-530.8-18.8-101.2-226.9-144.6-16.410.0190.0-3.8-18.1-83.8-28.43.79.716315151
Percentage of IncomeLossFromContinuingOperations100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-8.0-1.1-170.3-8.4-54.92.25.510.97.01.54.05.07.25.90.2-13.91.12.01.2-68.9-2.3-13.4-30.7-17.4-1.60.91.90.0-0.3-1.8-9.2-2.90.30.81.62.63.83.8

Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest

us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest

us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest


Income
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value-40.43.1-1142.8-46.2-327.334211198417396280650.4-121.31123
Percentage of IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-6.60.4-173.6-7.7-42.53.62.111.77.81.73.86.18.06.70.0-14.01.32.7

Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments

us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments

us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments


Income
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value-40.43.1-46.2-327.3341198417628065-121.31123-531.5-41.4-132.3-359.1-117.9-21.620264.1-3.4-26.0-140.8-35.37.71516548984499510093229.56033
Percentage of IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-6.60.4-7.7-42.53.611.77.81.76.18.06.7-14.01.32.7-69.0-5.1-17.5-48.6-14.2-2.11.82.60.4-0.3-2.6-15.4-3.60.71.31.64.46.66.24.07.17.47.62.20.95.83.7

us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:StatementEquityComponents

us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:AccumulatedDefinedBenefitPlansAdjustment


Income
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-31
Value-21.7-21.7-20.5-20.5-20.6-21.2-21.2-21.1-18.5-18.5-18.6-17.4-17.6-17.4-18.3-18.3-19.6-20.3-20.2-20.2-21.9-21.9-21.8-29.7-29.7-29.7
Percentage of IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments53.7-700.044.46.3-59.9-17.8-25.1-123.4-29.6-23.0-28.414.3-155.8-75.33.444.214.817.293.5-98.1-534.1644.183.884.1-385.7-194.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-3.5-3.1-3.4-2.7-2.2-2.1-2.0-2.1-1.8-1.8-1.9-2.0-2.0-2.0-2.4-2.3-2.6-2.4-2.0-1.8-2.0-2.0-2.2-3.1-2.6-2.5
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome us-gaap:AccumulatedDefinedBenefitPlansAdjustment0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedges


Income
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-31
Value1.51.7-0.4-4.2-1.80.8-0.5-0.92.64.73.01.21.40.9-0.6-2.9-5.03.32.12.72.60.5-2.1-4.3-0.5-0.7
Percentage of IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments-3.754.80.91.3-5.20.7-0.6-5.34.25.84.6-1.012.43.90.17.03.8-2.8-9.713.163.4-14.78.112.2-6.5-4.6
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.20.2-0.1-0.5-0.20.1-0.0-0.10.30.50.30.10.20.1-0.1-0.4-0.70.40.20.20.20.0-0.2-0.4-0.0-0.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedges0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest

us-gaap:IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:StatementEquityComponents

us-gaap:IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest

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-16.5-16.5-15.6-15.6-15.6-15.7-15.8-16.1-16.3-16.1-13.6-14.0-14.0-14.3-11.0-10.5-11.2-10.8-11.3-11.4-11.4-12.2-12.4-12.5-12.5-12.5-13.5-13.4-13.5-13.4-15.2-18.3-18.3-18.2
Percentage of IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-2.7-2.4-2.4-2.6-2.0-1.6-1.6-1.6-1.5-1.6-1.3-1.4-1.4-1.5-1.2-1.2-1.3-1.2-1.4-1.5-1.4-1.6-1.7-1.5-1.2-1.1-1.3-1.3-1.2-1.4-1.7-1.9-1.6-1.5
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:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedges


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
Value1.11.30.3-0.3-3.2-1.43.50.7-0.4-0.71.12.03.52.32.30.80.80.60.4-0.4-1.8-3.16.32.01.31.71.61.60.3-1.3-5.2-2.6-0.4-0.4
Percentage of IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest-6.7-7.9-1.91.920.58.9-22.2-4.32.54.3-8.1-14.3-25.0-16.1-20.9-7.6-7.1-5.6-3.53.515.825.4-50.8-16.0-10.4-13.6-11.9-11.9-2.29.734.214.22.22.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.20.20.0-0.1-0.4-0.10.30.1-0.0-0.10.10.20.30.20.30.10.10.10.1-0.1-0.2-0.40.90.20.10.20.20.10.0-0.1-0.6-0.3-0.0-0.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedges0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

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
Value4.05.5-26.50.89210-38.83.75.80.8-5.86.94.95.0-4.8-1.9-2.12.0-42.5-4.3-25.9-34.2-135.823-7.78.03.70.5-2.9-10.0102-8.51.13.72.6163125153134355.26.22213
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 RevenueFromContractWithCustomerExcludingAssessedTax0.60.8-4.00.112.01.1-3.80.40.50.1-0.60.70.50.5-0.5-0.2-0.20.2-5.3-0.6-3.2-4.5-18.42.8-0.80.70.40.0-0.3-1.011.2-0.90.10.30.31.42.31.91.32.32.52.90.50.62.11.5

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-5.2-5.2-5.0-4.9-4.9-4.9-5.3-5.1-4.9-5.0-4.7-4.5-4.5-4.3-6.6-6.9-6.4-6.6-7.1-6.9-6.9-7.4-8.1-7.8-7.7-7.7-8.3-8.5-8.4-8.4-9.5-11.4-11.4-11.5
Percentage of IncomeTaxExpenseBenefit-130.0-94.518.9-612.5-5.3-45.413.7-137.8-84.5-625.081.0-65.2-91.8-86.0137.5363.2304.8-330.016.7160.526.621.66.0-33.3100.0-96.2-224.3-1700.0289.784.0-9.3134.1-1036.4-310.8
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-0.8-0.8-0.8-0.8-0.6-0.5-0.5-0.5-0.5-0.5-0.5-0.4-0.4-0.4-0.7-0.8-0.7-0.8-0.9-0.9-0.9-1.0-1.1-0.9-0.8-0.7-0.8-0.8-0.8-0.9-1.0-1.2-1.0-1.0
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:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedges


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
Value0.40.40.1-0.1-1.0-0.41.20.1-0.1-0.20.30.61.20.71.40.40.60.30.2-0.2-1.1-1.93.81.30.81.01.01.00.2-0.8-3.3-1.7-0.1-0.3
Percentage of IncomeTaxExpenseBenefit10.07.3-0.4-12.5-1.1-3.7-3.12.7-1.7-25.0-5.28.724.514.0-29.2-21.1-28.615.0-0.54.74.25.6-2.85.6-10.412.527.0200.0-6.98.0-3.220.0-9.1-8.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.10.10.0-0.0-0.1-0.00.10.0-0.0-0.00.00.10.10.10.20.00.10.00.0-0.0-0.1-0.30.50.20.10.10.10.10.0-0.1-0.4-0.2-0.0-0.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedges0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:IncomeTaxExpenseBenefit us-gaap:StatementScenario, us-gaap:CollectiveBargainingArrangement

srt:ScenarioForecast, us-gaap:CollectiveBargainingArrangementOther


Income
Period End2021-09-30
Value15
Percentage of IncomeTaxExpenseBenefit0.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax srt:ScenarioForecast us-gaap:CollectiveBargainingArrangementOther0.0

Interest Expense

us-gaap:InterestExpense us-gaap:DerivativeInstrumentRisk, us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:StatementEquityComponents

us-gaap:InterestExpense

us-gaap:InterestRateSwap, us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedges


Interest
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value200000.0300000.0500000.0200000.0500000.0200000.00300000.0100000.0100000.0200000.0100000.00000
Percentage of InterestExpense100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.00.00.00.00.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.00.00.10.00.10.00.00.00.00.00.00.00.00.00.00.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:InterestRateSwap us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedges0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Net Income Loss

us-gaap:NetIncomeLoss

us-gaap:NetIncomeLoss


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
Value-49.2-7.9-1121.0-50.1-422.621561117515415072581.7-121.210179.9-530.8-18.8-101.2-226.9-144.6-16.410.022-0.7-4.0-20.0173-33.84.410.01035565631626456151.03618371.4-13.45.9
Percentage of NetIncomeLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-8.0-1.1-170.3-8.4-54.92.25.510.97.01.54.05.07.25.90.2-13.91.12.01.2-68.9-2.3-13.4-30.7-17.4-1.60.92.1-0.1-0.4-2.018.9-3.50.40.81.02.94.24.22.54.64.74.61.50.13.52.04.60.2-1.90.7

Net Income Loss Attributable To Noncontrolling Interest

us-gaap:NetIncomeLossAttributableToNoncontrollingInterest

us-gaap:NetIncomeLossAttributableToNoncontrollingInterest


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
Value4.85.54.6999999999999993.12.72.53.54.33.41.33.95.12.82.53.51.83.33.63.83.63.33.13.63.32.52.63.23.63.32.12.21.62.21.63.02.02.32.12.51.92.02.42.32.31.81.6
Percentage of NetIncomeLossAttributableToNoncontrollingInterest100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.80.80.70.50.40.30.30.40.30.10.40.50.30.30.40.20.40.40.50.50.40.40.50.40.20.20.30.30.30.20.20.20.20.10.30.20.20.20.20.10.10.20.20.20.20.2

Net Income Loss Available To Common Stockholders Diluted

us-gaap:NetIncomeLossAvailableToCommonStockholdersDiluted

us-gaap:NetIncomeLossAvailableToCommonStockholdersDiluted


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-49.2-7.9-1121.0-50.1-422.623591147815445376611.7-121.211209.9-530.8-18.8-101.2-226.9-144.8-16.49.9190.0-3.8-18.1-83.8-28.44.410.01237585834646658151.03818
Percentage of NetIncomeLossAvailableToCommonStockholdersDiluted100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-8.0-1.1-170.3-8.4-54.92.45.911.27.21.54.35.37.56.30.2-13.91.42.41.2-68.9-2.3-13.4-30.7-17.4-1.60.91.90.0-0.3-1.8-9.2-2.90.40.81.23.14.34.32.74.84.94.81.50.13.72.0

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
Value-11.331-1088.1-9.6-273.46898941106374941118168-87.345533.4-498.9-12.1-104.8-329.2-91.24.6465128232.5-122.5-17.5212832711081037111912311638237547
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 RevenueFromContractWithCustomerExcludingAssessedTax-1.84.6-165.3-1.6-35.57.29.79.310.26.37.29.311.08.37.6-10.05.26.20.4-64.8-1.5-13.8-44.6-11.00.44.14.92.62.10.3-13.4-1.81.92.43.25.88.07.75.78.89.29.53.72.37.25.2

Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax

us-gaap:OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax

us-gaap:OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax


Other
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-30
Value7.0-4.82314-23.49.8-16.3-8.511-10.2-13.8-26.2230.1244.410-27.5-4.4-9.8-5.4-18.3-16.219-21.8-21.4-16.67.7-3.311124.5-13.04.215-14.69.4-1.4-14.4
Percentage of OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax1.1-0.73.91.8-2.41.0-1.6-0.81.1-1.0-1.4-2.62.40.02.80.51.2-3.5-0.6-1.2-0.7-2.5-1.91.9-1.9-2.0-1.60.7-0.31.21.30.4-1.10.41.3-1.10.7-0.1-1.1

Other Comprehensive Income Loss Net Of Tax

us-gaap:OtherComprehensiveIncomeLossNetOfTax

us-gaap:OtherComprehensiveIncomeLossNetOfTax


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
Value3415-88.35043-15.7-138.6187.543-143.5-8.7-2.542-11.1554.424-137.1101918-90.9-22.2240.4-278.7122817270221313-151.6371216-303.23.8
Percentage of OtherComprehensiveIncomeLossNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax5.62.3-13.48.45.6-1.6-13.61.80.74.3-13.8-0.9-0.24.3-1.26.40.52.8-17.21.32.42.4-12.3-2.72.30.0-26.61.22.61.729.52.31.21.2-14.83.00.91.2-24.20.3

us-gaap:OtherComprehensiveIncomeLossNetOfTax us-gaap:StatementEquityComponents

us-gaap:AccumulatedOtherComprehensiveIncome


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-31
Value3215-95.04443-14.9-140.3231138-142.50.30.635-11.5504.222-132.0122119-89.1-18.1230.6-277.8103018269221113-153.5361315-304.3
Percentage of OtherComprehensiveIncomeLossNetOfTax94.496.2107.688.0101.294.9101.2125.0148.088.099.3-3.4-24.083.8103.691.195.591.896.3115.4107.6108.398.081.597.9150.099.785.5104.2110.599.799.685.796.4101.398.4109.996.4100.4
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax5.22.2-14.47.45.7-1.6-13.82.31.03.8-13.70.00.13.6-1.35.90.52.6-16.61.62.62.6-12.1-2.22.30.1-26.51.02.71.929.42.31.01.1-15.03.01.01.2-24.3
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:AccumulatedOtherComprehensiveIncome0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:NoncontrollingInterest


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-31
Value1.90.66.76.0-0.5-0.81.7-4.6-3.65.2-1.0-9.0-3.16.90.45.00.22.0-5.1-1.6-1.5-1.5-1.8-4.10.5-0.2-0.91.8-1.2-1.80.90.11.90.51.90.6-1.20.61.1
Percentage of OtherComprehensiveIncomeLossNetOfTax5.63.8-7.612.0-1.25.1-1.2-25.0-48.012.00.7103.4124.016.2-3.68.94.58.23.7-15.4-7.6-8.32.018.52.1-50.00.314.5-4.2-10.50.30.414.33.6-1.31.6-9.93.6-0.4
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.30.11.01.0-0.1-0.10.2-0.5-0.30.5-0.1-0.9-0.30.70.00.60.00.2-0.6-0.2-0.2-0.2-0.2-0.50.0-0.0-0.10.2-0.1-0.20.10.00.20.00.20.0-0.10.00.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:NoncontrollingInterest0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Other Nonoperating Income Expense

us-gaap:OtherNonoperatingIncomeExpense

us-gaap:OtherNonoperatingIncomeExpense


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value1.41.5-0.4-0.40.5-0.9-13.26718-2.9-1.90.83.8170.30.20.23.30.60.01.00.8-0.70.80.60.91.21.01.30.60.40.4-0.11.1-0.50.20.10.40.5-0.30.30.10.42.00.20.4
Percentage of OtherNonoperatingIncomeExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.20.2-0.1-0.10.1-0.1-1.36.61.7-0.3-0.20.10.41.80.00.00.00.40.10.00.10.1-0.10.10.10.10.10.10.10.10.00.0-0.00.1-0.00.00.00.00.0-0.00.00.00.00.20.00.0

Profit Loss

us-gaap:ProfitLoss

us-gaap:ProfitLoss


Profit
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-44.4-2.4-1116.3-47.0-419.923601157816455575605.2-119.4132113-527.2-15.5-98.1-223.3-141.3-13.912252.9-0.7-17.9175-32.26.6111337585834646658173.33819
Percentage of ProfitLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-7.2-0.3-169.6-7.9-54.52.55.911.37.31.64.35.47.56.20.6-13.71.52.41.7-68.4-1.9-13.0-30.2-17.0-1.41.12.40.3-0.1-1.819.2-3.30.61.01.33.14.34.32.74.74.94.81.70.33.62.2

us-gaap:ProfitLoss us-gaap:StatementEquityComponents

us-gaap:NoncontrollingInterest


Profit
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value4.85.54.6999999999999993.12.72.53.54.33.41.33.95.12.82.53.51.83.33.63.83.63.33.13.63.32.52.63.32.12.21.62.21.63.02.02.32.12.51.92.02.42.32.31.81.6
Percentage of ProfitLoss-10.8-229.2-0.4-6.6-0.610.65.83.74.38.08.79.23.74.167.3-1.524.617.127.7-0.7-21.3-3.2-1.6-2.3-18.020.6-471.4-11.71.3-5.033.313.822.25.43.93.67.33.03.04.113.269.74.78.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.80.80.70.50.40.30.30.40.30.10.40.50.30.30.40.20.40.40.50.50.40.40.50.40.20.20.30.20.20.20.20.10.30.20.20.20.20.10.10.20.20.20.20.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:NoncontrollingInterest0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:RetainedEarnings


Profit
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-49.2-7.9-1121.0-50.1-422.621561117515415072581.7-121.210179.9-530.8-18.8-101.2-226.9-144.6-16.410.022-0.7-4.0-20.0173-33.84.410.01035565631626456151.03618
Percentage of ProfitLoss110.8329.2100.4106.6100.689.494.296.395.792.091.390.896.395.932.7101.575.482.972.3100.7121.3103.2101.6102.3118.079.487.4-24.1571.4111.798.7105.066.786.277.894.696.196.492.797.097.095.986.830.395.391.9
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-8.0-1.1-170.3-8.4-54.92.25.510.97.01.54.05.07.25.90.2-13.91.12.01.2-68.9-2.3-13.4-30.7-17.4-1.60.92.1-0.1-0.4-2.018.9-3.50.40.81.02.94.24.22.54.64.74.61.50.13.52.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:RetainedEarnings0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Revenue From Contract With Customer Excluding Assessed Tax

us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax

us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
Value6166926585987709551018101810801004103710201009979909869880865796770810757738832102211251047106911199879159721135117910211220135713521251135213511227103710581052899815697710831
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ConsolidationItems

us-gaap:OperatingSegments


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
Value65874170062382210361066106911351051107510671051101894289891689681979683578976686710671169109511141161103395799610811127
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax106.8107.0106.4104.2106.8108.4104.7105.0105.1104.6103.6104.7104.1104.0103.6103.4104.1103.6102.9103.4103.1104.2103.7104.2104.4103.9104.5104.2103.8104.7104.6102.595.295.6
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax106.8107.0106.4104.2106.8108.4104.7105.0105.1104.6103.6104.7104.1104.0103.6103.4104.1103.6102.9103.4103.1104.2103.7104.2104.4103.9104.5104.2103.8104.7104.6102.595.295.6
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OperatingSegments100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ConsolidationItems, us-gaap:ContractWithCustomerSalesChannel, us-gaap:StatementBusinessSegments

us-gaap:OperatingSegments, ati:AerospaceandDefenseMarket, ati:AdvancedAlloysSolutions


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value62749174113133128125127125
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax10.210.713.912.414.714.012.612.311.812.4
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax10.210.713.912.414.714.012.612.311.812.4
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OperatingSegments ati:AerospaceandDefenseMarket ati:AdvancedAlloysSolutions100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OperatingSegments, ati:AerospaceandDefenseMarket, ati:HighPerformanceMaterialsComponents


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value218179164171252358463437512465459446438426399389398381
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax35.526.024.928.732.837.645.543.047.446.344.343.843.443.643.944.845.344.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax35.526.024.928.732.837.645.543.047.446.344.343.843.443.643.944.845.344.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OperatingSegments ati:AerospaceandDefenseMarket ati:HighPerformanceMaterialsComponents100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OperatingSegments, ati:AutomotiveMarket, ati:AdvancedAlloysSolutions


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value66897557497470717073
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax10.812.911.59.76.57.87.07.06.57.3
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax10.812.911.59.76.57.87.07.06.57.3
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OperatingSegments ati:AutomotiveMarket ati:AdvancedAlloysSolutions100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OperatingSegments, ati:AutomotiveMarket, ati:HighPerformanceMaterialsComponents


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value1.42.01.01.51.02.01.52.33.13.62.12.02.82.62.42.42.02.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.20.30.20.30.10.20.10.20.30.40.20.20.30.30.30.30.20.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.20.30.20.30.10.20.10.20.30.40.20.20.30.30.30.30.20.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OperatingSegments ati:AutomotiveMarket ati:HighPerformanceMaterialsComponents100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OperatingSegments, ati:ConstructionMiningMarket, ati:AdvancedAlloysSolutions


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value15373124293835383939
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax2.65.44.74.13.94.03.53.83.63.9
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax2.65.44.74.13.94.03.53.83.63.9
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OperatingSegments ati:ConstructionMiningMarket ati:AdvancedAlloysSolutions100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OperatingSegments, ati:ConstructionMiningMarket, ati:HighPerformanceMaterialsComponents


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value6.15.14.34.05.05.35.25.413181718191713131211
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax1.00.70.70.70.60.60.50.51.21.81.71.81.91.81.51.61.41.3
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax1.00.70.70.70.60.60.50.51.21.81.71.81.91.81.51.61.41.3
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OperatingSegments ati:ConstructionMiningMarket ati:HighPerformanceMaterialsComponents100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OperatingSegments, ati:ElectronicDevicesMarket, ati:AdvancedAlloysSolutions


Revenue
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-31
Value4355453932443734
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax7.08.07.65.13.44.43.53.4
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax7.08.07.65.13.44.43.53.4
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OperatingSegments ati:ElectronicDevicesMarket ati:AdvancedAlloysSolutions100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OperatingSegments, ati:ElectronicDevicesMarket, ati:HighPerformanceMaterialsComponents


Revenue
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value0.20.30.20.20.31.81.71.21.13.21.02.31.50.91.11.21.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.00.00.00.00.00.20.20.10.10.30.10.20.20.10.10.10.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.00.00.00.00.00.20.20.10.10.30.10.20.20.10.10.10.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OperatingSegments ati:ElectronicDevicesMarket ati:HighPerformanceMaterialsComponents100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OperatingSegments, ati:EnergyMarket, ati:AdvancedAlloysSolutions


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value69118115106144146141181180140
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax11.317.117.517.718.815.313.917.816.714.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax11.317.117.517.718.815.313.917.816.714.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OperatingSegments ati:EnergyMarket ati:AdvancedAlloysSolutions100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OperatingSegments, ati:EnergyMarket, ati:HighPerformanceMaterialsComponents


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value48303424222455363428323040
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax7.94.45.34.13.02.55.53.63.22.83.13.04.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax7.94.45.34.13.02.55.53.63.22.83.13.04.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OperatingSegments ati:EnergyMarket ati:HighPerformanceMaterialsComponents100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OperatingSegments, ati:FoodEquipmentandAppliancesMarket, ati:AdvancedAlloysSolutions


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value20352733475049534953
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax3.35.14.25.76.15.34.85.34.65.3
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax3.35.14.25.76.15.34.85.34.65.3
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OperatingSegments ati:FoodEquipmentandAppliancesMarket ati:AdvancedAlloysSolutions100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OperatingSegments, ati:FoodEquipmentandAppliancesMarket, ati:HighPerformanceMaterialsComponents


Revenue
Period End2021-06-302020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value0.10.00.10.00.00.20.00.10.10.20.00.10.10.20.50.3
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.10.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.10.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OperatingSegments ati:FoodEquipmentandAppliancesMarket ati:HighPerformanceMaterialsComponents100.00.0100.00.00.0100.00.0100.0100.0100.00.0100.0100.0100.0100.0100.0

us-gaap:OperatingSegments, ati:MedicalMarket, ati:AdvancedAlloysSolutions


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value17171316192122222121
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax2.82.62.12.82.52.32.22.22.02.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax2.82.62.12.82.52.32.22.22.02.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OperatingSegments ati:MedicalMarket ati:AdvancedAlloysSolutions100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OperatingSegments, ati:MedicalMarket, ati:HighPerformanceMaterialsComponents


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value14119.8101017403738423744464136414547
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax2.41.61.51.81.31.83.93.73.64.23.64.34.64.24.04.85.25.4
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax2.41.61.51.81.31.83.93.73.64.23.64.34.64.24.04.85.25.4
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OperatingSegments ati:MedicalMarket ati:HighPerformanceMaterialsComponents100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OperatingSegments, ati:OtherMarket, ati:AdvancedAlloysSolutions


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value19232118263727302121
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax3.23.43.33.03.43.92.73.02.02.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax3.23.43.33.03.43.92.73.02.02.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OperatingSegments ati:OtherMarket ati:AdvancedAlloysSolutions100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OperatingSegments, ati:OtherMarket, ati:HighPerformanceMaterialsComponents


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value11128.28.89.012161621262324242522192320
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax1.81.71.21.51.21.31.61.62.02.62.32.42.52.62.42.32.62.4
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax1.81.71.21.51.21.31.61.62.02.62.32.42.52.62.42.32.62.4
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OperatingSegments ati:OtherMarket ati:HighPerformanceMaterialsComponents100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ConsolidationItems, us-gaap:MajorCustomers

us-gaap:OperatingSegments, ati:ExternalCustomers


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-31
Value616692658598770955101810181080100410371020100997990986988086579677081075773883210221125
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OperatingSegments ati:ExternalCustomers100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OperatingSegments, ati:InternalCustomers


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-31
Value4148422552804850554637474139322936302325243127354444
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax6.87.06.44.26.88.44.75.05.14.63.64.74.14.03.63.44.13.62.93.43.14.23.74.24.43.9
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax6.87.06.44.26.88.44.75.05.14.63.64.74.14.03.63.44.13.62.93.43.14.23.74.24.43.9
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OperatingSegments ati:InternalCustomers100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ConsolidationItems, us-gaap:MajorCustomers, us-gaap:StatementBusinessSegments

us-gaap:OperatingSegments, ati:ExternalCustomers, ati:AdvancedAlloysSolutions


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value315451436376469535521566547508
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax51.265.266.263.061.056.051.255.650.750.6
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax51.265.266.263.061.056.051.255.650.750.6
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OperatingSegments ati:ExternalCustomers ati:AdvancedAlloysSolutions100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OperatingSegments, ati:ExternalCustomers, ati:HighPerformanceMaterialsComponents


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-31
Value300240222221300420602551642601596585591560517512526510477461498493457474511542
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax48.834.833.837.039.044.059.254.259.559.857.457.458.657.356.959.059.858.959.959.961.565.161.957.050.048.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax48.834.833.837.039.044.059.254.259.559.857.457.458.657.356.959.059.858.959.959.961.565.161.957.050.048.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OperatingSegments ati:ExternalCustomers ati:HighPerformanceMaterialsComponents100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OperatingSegments, ati:InternalCustomers, ati:AdvancedAlloysSolutions


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value23242416365259596564
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax3.93.53.72.84.85.55.85.86.16.4
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax3.93.53.72.84.85.55.85.86.16.4
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OperatingSegments ati:InternalCustomers ati:AdvancedAlloysSolutions100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OperatingSegments, ati:InternalCustomers, ati:HighPerformanceMaterialsComponents


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-31
Value1824178.816282425312211291918161316138.612121416152222
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax2.93.52.71.52.13.02.42.52.92.31.12.92.01.91.81.51.91.51.11.71.62.02.31.82.22.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax2.93.52.71.52.13.02.42.52.92.31.12.92.01.91.81.51.91.51.11.71.62.02.31.82.22.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OperatingSegments ati:InternalCustomers ati:HighPerformanceMaterialsComponents100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:OperatingSegments, ati:AdvancedAlloysSolutions


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value339476460393506587581626612572
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax55.168.769.965.865.761.557.061.556.756.9
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax55.168.769.965.865.761.557.061.556.756.9
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OperatingSegments ati:AdvancedAlloysSolutions100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OperatingSegments, ati:HighPerformanceMaterialsComponents


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
Value318265240230316448626577673623607615611560533526543510485474511507474490533564522527531504455481520560
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax51.738.336.538.541.146.961.556.762.462.158.560.360.657.358.760.661.758.961.061.663.167.064.258.952.250.249.849.347.551.149.749.545.847.5
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax51.738.336.538.541.146.961.556.762.462.158.560.360.657.358.760.661.758.961.061.663.167.064.258.952.250.249.849.347.551.149.749.545.847.5
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OperatingSegments ati:HighPerformanceMaterialsComponents100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

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

us-gaap:OperatingSegments, ati:SouthAmericaMiddleEastandOther, ati:AdvancedAlloysSolutions


Revenue
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-31
Value111411241417138.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax1.82.12.03.11.51.71.30.8
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax1.82.12.03.11.51.71.30.8
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OperatingSegments ati:SouthAmericaMiddleEastandOther ati:AdvancedAlloysSolutions100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OperatingSegments, ati:SouthAmericaMiddleEastandOther, ati:HighPerformanceMaterialsComponents


Revenue
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-30
Value6.85.27.09.82219181518149.01418
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax1.10.81.21.32.41.91.71.51.81.50.91.62.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax1.10.81.21.32.41.91.71.51.81.50.91.62.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OperatingSegments ati:SouthAmericaMiddleEastandOther ati:HighPerformanceMaterialsComponents100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OperatingSegments, country:CA, ati:AdvancedAlloysSolutions


Revenue
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-31
Value109.18.51110131415
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax1.71.31.41.41.11.31.31.5
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax1.71.31.41.41.11.31.31.5
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OperatingSegments country:CA ati:AdvancedAlloysSolutions100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OperatingSegments, country:CA, ati:HighPerformanceMaterialsComponents


Revenue
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-30
Value9.38.24.45.1112124191618161520
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax1.51.20.70.71.22.12.31.91.61.81.71.82.3
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax1.51.20.70.71.22.12.31.91.61.81.71.82.3
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OperatingSegments country:CA ati:HighPerformanceMaterialsComponents100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OperatingSegments, country:US, ati:AdvancedAlloysSolutions


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value172271259219311378345364350352
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax27.939.239.336.740.439.633.935.832.435.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax27.939.239.336.740.439.633.935.832.435.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OperatingSegments country:US ati:AdvancedAlloysSolutions100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OperatingSegments, country:US, ati:HighPerformanceMaterialsComponents


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-30
Value157128118129166227314312357336315316292289276273271
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax25.618.518.021.621.623.830.830.633.133.430.431.028.929.630.331.530.9
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax25.618.518.021.621.623.830.830.633.133.430.431.028.929.630.331.530.9
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OperatingSegments country:US ati:HighPerformanceMaterialsComponents100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OperatingSegments, srt:Asia, ati:AdvancedAlloysSolutions


Revenue
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-31
Value94122103919412012280
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax15.417.717.211.89.911.811.38.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax15.417.717.211.89.911.811.38.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OperatingSegments srt:Asia ati:AdvancedAlloysSolutions100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OperatingSegments, srt:Asia, ati:HighPerformanceMaterialsComponents


Revenue
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-30
Value40201927254860526071484540
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax6.62.93.33.62.64.85.65.36.07.14.95.24.6
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax6.62.93.33.62.64.85.65.36.07.14.95.24.6
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OperatingSegments srt:Asia ati:HighPerformanceMaterialsComponents100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OperatingSegments, srt:Europe, ati:AdvancedAlloysSolutions


Revenue
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-31
Value2734343237514652
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax4.44.95.74.23.95.14.35.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax4.44.95.74.23.95.14.35.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OperatingSegments srt:Europe ati:AdvancedAlloysSolutions100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OperatingSegments, srt:Europe, ati:HighPerformanceMaterialsComponents


Revenue
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-30
Value86796092133150181178173195197164176
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax14.011.410.211.914.014.816.817.717.019.320.119.020.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax14.011.410.211.914.014.816.817.717.019.320.119.020.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OperatingSegments srt:Europe ati:HighPerformanceMaterialsComponents100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ContractWithCustomerSalesChannel

ati:AerospaceandDefenseMarket


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value281254255246365492529503572525521499481462437427435417
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax45.636.738.941.247.551.551.949.453.052.350.348.947.747.248.149.249.548.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax45.636.738.941.247.551.551.949.453.052.350.348.947.747.248.149.249.548.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax ati:AerospaceandDefenseMarket100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

ati:AutomotiveMarket


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value689176595076727373767885807967616875
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax11.013.211.69.96.68.07.17.26.87.77.68.38.08.17.47.17.88.8
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax11.013.211.69.96.68.07.17.26.87.77.68.38.08.17.47.17.88.8
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax ati:AutomotiveMarket100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

ati:ConstructionMiningMarket


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value214235283443404352575658555548484650
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax3.66.15.44.74.54.64.04.34.95.85.45.75.55.75.35.65.35.8
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax3.66.15.44.74.54.64.04.34.95.85.45.75.55.75.35.65.35.8
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax ati:ConstructionMiningMarket100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

ati:ElectronicDevicesMarket


Revenue
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value4355453933464438344741353243423134
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax7.08.07.75.13.54.64.43.53.44.54.03.53.44.84.93.64.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax7.08.07.75.13.54.64.43.53.44.54.03.53.44.84.93.64.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax ati:ElectronicDevicesMarket100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

ati:EnergyMarket


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value11814915013016717059369771686005968
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax19.221.522.821.821.717.958.36.97.216.857.85.96.8
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax19.221.522.821.821.717.958.36.97.216.857.85.96.8
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax ati:EnergyMarket100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

ati:FoodEquipmentandAppliancesMarket


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value203527334750495349536358635857545559
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax3.45.14.25.76.15.34.85.34.65.36.15.86.36.06.36.36.36.8
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax3.45.14.25.76.15.34.85.34.65.36.15.86.36.06.36.36.36.8
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax ati:FoodEquipmentandAppliancesMarket100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

ati:MedicalMarket


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value322923272938424142464047504440444850
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax5.24.23.54.63.94.04.24.03.94.63.94.75.04.64.45.15.55.8
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax5.24.23.54.63.94.04.24.03.94.63.94.75.04.64.45.15.55.8
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax ati:MedicalMarket100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

ati:OtherMarket


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value303530263550394138424341414039435234
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax5.05.14.64.54.55.23.94.13.64.24.14.14.14.14.35.05.94.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax5.05.14.64.54.55.23.94.13.64.24.14.14.14.14.35.05.94.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax ati:OtherMarket100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:StatementGeographical

ati:SouthAmericaMiddleEastandOther


Revenue
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-31
Value1719183337363123303021323127
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax2.92.83.14.43.93.62.92.33.03.02.23.83.63.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax2.92.83.14.43.93.62.92.33.03.02.23.83.63.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax ati:SouthAmericaMiddleEastandOther100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

country:CA


Revenue
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-31
Value2017121622252926232927212823
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax3.22.52.22.12.32.52.72.62.32.92.82.43.22.8
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax3.22.52.22.12.32.52.72.62.32.92.82.43.22.8
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax country:CA100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

country:US


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value329399377348477606587605640621610607575554514506524525
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax53.557.757.358.361.963.457.759.459.361.858.859.657.056.656.658.359.660.6
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax53.557.757.358.361.963.457.759.459.361.858.859.657.056.656.658.359.660.6
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax country:US100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

srt:Asia


Revenue
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-30
Value13514212211811916417112314414315012094
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax22.020.620.615.412.516.115.912.314.214.215.413.810.7
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax22.020.620.615.412.516.115.912.314.214.215.413.810.7
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax srt:Asia100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

srt:Europe


Revenue
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-30
Value11311394124171186207211213230225188201
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax18.416.315.916.117.918.319.221.020.922.823.021.722.9
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax18.416.315.916.117.918.319.221.020.922.823.021.722.9
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax srt:Europe100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Revenues

us-gaap:Revenues

us-gaap:Revenues


Revenues
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
Value6166926585987709551018101810801004103710201009979909869880865796770810757738832102211251047106911199879159721135117910211220135713521251135213511227103710581052899815697710831
Percentage of Revenues100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

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
Value605452454458666567687265626761666659656059624062726370686567667082859291901039796998888657674
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 RevenueFromContractWithCustomerExcludingAssessedTax9.87.88.07.65.86.16.56.46.36.87.06.46.26.96.87.67.66.98.27.97.38.35.57.57.15.66.76.45.96.97.27.37.27.39.07.56.77.67.87.17.37.28.66.27.28.2

Assets

us-gaap:Assets

us-gaap:Assets


Assets
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-312008-12-31
Value397440684034506351695807563456285549549155015389539353505185507551865154517051925861571957516161646965566582650365706917689865996119617462476078608060786046612760495192449343464170
Percentage of Assets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:Assets us-gaap:StatementBusinessSegments

ati:AdvancedAlloysSolutions


Assetsus-gaap:
Period End2020-12-312019-12-312018-12-31
Value154826212590
Percentage of Assets38.446.547.1
Percentage of Assets38.446.547.1
Percentage of Assets ati:AdvancedAlloysSolutions100.0100.0100.0

ati:HighPerformanceMaterialsComponents


Assetsus-gaap:
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-31
Value175326892765266227443355355534523720
Percentage of Assets43.547.750.351.353.158.354.050.059.6
Percentage of Assets43.547.750.351.353.158.354.050.059.6
Percentage of Assets ati:HighPerformanceMaterialsComponents100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:Assets us-gaap:StatementGeographical

ati:OtherCountries


Assetsus-gaap:
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-312009-12-31
Value2302482182391391391441411791899182
Percentage of Assets5.74.44.04.62.72.42.22.02.93.12.01.9
Percentage of Assets5.74.44.04.62.72.42.22.02.93.12.01.9
Percentage of Assets ati:OtherCountries100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

country:CN


Assetsus-gaap:
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-31
Value325288287276249260280258276
Percentage of Assets8.15.15.25.34.84.54.33.74.4
Percentage of Assets8.15.15.25.34.84.54.33.74.4
Percentage of Assets country:CN100.0100.0100.0100.0100.0100.0100.0100.0100.0

country:GB


Assetsus-gaap:
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-31
Value122141136122122154196208239
Percentage of Assets3.02.52.52.42.42.73.03.03.8
Percentage of Assets3.02.52.52.42.42.73.03.03.8
Percentage of Assets country:GB100.0100.0100.0100.0100.0100.0100.0100.0100.0

country:US


Assetsus-gaap:
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-31
Value335649564859454745915073587961455505
Percentage of Assets83.288.088.387.788.888.289.389.188.1
Percentage of Assets83.288.088.387.788.888.289.389.188.1
Percentage of Assets country:US100.0100.0100.0100.0100.0100.0100.0100.0100.0

Liabilities

us-gaap:Liabilities

us-gaap:Liabilities


Liabilities
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value33673459339332143327361434413349341034443510330533513386334036273671366537253629376136143555364337563836386135113580393839034035353235773660333334043464347532853269298923642256
Percentage of Liabilities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets84.785.084.163.564.462.261.159.561.562.763.861.362.163.364.471.570.871.172.169.964.263.261.859.158.158.558.754.054.556.956.661.157.757.958.654.856.057.057.553.654.057.652.651.9

Liabilities And Stockholders Equity

us-gaap:LiabilitiesAndStockholdersEquity

us-gaap:LiabilitiesAndStockholdersEquity


Liabilities
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value39744068403450635169580756345628554954915501538953935350518550755186515451705192586157195751616164696556658265036570691768986599611961746247607860806078604661276049519244934346
Percentage of LiabilitiesAndStockholdersEquity100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
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

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
Value47348252117331735208720902168202619341885198019251846173913471413139413551471199419952082240525842594259828712875286628942466249124872479264225752515247527482690211020402012
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 Assets11.911.912.934.233.636.037.138.536.535.234.336.735.734.533.526.627.327.026.228.334.034.936.239.039.939.639.544.243.841.442.037.440.740.339.743.542.441.440.944.944.540.645.446.3

Assets Current

us-gaap:AssetsCurrent

us-gaap:AssetsCurrent


Assets
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value19962093206620862201250823032422226121772246212221262051191518041800176217661762195218001867209823832465248224152513289529502693233124462510248425272574256926892691278721151997
Percentage of AssetsCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets50.251.551.241.242.643.240.943.040.839.740.839.439.438.436.935.534.734.234.233.933.331.532.534.136.837.637.737.138.341.942.840.838.139.640.240.941.642.442.543.944.553.747.146.0

Cash

us-gaap:Cash

us-gaap:Cash


Cash
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-312009-12-31
Value1581902641401641492671025222339256245
Percentage of Cash100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets3.93.44.82.73.22.64.114.93.65.65.75.6

Cash And Cash Equivalents At Carrying Value

us-gaap:CashAndCashEquivalentsAtCarryingValue

us-gaap:CashAndCashEquivalentsAtCarryingValue


Cash
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312008-12-312007-12-31
Value472541645572539639490511281217382153122109141124154159229188322156149197250238269264355837102653574138304281210250380431367816432443378563708469623
Percentage of CashAndCashEquivalentsAtCarryingValue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets11.913.316.011.310.411.08.79.15.14.06.92.82.32.12.72.53.03.14.43.65.52.72.63.23.93.64.14.15.412.114.98.11.22.24.94.63.54.16.37.06.115.79.60.00.00.016.311.30.0

us-gaap:CashAndCashEquivalentsAtCarryingValue us-gaap:ConsolidationItems

us-gaap:CorporateNonSegment


Cash
Period End2020-12-312019-12-312018-12-31
Value727624502
Percentage of CashAndCashEquivalentsAtCarryingValue112.6127.2131.4
Percentage of Assets18.011.19.1
Percentage of Assets us-gaap:CorporateNonSegment0.00.00.0

us-gaap:CashAndCashEquivalentsAtCarryingValue us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName

ati:NextGenAlloysLLC


Cash
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value1.72.52.73.24.24.99.96.16.99.0101011127.0
Percentage of CashAndCashEquivalentsAtCarryingValue0.40.50.40.60.80.82.01.22.54.12.66.89.310.94.9
Percentage of Assets0.00.10.10.10.10.10.20.10.10.20.20.20.20.20.1
Percentage of Assets ati:NextGenAlloysLLC0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

ati:ShanghaiStalPrecisionStainlessSteelCoLtd


Cash
Period End2020-12-312019-12-312018-12-312017-12-31
Value38223526
Percentage of CashAndCashEquivalentsAtCarryingValue5.94.79.218.5
Percentage of Assets0.90.40.60.5
Percentage of Assets ati:ShanghaiStalPrecisionStainlessSteelCoLtd0.00.00.00.0

us-gaap:CashAndCashEquivalentsAtCarryingValue us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName, us-gaap:StatementBusinessSegments

ati:ShanghaiStalPrecisionStainlessSteelCoLtd, ati:AdvancedAlloysSolutions


Cash
Period End2021-06-302021-03-312020-09-302020-06-302020-03-31
Value4734483418
Percentage of CashAndCashEquivalentsAtCarryingValue10.06.38.56.52.9
Percentage of Assets1.20.81.00.70.3
Percentage of Assets ati:ShanghaiStalPrecisionStainlessSteelCoLtd ati:AdvancedAlloysSolutions0.00.00.00.00.0

Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents


Cash
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312017-12-31
Value472541645572539639490511281217382141
Percentage of CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets11.913.316.011.310.411.08.79.15.14.06.92.7

Accounts Receivable Net Current

us-gaap:AccountsReceivableNetCurrent

us-gaap:AccountsReceivableNetCurrent


Accounts
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value362423345388483593554596581565527588621606545525538504452454492442400497593690603623650557528576655681613685744753709769808694545392
Percentage of AccountsReceivableNetCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets9.110.48.67.79.410.29.810.610.510.39.610.911.511.310.510.410.49.88.78.78.47.77.08.19.210.59.29.69.98.17.78.710.711.09.811.312.212.411.712.613.413.412.19.0

Inventory Net

us-gaap:InventoryNet

us-gaap:InventoryNet


Inventory
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value105910479971035110311811155116812171254121112391254121011761101107610511037107810941166127113561472147214721417140614081322134415041537153614601512151113841434146512311024825
Percentage of InventoryNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets26.625.824.720.521.320.320.520.821.922.822.023.023.322.622.721.720.820.420.120.818.720.422.122.022.822.522.421.821.420.419.220.424.624.924.624.024.924.922.923.424.223.722.819.0

Inventory Finished Goods

us-gaap:InventoryFinishedGoods

us-gaap:InventoryFinishedGoods


Inventory
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value14316418119118617116118018219219119017618116516415916016116916416418419019117717216515116116216419519620921422621919919119014312696
Percentage of InventoryFinishedGoods100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets3.64.04.53.83.63.02.93.23.33.53.53.53.33.43.23.23.13.13.13.32.82.93.23.13.02.72.62.52.32.32.32.53.23.23.33.53.73.63.33.13.22.82.82.2

Inventory L I F O Reserve

us-gaap:InventoryLIFOReserve

us-gaap:InventoryLIFOReserve


Inventory
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value-29.9-37.3-44.1-41.1-47.6-45.6-33.6-6.7-13.9-4.7-2.9-1.7-3.7-23.1-43.1-45.8-79.1-89.3-97.3-113.3-131.8-136.1-136.4-85.1-9.3-4.3-4.8188.5-20.4-29.412507676124146153153159172166163102
Percentage of InventoryLIFOReserve100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets-0.8-0.9-1.1-0.8-0.9-0.8-0.6-0.1-0.3-0.1-0.1-0.0-0.1-0.4-0.8-0.9-1.5-1.7-1.9-2.2-2.2-2.4-2.4-1.4-0.1-0.1-0.10.30.1-0.3-0.40.20.81.21.22.02.42.52.52.62.83.23.62.4

Inventory Raw Materials And Supplies

us-gaap:InventoryRawMaterialsAndSupplies

us-gaap:InventoryRawMaterialsAndSupplies


Inventory
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value206224207210202174164199194212191204187175162157141148149157194207216235239234249262293291277330359367351287274242205231239191169158
Percentage of InventoryRawMaterialsAndSupplies100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets5.25.55.14.23.93.02.93.53.53.93.53.83.53.33.13.12.72.92.93.03.33.63.83.83.73.63.84.04.54.24.05.05.96.05.64.74.54.03.43.84.03.73.83.6

Other Assets Current

us-gaap:OtherAssetsCurrent

us-gaap:OtherAssetsCurrent


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value5038384833516410814092748980865252304647404335454766641361099786671209789565760599554364211271
Percentage of OtherAssetsCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets1.30.90.91.00.70.91.11.92.51.71.41.71.51.61.01.00.60.90.90.80.70.60.80.81.01.02.11.71.51.31.01.81.61.40.91.01.01.01.60.90.60.82.51.6

Land

us-gaap:Land

us-gaap:Land


Land
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
Value3434343534343434343131313131313131313131303031303030303030303029343434343434343434262524
Percentage of Land100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.90.90.90.70.70.60.60.60.60.60.60.60.60.60.60.60.60.60.60.60.50.50.50.50.50.50.50.50.50.40.40.50.60.60.60.60.60.60.60.60.60.50.60.6

Machinery And Equipment Gross

us-gaap:MachineryAndEquipmentGross

us-gaap:MachineryAndEquipmentGross


Machinery
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
Value27912768273637213681365636713612359236533622364636283618359735623527352134973646392439063858379237623714370236683618357235263431347833773344326432223183314630843048276627502607
Percentage of MachineryAndEquipmentGross100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets70.368.067.873.571.263.065.264.264.766.565.867.767.367.669.470.268.068.367.670.267.068.367.161.658.256.756.256.455.151.651.152.056.854.753.553.753.052.452.050.350.453.361.260.0

Property Plant And Equipment Gross

us-gaap:PropertyPlantAndEquipmentGross

us-gaap:PropertyPlantAndEquipmentGross


Property
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value34013372333646404593455245384467444445384505452845094499447344374398438343584525502649984937487048444797478147344680462545754409448343464299416940874007393738373788345934143223
Percentage of PropertyPlantAndEquipmentGross100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets85.682.982.791.688.878.480.579.480.182.781.984.083.684.186.387.484.885.084.387.285.887.485.879.174.973.272.672.871.266.966.366.873.370.468.868.667.265.965.162.662.666.676.074.2

Construction In Progress Gross

us-gaap:ConstructionInProgressGross

us-gaap:ConstructionInProgressGross


Construction
Period End2021-06-302021-03-312020-12-312020-09-302019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-312009-12-31
Value24425223322317783908711971186601346184270
Percentage of ConstructionInProgressGross100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets6.26.25.84.43.11.51.71.72.11.12.79.65.74.16.2

Accumulated Depreciation Depletion And Amortization Property Plant And Equipment

us-gaap:AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment

us-gaap:AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment


Accumulated
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value19151894186721742138210620882060203920672030205620302008197819461906188818592011206720362009193218971854181917971763173617011664179117491739168716431609156815291495146014251315
Percentage of AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets48.246.646.342.941.436.337.136.636.837.736.938.237.737.538.138.336.836.636.038.735.335.634.931.429.328.327.627.626.825.124.725.229.328.327.827.827.026.525.925.024.728.131.730.3

Property Plant And Equipment Net

us-gaap:PropertyPlantAndEquipmentNet

us-gaap:PropertyPlantAndEquipmentNet


Property
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value14861478146924662455244524502407240424702475247224792490249524902492249524982514295829622928293829462943296129372916288928742744269225972559248224442398236823072292199919891907
Percentage of PropertyPlantAndEquipmentNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets37.436.336.448.747.542.143.542.843.345.045.045.946.046.648.149.148.148.448.348.450.551.850.947.745.544.945.045.244.441.841.741.644.042.141.040.840.239.539.237.737.938.544.343.9

Goodwill

us-gaap:Goodwill

us-gaap:Goodwill


Goodwill
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
Value241241240238236520525523524536534536531534531531643642641644646648651780781777780782785775727728737736740740737739737740690209206207
Percentage of Goodwill100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets6.15.96.04.74.69.09.39.39.59.89.710.09.810.010.210.512.412.512.412.411.011.311.312.712.111.911.912.011.911.210.611.012.011.911.812.212.112.212.212.111.44.04.64.8

us-gaap:Goodwill us-gaap:ReportingUnit

ati:ForgedProducts


Goodwillus-gaap:
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-06-03
Value173173173460-10.410
Percentage of Goodwill72.072.773.488.4-2.00.0
Percentage of Assets4.33.43.47.9-0.20.0
Percentage of Assets ati:ForgedProducts0.00.00.00.00.00.0

ati:SpecialtyMaterials


Goodwillus-gaap:
Period End2020-12-312020-09-302020-06-30
Value676563
Percentage of Goodwill28.027.326.6
Percentage of Assets1.71.31.2
Percentage of Assets ati:SpecialtyMaterials0.00.00.0

us-gaap:Goodwill us-gaap:StatementBusinessSegments

ati:HighPerformanceMaterialsComponents


Goodwillus-gaap:
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-31
Value240525534531641651653
Percentage of Goodwill100.0100.0100.0100.0100.0100.083.8
Percentage of Assets6.09.39.710.212.411.39.9
Percentage of Assets ati:HighPerformanceMaterialsComponents13.719.519.320.023.419.418.4

Other Assets Noncurrent

us-gaap:OtherAssetsNoncurrent

us-gaap:OtherAssetsNoncurrent


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value249254259272276332355275358305245257257257242248250253262271302307304344357369358368352353342348358363365371370366370389374197182169
Percentage of OtherAssetsNoncurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets6.36.36.45.45.35.76.34.96.55.64.54.84.84.84.74.94.84.95.15.25.25.45.35.65.55.65.45.75.45.15.05.35.95.95.96.16.16.06.16.46.23.84.13.9

Accounts Payable Current

us-gaap:AccountsPayableCurrent

us-gaap:AccountsPayableCurrent


Accounts
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value265324290240275424521415420455498416429424420350355346294285308340380367487559556482556518471401445479499409451505490491503505394308
Percentage of AccountsPayableCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets6.78.07.24.85.37.39.27.47.68.39.17.78.07.98.16.96.96.75.75.55.36.06.66.07.58.58.57.48.57.56.86.17.37.88.06.77.48.38.18.08.39.78.87.1

Accrued Liabilities Current

us-gaap:AccruedLiabilitiesCurrent

us-gaap:AccruedLiabilitiesCurrent


Accrued
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value210230233213216209237238257220260228225205282286278276309310290291301329314288323305298294310304293280330336327324320315341270249258
Percentage of AccruedLiabilitiesCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets5.35.75.84.24.23.64.24.24.64.04.74.24.23.85.45.65.45.46.06.05.05.15.25.44.94.44.94.74.54.34.54.64.84.55.35.55.45.35.35.25.65.25.66.0

Contract With Customer Liability Current

us-gaap:ContractWithCustomerLiabilityCurrent

us-gaap:ContractWithCustomerLiabilityCurrent


Contract
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
Value1031181119710911478976977716970660.0
Percentage of ContractWithCustomerLiabilityCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0
Percentage of Assets2.62.92.81.92.12.01.41.71.21.41.31.31.31.20.0

Debt Current

us-gaap:DebtCurrent

us-gaap:DebtCurrent


Debt
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
Value19151712123101112116.46.61616631036671721055.46.71563.94.0181717171742041941942017171627282714415413914133
Percentage of DebtCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.50.40.40.20.25.40.20.20.20.10.10.30.31.20.20.71.33.42.00.10.12.70.10.10.30.30.30.30.36.16.16.46.90.30.30.30.40.50.52.42.52.73.10.8

Liabilities Current

us-gaap:LiabilitiesCurrent

us-gaap:LiabilitiesCurrent


Liabilities
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value59968965356361410598497637597608367307417597126737017957086016058286867378889379598399031253121111681186813871775823875861978998915791624
Percentage of LiabilitiesCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets15.116.916.211.111.918.215.113.613.713.815.213.613.714.213.713.313.515.413.711.610.314.511.912.013.714.314.612.913.718.117.617.719.413.213.912.813.514.414.316.016.517.617.614.4

Other Liabilities Current

us-gaap:OtherLiabilitiesCurrent

us-gaap:OtherLiabilitiesCurrent


Other
Period End2020-12-312019-12-31
Value233237
Percentage of OtherLiabilitiesCurrent100.0100.0
Percentage of Assets5.84.2

Long Term Debt

us-gaap:LongTermDebt us-gaap:AdjustmentsForNewAccountingPronouncements, us-gaap:DebtInstrument, us-gaap:LongtermDebtType

us-gaap:LongTermDebt

ati:AccountingStandardsUpdate202006, ati:AlleghenyTechnologiesConvertibleSeniorNotes35Due2025, us-gaap:ConvertibleDebt


Long
Period End2021-01-01
Value45
Percentage of LongTermDebt100.0
Percentage of Assets0.0
Percentage of Assets ati:AccountingStandardsUpdate202006 ati:AlleghenyTechnologiesConvertibleSeniorNotes35Due2025 us-gaap:ConvertibleDebt0.0

Long Term Debt And Capital Lease Obligations

us-gaap:LongTermDebtAndCapitalLeaseObligations

us-gaap:LongTermDebtAndCapitalLeaseObligations


Long
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
Value1602159815501529151613901387154115371536153515351535153515301877187617721771187018701492149115011502150915091509152015261527154210531462146314621474148114821483149614229211037
Percentage of LongTermDebtAndCapitalLeaseObligations100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets40.339.338.430.229.323.924.627.427.728.027.928.528.528.729.537.036.234.434.336.031.926.125.924.423.223.022.923.223.122.122.123.417.223.723.424.124.224.424.524.224.727.420.523.9

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
Value326312318317317
Percentage of PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent100.0100.0100.0100.0100.0
Percentage of Assets8.15.55.86.16.1
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
Value673731730697827
Percentage of PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent206.2234.1229.3219.3260.6
Percentage of Assets16.713.013.313.416.0
Percentage of Assets us-gaap:PensionPlansDefinedBenefit0.00.00.00.00.0

Minority Interest

us-gaap:MinorityInterest

us-gaap:MinorityInterest


Minority
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
Value1331261201161071041031111121121051031161171059910095899010410310199116113110108102100100979510910710210098969289928877
Percentage of MinorityInterest100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets3.33.13.02.32.11.81.82.02.02.01.91.92.22.22.02.01.91.81.71.81.81.81.81.61.81.71.71.71.61.51.51.51.61.81.71.71.61.61.61.51.51.82.01.8

Other Liabilities Noncurrent

us-gaap:OtherLiabilitiesNoncurrent

us-gaap:OtherLiabilitiesNoncurrent


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value220207189212206163160124124123696666627380838283868910610811210316215614914614814894100101109116117117124120127100100119
Percentage of OtherLiabilitiesNoncurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets5.55.14.74.24.02.82.92.22.22.21.31.21.21.21.41.61.61.61.61.71.51.91.91.81.62.52.42.32.22.12.11.41.61.61.81.91.91.92.12.02.11.92.22.7

Lessee Operating Lease Liability Payments Due Year Two

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearTwo

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearTwo


Lessee
Period End2020-12-31
Value16
Percentage of LesseeOperatingLeaseLiabilityPaymentsDueYearTwo100.0
Percentage of Assets0.4

Lessee Operating Lease Liability Payments Due Year Three

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearThree

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearThree


Lessee
Period End2020-12-31
Value12
Percentage of LesseeOperatingLeaseLiabilityPaymentsDueYearThree100.0
Percentage of Assets0.3

Lessee Operating Lease Liability Payments Due Year Four

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFour

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFour


Lessee
Period End2020-12-31
Value9300000.0
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
Value7600000.0
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
Value18
Percentage of LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive100.0
Percentage of Assets0.4

Operating Lease Liability

us-gaap:OperatingLeaseLiability

us-gaap:OperatingLeaseLiability


Operating
Period End2020-12-312019-12-312019-09-302019-06-302019-03-312019-01-01
Value677766676755
Percentage of OperatingLeaseLiability100.0100.0100.0100.0100.0100.0
Percentage of Assets1.71.41.21.21.20.0

Lessee Operating Lease Liability Payments Due

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDue

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDue


Lessee
Period End2020-12-31
Value84
Percentage of LesseeOperatingLeaseLiabilityPaymentsDue100.0
Percentage of Assets2.1

Lessee Operating Lease Liability Undiscounted Excess Amount

us-gaap:LesseeOperatingLeaseLiabilityUndiscountedExcessAmount

us-gaap:LesseeOperatingLeaseLiabilityUndiscountedExcessAmount


Lessee
Period End2020-12-31
Value16
Percentage of LesseeOperatingLeaseLiabilityUndiscountedExcessAmount100.0
Percentage of Assets0.4

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
Value47348252117331735208720902168202619341885198019251846173913471413139413551471199419952082240525842594259828712875286628942466249124872479264225752515247527482690211020402012
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 Assets11.911.912.934.233.636.037.138.536.535.234.336.735.734.533.526.627.327.026.228.334.034.936.239.039.939.639.544.243.841.442.037.440.740.339.743.542.441.440.944.944.540.645.446.3

Stockholders Equity Including Portion Attributable To Noncontrolling Interest

us-gaap:StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest

us-gaap:StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312008-12-312007-12-31
Value6066096411849184221922193227921382046199120832041196318441447151414891444156220992098218425052700270827092979297829672994256425862596258727442675261325712841278022032129213221302098208920292279
Percentage of StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets15.315.015.936.535.637.838.940.538.537.336.238.737.936.735.628.529.228.927.930.135.836.738.040.741.741.341.245.845.342.943.438.942.342.141.445.244.043.042.546.446.042.447.40.00.00.048.148.70.0

us-gaap:StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest us-gaap:AdjustmentsForNewAccountingPronouncements

ati:AccountingStandardsUpdate202006


Stockholders
Period End2021-01-01
Value-45.4
Percentage of StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest0.0
Percentage of Assets0.0
Percentage of Assets ati:AccountingStandardsUpdate2020060.0

us-gaap:StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest us-gaap:AdjustmentsForNewAccountingPronouncements, us-gaap:DebtInstrument, us-gaap:LongtermDebtType

ati:AccountingStandardsUpdate202006, ati:AlleghenyTechnologiesConvertibleSeniorNotes35Due2025, us-gaap:ConvertibleDebt


Stockholders
Period End2021-01-01
Value-45.4
Percentage of StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest0.0
Percentage of Assets0.0
Percentage of Assets ati:AccountingStandardsUpdate202006 ati:AlleghenyTechnologiesConvertibleSeniorNotes35Due2025 us-gaap:ConvertibleDebt0.0

us-gaap:AccountingStandardsUpdate202006, ati:AlleghenyTechnologiesConvertibleSeniorNotes35Due2025, us-gaap:ConvertibleDebt


Stockholders
Period End2021-01-01
Value-45.4
Percentage of StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest0.0
Percentage of Assets0.0
Percentage of Assets us-gaap:AccountingStandardsUpdate202006 ati:AlleghenyTechnologiesConvertibleSeniorNotes35Due2025 us-gaap:ConvertibleDebt0.0

us-gaap:StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest us-gaap:AdjustmentsForNewAccountingPronouncements, us-gaap:StatementEquityComponents

ati:AccountingStandardsUpdate202006, us-gaap:AdditionalPaidInCapital


Stockholders
Period End2021-01-01
Value-49.8
Percentage of StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest0.0
Percentage of Assets0.0
Percentage of Assets ati:AccountingStandardsUpdate202006 us-gaap:AdditionalPaidInCapital0.0

ati:AccountingStandardsUpdate202006, us-gaap:RetainedEarnings


Stockholders
Period End2021-01-01
Value4.4
Percentage of StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest0.0
Percentage of Assets0.0
Percentage of Assets ati:AccountingStandardsUpdate202006 us-gaap:RetainedEarnings0.0

us-gaap:AccountingStandardsUpdate202006, us-gaap:AdditionalPaidInCapital


Stockholders
Period End2021-01-01
Value-49.8
Percentage of StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest0.0
Percentage of Assets0.0
Percentage of Assets us-gaap:AccountingStandardsUpdate202006 us-gaap:AdditionalPaidInCapital0.0

us-gaap:AccountingStandardsUpdate202006, us-gaap:RetainedEarnings


Stockholders
Period End2021-01-01
Value4.4
Percentage of StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest0.0
Percentage of Assets0.0
Percentage of Assets us-gaap:AccountingStandardsUpdate202006 us-gaap:RetainedEarnings0.0

us-gaap:StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest us-gaap:CumulativeEffectPeriodOfAdoption, us-gaap:StatementScenario, us-gaap:DebtInstrument, us-gaap:LongtermDebtType, us-gaap:StatementEquityComponents

srt:CumulativeEffectPeriodOfAdoptionAdjustment, srt:ScenarioForecast, ati:AlleghenyTechnologiesConvertibleSeniorNotes35Due2025, us-gaap:ConvertibleDebt, us-gaap:RetainedEarnings


Stockholders
Period End2021-01-01
Value-4.6
Percentage of StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest0.0
Percentage of Assets0.0
Percentage of Assets srt:CumulativeEffectPeriodOfAdoptionAdjustment srt:ScenarioForecast ati:AlleghenyTechnologiesConvertibleSeniorNotes35Due2025 us-gaap:ConvertibleDebt us-gaap:RetainedEarnings0.0

us-gaap:StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest us-gaap:StatementEquityComponents

us-gaap:AccumulatedOtherComprehensiveIncome


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312008-12-312007-12-31
Value-1176.3-1208.6-1223.6-1128.6-1172.8-1216.6-1201.7-1061.4-1084.4-1095.5-1133.8-991.3-991.6-992.2-1027.8-1016.3-1067.2-1071.4-1093.7-961.7-973.7-994.9-1014.5-925.4-907.3-930.8-931.4-653.6-664.2-694.3-713.2-982.6-1004.8-1016.2-1029.4-875.9-912.4-925.7-941.6-637.3-639.6-649.0-665.1-653.9-662.8-673.4-673.5-746.5-237.2
Percentage of StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest-194.1-198.4-190.8-61.0-63.7-55.5-54.8-46.6-50.7-53.5-56.9-47.6-48.6-50.5-55.7-70.2-70.5-71.9-75.7-61.5-46.4-47.4-46.4-36.9-33.6-34.4-34.4-21.9-22.3-23.4-23.8-38.3-38.8-39.1-39.8-31.9-34.1-35.4-36.6-22.4-23.0-29.5-31.2-30.7-31.1-32.1-32.2-36.8-10.4
Percentage of Assets-29.6-29.7-30.3-22.3-22.7-21.0-21.3-18.9-19.5-20.0-20.6-18.4-18.4-18.5-19.8-20.0-20.6-20.8-21.2-18.5-16.6-17.4-17.6-15.0-14.0-14.2-14.1-10.1-10.1-10.0-10.3-14.9-16.4-16.5-16.5-14.4-15.0-15.2-15.6-10.4-10.6-12.5-14.80.00.00.0-15.5-17.90.0
Percentage of Assets us-gaap:AccumulatedOtherComprehensiveIncome0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:AdditionalPaidInCapital


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312008-12-312007-12-31
Value15871580162516221617159216181612160415991615160816041599159611961191118711881183117811711161115811541154116411611156116011851181117511681181118311691161120711881176653658647640640653651693
Percentage of StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest261.9259.4253.487.787.872.673.870.775.078.281.177.278.681.586.582.778.779.782.375.756.155.853.246.342.842.643.039.038.839.139.646.145.445.045.743.143.744.446.941.842.329.730.930.330.130.531.332.130.4
Percentage of Assets39.938.840.332.031.327.428.728.628.929.129.429.829.729.930.823.623.023.023.022.820.120.520.218.817.917.617.717.917.616.817.217.919.218.918.919.519.219.120.019.419.412.614.70.00.00.015.015.60.0
Percentage of Assets us-gaap:AdditionalPaidInCapital0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:CommonStock


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312008-12-312007-12-31
Value12121212121212121212121212121211111111111111111111111111111111111111111111111111111010101010101010
Percentage of StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest2.12.12.00.70.70.60.60.60.60.60.60.60.60.60.70.80.70.70.80.70.50.50.50.40.40.40.40.40.40.40.40.40.40.40.40.40.40.40.40.40.40.50.50.50.50.50.50.50.4
Percentage of Assets0.30.30.30.30.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.00.00.00.20.20.0
Percentage of Assets us-gaap:CommonStock0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:NoncontrollingInterest


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312008-12-312007-12-31
Value13312612011610710410311111211210510311611710599100958990104103101991161131101081021001009795109107102100989692899288848179777157
Percentage of StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest22.020.718.86.35.84.84.74.95.25.55.34.95.76.05.76.96.76.46.25.85.04.94.74.04.34.24.13.63.53.43.43.83.74.24.23.73.73.83.73.33.24.24.24.03.83.83.73.52.5
Percentage of Assets3.33.13.02.32.11.81.82.02.02.01.91.92.22.22.02.01.91.81.71.81.81.81.81.61.81.71.71.71.61.51.51.51.61.81.71.71.61.61.61.51.51.82.00.00.00.01.81.70.0
Percentage of Assets us-gaap:NoncontrollingInterest0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:RetainedEarnings


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312008-12-312007-12-31
Value531031061227127717001679162215111437142213801330125711841182130312941277126718061835194521812346238223982396241624402490233523892404242724432429239423612349230722642224222822452227223022861830
Percentage of StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest8.916.916.666.469.377.676.671.270.770.271.466.365.264.164.281.786.186.988.481.186.187.589.187.186.988.088.580.481.182.383.291.192.492.693.889.090.891.691.882.783.0102.8104.5104.5105.4106.1106.7112.780.3
Percentage of Assets1.42.52.624.224.729.329.828.827.226.225.825.624.723.522.823.325.125.124.724.430.832.133.835.436.336.336.436.836.835.336.135.439.039.038.940.240.039.439.138.338.143.649.50.00.00.051.354.80.0
Percentage of Assets us-gaap:RetainedEarnings0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:TreasuryStock


Stockholders
Period End2021-06-302021-03-312020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312008-12-312007-12-31
Value-4.7-4.70.0-0.8-18.2-18.2-18.3-19.7-30.6-30.6-30.6-31.7-26.1-25.9-25.4-27.1-28.0-27.9-27.7-28.7-21.3-20.4-20.6-22.2-44.3-44.5-44.2-51.3-79.6-78.8-79.2-81.1-111.3-119.8-122.6-126.6-162.7-162.9-164.2-168.7-188.0-183.7-184.0-185.2-208.6-244.8-75.4
Percentage of StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest-0.8-0.80.0-0.0-0.8-0.8-0.9-1.0-1.5-1.5-1.5-1.6-1.4-1.8-1.7-1.8-1.9-1.8-1.3-1.4-1.0-0.8-0.8-0.8-1.6-1.5-1.5-1.7-2.7-3.1-3.1-3.1-4.3-4.4-4.6-4.8-6.3-5.7-5.9-7.7-8.8-8.6-8.6-8.8-10.0-12.1-3.3
Percentage of Assets-0.1-0.10.0-0.0-0.3-0.3-0.3-0.4-0.6-0.6-0.6-0.6-0.5-0.5-0.5-0.5-0.5-0.5-0.5-0.5-0.4-0.3-0.3-0.3-0.7-0.7-0.7-0.7-1.2-1.2-1.3-1.3-1.8-2.0-2.0-2.1-2.7-2.7-2.7-3.2-4.20.00.00.0-4.8-5.90.0
Percentage of Assets us-gaap:TreasuryStock0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Common Stock Value

us-gaap:CommonStockValue

us-gaap:CommonStockValue


Common
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value1212121212121212121212121212121111111111111111111111111111111111111111111111111111101010
Percentage of CommonStockValue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.30.30.30.30.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.2

Additional Paid In Capital Common Stock

us-gaap:AdditionalPaidInCapitalCommonStock

us-gaap:AdditionalPaidInCapitalCommonStock


Additional
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value15871580162516221617159216181612160415991615160816041599159611961191118711881183117811711161115811541154116411611156116011851181117511681181118311691161120711881176653658653
Percentage of AdditionalPaidInCapitalCommonStock100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets39.938.840.332.031.327.428.728.628.929.129.429.829.729.930.823.623.023.023.022.820.120.520.218.817.917.617.717.917.616.817.217.919.218.918.919.519.219.120.019.419.412.614.715.0

Retained Earnings Accumulated Deficit

us-gaap:RetainedEarningsAccumulatedDeficit

us-gaap:RetainedEarningsAccumulatedDeficit


Retained
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value5310310612271277170016791622151114371422138013301257118411821303129412771267180618351945218123462382239823962416244024902335238924042427244324292394236123492307226422242230
Percentage of RetainedEarningsAccumulatedDeficit100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets1.42.52.624.224.729.329.828.827.226.225.825.624.723.522.823.325.125.124.724.430.832.133.835.436.336.336.436.836.835.336.135.439.039.038.940.240.039.439.138.338.143.649.551.3

Accumulated Other Comprehensive Income Loss Net Of Tax

us-gaap:AccumulatedOtherComprehensiveIncomeLossNetOfTax

us-gaap:AccumulatedOtherComprehensiveIncomeLossNetOfTax


Accumulated
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value-1176.3-1208.6-1223.6-1128.6-1172.8-1216.6-1201.7-1061.4-1084.4-1095.5-1133.8-991.3-991.6-992.2-1027.8-1016.3-1067.2-1071.4-1093.7-961.7-973.7-994.9-1014.5-925.4-907.3-930.8-931.4-653.6-664.2-694.3-713.2-982.6-1004.8-1016.2-1029.4-875.9-912.4-925.7-941.6-637.3-639.6-649.0-665.1-673.5
Percentage of AccumulatedOtherComprehensiveIncomeLossNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets-29.6-29.7-30.3-22.3-22.7-21.0-21.3-18.9-19.5-20.0-20.6-18.4-18.4-18.5-19.8-20.0-20.6-20.8-21.2-18.5-16.6-17.4-17.6-15.0-14.0-14.2-14.1-10.1-10.1-10.0-10.3-14.9-16.4-16.5-16.5-14.4-15.0-15.2-15.6-10.4-10.6-12.5-14.8-15.5

us-gaap:AccumulatedOtherComprehensiveIncomeLossNetOfTax us-gaap:StatementEquityComponents

ati:AccumulatedDeferredTaxAssetValuationAllowance


Accumulated
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312014-12-312013-12-31
Value-38.7-45.4-50.3-26.4-32.8-41.5-41.5-29.3-38.0-41.6-49.3-17.5-18.7-24.4-28.8-29.3-45.6-40.4-45.60.00.00.00.00.00.0
Percentage of AccumulatedOtherComprehensiveIncomeLossNetOfTax3.33.84.12.32.83.43.52.83.53.84.31.81.92.52.82.94.33.84.2-0.0-0.0-0.0-0.0-0.0-0.0
Percentage of Assets-1.0-1.1-1.2-0.5-0.6-0.7-0.7-0.5-0.7-0.8-0.9-0.3-0.3-0.5-0.6-0.6-0.9-0.8-0.90.00.00.00.00.00.0
Percentage of Assets ati:AccumulatedDeferredTaxAssetValuationAllowance0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:AccumulatedDefinedBenefitPlansAdjustment


Accumulated
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-31
Value-1086.9-1103.4-1119.9-1036.2-1051.8-1067.4-1083.1-957.3-973.4-989.7-1005.8-912.2-926.2-940.2-954.5-933.0-943.5-954.7-965.5-902.3-913.7-925.1-951.2-894.0-906.5-919.0-931.5-678.6-692.0-705.5-718.9-975.2-993.5-1011.8-1030.0
Percentage of AccumulatedOtherComprehensiveIncomeLossNetOfTax92.491.391.591.889.787.790.190.289.890.388.792.093.494.892.991.888.489.188.393.893.893.093.896.699.998.7100.0103.8104.2101.6100.899.298.999.6100.1
Percentage of Assets-27.4-27.1-27.8-20.5-20.3-18.4-19.2-17.0-17.5-18.0-18.3-16.9-17.2-17.6-18.4-18.4-18.2-18.5-18.7-17.4-15.6-16.2-16.5-14.5-14.0-14.0-14.2-10.4-10.5-10.2-10.4-14.8-16.2-16.4-16.5
Percentage of Assets us-gaap:AccumulatedDefinedBenefitPlansAdjustment0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedges


Accumulated
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-31
Value5.11.12.11.3-3.7-8.5-0.59.90.03.9-4.83.1139.29.0-0.8-5.70.32.43.2-0.2-18.3-15.7-0.2182616205.0-2.6-9.6-12.2-3.75.7-2.7
Percentage of AccumulatedOtherComprehensiveIncomeLossNetOfTax-0.4-0.1-0.2-0.10.30.70.0-0.9-0.0-0.40.4-0.3-1.3-0.9-0.90.10.5-0.0-0.2-0.30.01.81.50.0-2.0-2.8-1.8-3.2-0.80.41.31.20.4-0.60.3
Percentage of Assets0.10.00.10.0-0.1-0.1-0.00.20.00.1-0.10.10.20.20.2-0.0-0.10.00.00.1-0.0-0.3-0.3-0.00.30.40.20.30.1-0.0-0.1-0.2-0.10.1-0.0
Percentage of Assets us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedges0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:AccumulatedTranslationAdjustment


Accumulated
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-31
Value-55.8-60.9-55.5-67.3-84.5-99.2-76.6-84.7-73.0-68.1-73.9-64.7-59.9-36.8-53.5-53.2-72.4-76.6-85.0-62.6-59.8-51.5-47.6-31.1-19.0-37.8-16.24.32213154.8-7.5-10.13.4
Percentage of AccumulatedOtherComprehensiveIncomeLossNetOfTax4.75.04.56.07.28.26.48.06.76.26.56.56.03.75.25.26.87.17.86.56.15.24.73.42.14.11.7-0.7-3.4-2.0-2.1-0.50.71.0-0.3
Percentage of Assets-1.4-1.5-1.4-1.3-1.6-1.7-1.4-1.5-1.3-1.2-1.3-1.2-1.1-0.7-1.0-1.0-1.4-1.5-1.6-1.2-1.0-0.9-0.8-0.5-0.3-0.6-0.20.10.30.20.20.1-0.1-0.20.1
Percentage of Assets us-gaap:AccumulatedTranslationAdjustment0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Treasury Stock Value

us-gaap:TreasuryStockValue

us-gaap:TreasuryStockValue


Treasury
Period End2021-06-302021-03-312020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value4.74.70.00.818181819303030312625252728272728212020224444445179787981111119122126162162164168188208
Percentage of TreasuryStockValue100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.10.10.00.00.30.30.30.40.60.60.60.60.50.50.50.50.50.50.50.50.40.30.30.30.70.70.70.71.21.21.31.31.82.02.02.12.72.72.73.24.24.8

Minority Interest

us-gaap:MinorityInterest

us-gaap:MinorityInterest


Minority
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
Value1331261201161071041031111121121051031161171059910095899010410310199116113110108102100100979510910710210098969289928877
Percentage of MinorityInterest100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets3.33.13.02.32.11.81.82.02.02.01.91.92.22.22.02.01.91.81.71.81.81.81.81.61.81.71.71.71.61.51.51.51.61.81.71.71.61.61.61.51.51.82.01.8

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-34.5-68.112159101-115.42409425-130.02768182-47.1763124-110.268-78.127-61.52217791294-0.719-56.9141169115-57.418118678-18.2189179-21.7-50.391129-121.4-72.0
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-5.6-9.818.59.913.1-12.123.69.32.4-12.926.68.08.1-4.88.43.62.8-12.78.5-10.13.4-8.13.02.17.81.19.0-0.11.7-5.815.417.410.2-4.917.815.25.7-1.315.113.3-1.6-4.18.812.2-11.5-8.0

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-33.7-25.1-39.499999999999986-27.4-36.6-25.2-67.713835-23.6-36.0-39.3-28.3-41.5-37.5-30.1-29.8-22.2-27.2-29.3-74.8-68.7-45.1-36.2-41.3-22.5-68.1-59.8-79.4-108.9383-171.5-137.0-86.2-134.6-79.3-95.8-69.0-109.7-70.7-402.6-41.7-84.4-35.8-46.0-50.6
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-5.5-3.6-6.0-4.6-4.8-2.6-6.613.53.2-2.3-3.5-3.9-2.8-4.2-4.1-3.5-3.4-2.6-3.4-3.8-9.2-9.1-6.1-4.3-4.0-2.0-6.5-5.6-7.1-11.041.9-17.6-12.1-7.3-13.2-6.5-7.1-5.1-8.8-5.2-29.8-3.4-8.1-3.4-4.4-5.6

Net Cash Provided By Used In Financing Activities

us-gaap:NetCashProvidedByUsedInFinancingActivities

us-gaap:NetCashProvidedByUsedInFinancingActivities


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value-1.0-11.0-8.71.1-164.3288-192.9-2.33.6-11.4-11.7-11.2-41.356-22.0-31.3-0.1620.4-26.5212137-25.1-34.6-25.3-21.0-20.7-30.4-422.6-23.3-33.6463-42.3-23.0-23.5-36.0-22.2-43.1-130.5-45.1-24.2476-17.6-29.1-17.4-22.7
Percentage of NetCashProvidedByUsedInFinancingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-0.2-1.6-1.30.2-21.330.2-18.9-0.20.3-1.1-1.1-1.1-4.15.8-2.4-3.6-0.07.20.1-3.426.218.1-3.4-4.2-2.5-1.9-2.0-2.8-37.8-2.4-3.747.7-3.7-2.0-2.3-2.9-1.6-3.2-10.4-3.3-1.838.8-1.7-2.7-1.7-2.5

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

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect


Cash
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value-69.2-104.27333-99.9148-20.50000000000001423064-165.0
Percentage of CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-11.2-15.011.25.5-13.015.5-2.022.65.9-16.4

Amortization Of Financing Costs

us-gaap:AmortizationOfFinancingCosts us-gaap:DebtInstrument, us-gaap:LongtermDebtType

us-gaap:AmortizationOfFinancingCosts

ati:AlleghenyTechnologiesConvertibleSeniorNotes35Due2025, us-gaap:ConvertibleDebt


Amortization
Period End2021-06-30
Value400000.0
Percentage of AmortizationOfFinancingCosts100.0

ati:AlleghenyTechnologiesConvertibleSeniorNotes4.75Due2022, us-gaap:ConvertibleDebt


Amortization
Period End2021-06-302020-06-30
Value100000.0400000.0
Percentage of AmortizationOfFinancingCosts25.00.0

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
Value36363535353736373838393838394040404040424344484748454544434446464848484848484746433735363534
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

us-gaap:DepreciationDepletionAndAmortization us-gaap:ConsolidationItems

us-gaap:OperatingSegments


Depreciation
Period End2021-06-302021-03-312020-06-302020-03-31
Value36363537
Percentage of DepreciationDepletionAndAmortization100.0100.0100.0100.0

us-gaap:DepreciationDepletionAndAmortization us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:OperatingSegments, ati:AdvancedAlloysSolutions


Depreciation
Period End2021-06-302021-03-312020-06-302020-03-31
Value16151517
Percentage of DepreciationDepletionAndAmortization44.442.943.045.6

us-gaap:OperatingSegments, ati:HighPerformanceMaterialsComponents


Depreciation
Period End2021-06-302021-03-312020-06-302020-03-31
Value19191919
Percentage of DepreciationDepletionAndAmortization52.954.354.852.3

us-gaap:OperatingSegments, us-gaap:Corporate


Depreciation
Period End2021-06-302021-03-312020-06-302020-03-31
Value1.01.00.80.8
Percentage of DepreciationDepletionAndAmortization2.82.82.22.1

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
Value-61.778-42.2-95.7-109.739-40.4144037-59.0-33.8156119-12.73452-1.9-38.55042-97.2-95.9-97.587-19.6-29.89128-52.3-31.0-26.068-72.4-58.5-8.944-60.1-38.829148-77.6539680
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
Value1150-38.9-67.5-77.625-13.2-48.8-6.743-28.7-14.64310875242414-42.0-15.4-72.0-105.3-84.5-116.80.4-0.35510-4.682-19.9-95.1-32.50.976-52.41.2127-50.3-30.210020712-40.981145
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
Value19-11.2-70.0-4.6-42.6-2.4-13.3-25.6-6.344-43.337-21.343-11.9-4.8-17.62413-17.43.20.4174.3-32.8303.19.8-26.39.3-62.2-43.0-20.948-18.5-18.0-22.5-5.11917-26.2-51.633-31.58.120
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-34.5-68.112159101-115.42409425-130.02768182-47.1763124-110.268-78.127-61.52217791294-0.719-56.9141169115-57.418118678-18.2189179-21.7-50.391129-121.4-72.0
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-5.6-9.818.59.913.1-12.123.69.32.4-12.926.68.08.1-4.88.43.62.8-12.78.5-10.13.4-8.13.02.17.81.19.0-0.11.7-5.815.417.410.2-4.917.815.25.7-1.315.113.3-1.6-4.18.812.2-11.5-8.0

Net Income Loss

us-gaap:NetIncomeLoss

us-gaap:NetIncomeLoss


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
Value-49.2-7.9-1121.0-50.1-422.621561117515415072581.7-121.210179.9-530.8-18.8-101.2-226.9-144.6-16.410.022-0.7-4.0-20.0173-33.84.410.01035565631626456151.03618371.4-13.45.9
Percentage of NetIncomeLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-8.0-1.1-170.3-8.4-54.92.25.510.97.01.54.05.07.25.90.2-13.91.12.01.2-68.9-2.3-13.4-30.7-17.4-1.60.92.1-0.1-0.4-2.018.9-3.50.40.81.02.94.24.22.54.64.74.61.50.13.52.04.60.2-1.90.7

Profit Loss

us-gaap:ProfitLoss

us-gaap:ProfitLoss


Profit
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-44.4-2.4-1116.3-47.0-419.923601157816455575605.2-119.4132113-527.2-15.5-98.1-223.3-141.3-13.912252.9-0.7-17.9175-32.26.6111337585834646658173.33819
Percentage of ProfitLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-7.2-0.3-169.6-7.9-54.52.55.911.37.31.64.35.47.56.20.6-13.71.52.41.7-68.4-1.9-13.0-30.2-17.0-1.41.12.40.3-0.1-1.819.2-3.30.61.01.33.14.34.32.74.74.94.81.70.33.62.2

us-gaap:ProfitLoss us-gaap:StatementEquityComponents

us-gaap:NoncontrollingInterest


Profit
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value4.85.54.6999999999999993.12.72.53.54.33.41.33.95.12.82.53.51.83.33.63.83.63.33.13.63.32.52.63.32.12.21.62.21.63.02.02.32.12.51.92.02.42.32.31.81.6
Percentage of ProfitLoss-10.8-229.2-0.4-6.6-0.610.65.83.74.38.08.79.23.74.167.3-1.524.617.127.7-0.7-21.3-3.2-1.6-2.3-18.020.6-471.4-11.71.3-5.033.313.822.25.43.93.67.33.03.04.113.269.74.78.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.80.80.70.50.40.30.30.40.30.10.40.50.30.30.40.20.40.40.50.50.40.40.50.40.20.20.30.20.20.20.20.10.30.20.20.20.20.10.10.20.20.20.20.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:NoncontrollingInterest0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:RetainedEarnings


Profit
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-49.2-7.9-1121.0-50.1-422.621561117515415072581.7-121.210179.9-530.8-18.8-101.2-226.9-144.6-16.410.022-0.7-4.0-20.0173-33.84.410.01035565631626456151.03618
Percentage of ProfitLoss110.8329.2100.4106.6100.689.494.296.395.792.091.390.896.395.932.7101.575.482.972.3100.7121.3103.2101.6102.3118.079.487.4-24.1571.4111.798.7105.066.786.277.894.696.196.492.797.097.095.986.830.395.391.9
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-8.0-1.1-170.3-8.4-54.92.25.510.97.01.54.05.07.25.90.2-13.91.12.01.2-68.9-2.3-13.4-30.7-17.4-1.60.92.1-0.1-0.4-2.018.9-3.50.40.81.02.94.24.22.54.64.74.61.50.13.52.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:RetainedEarnings0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

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-33.7-25.1-39.499999999999986-27.4-36.6-25.2-67.713835-23.6-36.0-39.3-28.3-41.5-37.5-30.1-29.8-22.2-27.2-29.3-74.8-68.7-45.1-36.2-41.3-22.5-68.1-59.8-79.4-108.9383-171.5-137.0-86.2-134.6-79.3-95.8-69.0-109.7-70.7-402.6-41.7-84.4-35.8-46.0-50.6
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-5.5-3.6-6.0-4.6-4.8-2.6-6.613.53.2-2.3-3.5-3.9-2.8-4.2-4.1-3.5-3.4-2.6-3.4-3.8-9.2-9.1-6.1-4.3-4.0-2.0-6.5-5.6-7.1-11.041.9-17.6-12.1-7.3-13.2-6.5-7.1-5.1-8.8-5.2-29.8-3.4-8.1-3.4-4.4-5.6

Payments To Acquire Productive Assets

us-gaap:PaymentsToAcquireProductiveAssets

us-gaap:PaymentsToAcquireProductiveAssets


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
Value3526412836297046272337302941373030242729756945364022685958392171711368613679956910971554285354651
Percentage of PaymentsToAcquireProductiveAssets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Net Cash Provided By Used In Financing Activities

us-gaap:NetCashProvidedByUsedInFinancingActivities

us-gaap:NetCashProvidedByUsedInFinancingActivities


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value-1.0-11.0-8.71.1-164.3288-192.9-2.33.6-11.4-11.7-11.2-41.356-22.0-31.3-0.1620.4-26.5212137-25.1-34.6-25.3-21.0-20.7-30.4-422.6-23.3-33.6463-42.3-23.0-23.5-36.0-22.2-43.1-130.5-45.1-24.2476-17.6-29.1-17.4-22.7
Percentage of NetCashProvidedByUsedInFinancingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-0.2-1.6-1.30.2-21.330.2-18.9-0.20.3-1.1-1.1-1.1-4.15.8-2.4-3.6-0.07.20.1-3.426.218.1-3.4-4.2-2.5-1.9-2.0-2.8-37.8-2.4-3.747.7-3.7-2.0-2.3-2.9-1.6-3.2-10.4-3.3-1.838.8-1.7-2.7-1.7-2.5

Proceeds From Issuance Of Long Term Debt

us-gaap:ProceedsFromIssuanceOfLongTermDebt

us-gaap:ProceedsFromIssuanceOfLongTermDebt


Proceeds
Period End2020-12-312020-09-302016-12-312016-09-302014-12-312013-12-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value0.06.40.00.00.00.00.00.00.00.00.00.00.05000.00.00.00.0
Percentage of ProceedsFromIssuanceOfLongTermDebt0.0100.00.00.00.00.00.00.00.00.00.00.00.0100.00.00.00.00.0

Debt Instrument Interest Rate Stated Percentage

us-gaap:DebtInstrumentInterestRateStatedPercentage us-gaap:DebtInstrument

us-gaap:DebtInstrumentInterestRateStatedPercentage

ati:AlleghenyTechnologiesConvertibleSeniorNotes4.75Due2022


Debt
Period End2020-12-312020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-30
Value4.750.04750.04750.04750.04750.04750.04750.04750.04750.04750.04750.04750.04750.04750.04750.04750.0475
Percentage of DebtInstrumentInterestRateStatedPercentage100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of LongTermDebtAndCapitalLeaseObligations0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0
Percentage of LongTermDebtAndCapitalLeaseObligations ati:AlleghenyTechnologiesConvertibleSeniorNotes4.75Due20220.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

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

ati:AlleghenyTechnologiesConvertibleSeniorNotes35Due2025, us-gaap:ConvertibleDebt


Debt
Period End2021-06-302021-03-312020-12-312020-09-302020-06-30
Value3.53.53.53.50.035
Percentage of DebtInstrumentInterestRateStatedPercentage0.00.073.70.00.0
Percentage of LongTermDebtAndCapitalLeaseObligations0.00.00.00.00.0
Percentage of LongTermDebtAndCapitalLeaseObligations ati:AlleghenyTechnologiesConvertibleSeniorNotes35Due2025 us-gaap:ConvertibleDebt0.00.00.00.00.0

Effective Income Tax Rate Continuing Operations

us-gaap:EffectiveIncomeTaxRateContinuingOperations

us-gaap:EffectiveIncomeTaxRateContinuingOperations


Effective
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-03-312016-09-302016-06-302016-03-312015-06-302015-03-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-09-302012-06-302011-09-302011-06-302010-09-302010-06-30
Value-1.7-0.2830.3140.0310.0690.0470.110.0610.0760.0870.0080.6260.2590.3560.3880.1220.8530.3850.2410.1430.2360.3110.3460.3270.3420.0250.37
Percentage of EffectiveIncomeTaxRateContinuingOperations100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Deferred Tax Liabilities

us-gaap:DeferredTaxLiabilities

us-gaap:DeferredTaxLiabilities


Deferred
Period End2020-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-312009-12-31
Value124.22.13.675820668563567393307
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 End2020-12-312019-12-312018-12-312018-09-302018-06-302017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-312009-12-31
Value208537478468468468681722677457611534318346
Percentage of DeferredTaxAssetsNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DeferredTaxAssetsNet us-gaap:ConsolidationItems

us-gaap:CorporateNonSegment


Deferred
Period End2020-12-312019-12-312018-12-31
Value5.1648.7
Percentage of DeferredTaxAssetsNet2.412.01.8

Unrecognized Tax Benefits

us-gaap:UnrecognizedTaxBenefits

us-gaap:UnrecognizedTaxBenefits


Unrecognized
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-312009-12-312008-12-312007-12-31
Value1514141417157372292917373438
Percentage of UnrecognizedTaxBenefits100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Deferred Tax Assets Valuation Allowance

us-gaap:DeferredTaxAssetsValuationAllowance

us-gaap:DeferredTaxAssetsValuationAllowance


Deferred
Period End2020-12-312019-12-312018-12-312018-09-302018-06-302017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-312009-12-31
Value46194194264264274322105343324222119
Percentage of DeferredTaxAssetsValuationAllowance100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

ati:AdjustedEarningsBeforeIncomeTaxesDepreciationAmortizationEBITDA

ati:AdjustedEarningsBeforeIncomeTaxesDepreciationAmortizationEBITDA


Adjusted
Period End2021-06-302021-03-312020-06-302020-03-31
Value53625799
Percentage of AdjustedEarningsBeforeIncomeTaxesDepreciationAmortizationEBITDA100.0100.0100.0100.0

ati:AdjustmentsToAdditionalPaidInCapitalConvertibleNoteCappedCall

ati:AdjustmentsToAdditionalPaidInCapitalConvertibleNoteCappedCall


Adjustments
Period End2020-12-312020-09-302020-06-30
Value0.00.419
Percentage of AdjustmentsToAdditionalPaidInCapitalConvertibleNoteCappedCall0.0100.0100.0

ati:AdjustmentsToAdditionalPaidInCapitalConvertibleNoteCappedCall us-gaap:StatementEquityComponents

us-gaap:AdditionalPaidInCapital


Adjustments
Period End2020-12-312020-09-302020-06-30
Value0.00.419
Percentage of AdjustmentsToAdditionalPaidInCapitalConvertibleNoteCappedCall0.0100.0100.0

ati:ContractwithCustomerAssetCurrentPeriodIncrease

ati:ContractwithCustomerAssetCurrentPeriodIncrease


Contractwith
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
Value2325281812251711212326241823
Percentage of ContractwithCustomerAssetCurrentPeriodIncrease100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

ati:ContractwithCustomerAssetCurrentReclassification

ati:ContractwithCustomerAssetCurrentReclassification


Contractwith
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
Value1600000.03500000.0000-100000.0000000-16000000.0-800000.0
Percentage of ContractwithCustomerAssetCurrentReclassification100.0100.00.00.00.0100.00.00.00.00.00.00.0100.0100.0

ati:ContractwithCustomerAssetCurrentReclassifiedtoReceivable

ati:ContractwithCustomerAssetCurrentReclassifiedtoReceivable


Contractwith
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
Value1119311814201615212627202522
Percentage of ContractwithCustomerAssetCurrentReclassifiedtoReceivable100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

ati:ContractwithCustomerAssetNoncurrentReclassification

ati:ContractwithCustomerAssetNoncurrentReclassification


Contractwith
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value0.00.00.00.10.00.00.00.00.00.0160.8
Percentage of ContractwithCustomerAssetNoncurrentReclassification0.00.00.0100.00.00.00.00.00.00.0100.0100.0

ati:ContractwithCustomerLiabilityCurrentPeriodIncrease

ati:ContractwithCustomerLiabilityCurrentPeriodIncrease


Contractwith
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
Value205748232671214718382915238.4
Percentage of ContractwithCustomerLiabilityCurrentPeriodIncrease100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

ati:ContractwithCustomerLiabilityCurrentReclassification

ati:ContractwithCustomerLiabilityCurrentReclassification


Contractwith
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
Value100000.03200000.0-1700000.0-300000.0-2400000.0-3400000.0-4500000.00000-7200000.0-4900000.0-2500000.0
Percentage of ContractwithCustomerLiabilityCurrentReclassification100.0100.0100.0100.0100.0100.0100.00.00.00.00.0100.0100.0100.0

ati:ContractwithCustomerLiabilityCurrentReclassifiedtoRevenue

ati:ContractwithCustomerLiabilityCurrentReclassifiedtoRevenue


Contractwith
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-20900000.0-43000000.0-12000000.0-9000000.0-11800000.0-22100000.0-5300000.0900000.0-15500000.0-29300000.0-9500000.0-8400000.0-17600000.0-14100000.0
Percentage of ContractwithCustomerLiabilityCurrentReclassifiedtoRevenue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

ati:ContractwithCustomerLiabilityCurrentRevenueRecognized

ati:ContractwithCustomerLiabilityCurrentRevenueRecognized


Contractwith
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-14700000.0-4000000.0-24500000.0-27100000.0-21400000.0-17100000.0-41200000.0-20400000.0-11600000.0-2800000.0-19100000.0-15100000.0-8200000.0-300000.0
Percentage of ContractwithCustomerLiabilityCurrentRevenueRecognized100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

ati:ContractwithCustomerLiabilityNoncurrentPeriodIncrease

ati:ContractwithCustomerLiabilityNoncurrentPeriodIncrease


Contractwith
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
Value16242.00.55.07.4230.30.20.30.20.20.10.2
Percentage of ContractwithCustomerLiabilityNoncurrentPeriodIncrease100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

ati:ContractwithCustomerLiabilityNoncurrentReclassification

ati:ContractwithCustomerLiabilityNoncurrentReclassification


Contractwith
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
Value1.50.31.70.32.43.44.50.00.00.00.07.24.92.5
Percentage of ContractwithCustomerLiabilityNoncurrentReclassification100.0100.0100.0100.0100.0100.0100.00.00.00.00.0100.0100.0100.0

ati:ContractwithCustomerLiabilityNoncurrentReclassifiedtoRevenue

ati:ContractwithCustomerLiabilityNoncurrentReclassifiedtoRevenue


Contractwith
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-200000.0-300000.0-200000.0-300000.0-300000.0-200000.0-300000.0-300000.0-200000.0-300000.0-200000.0-300000.0-300000.0-200000.0
Percentage of ContractwithCustomerLiabilityNoncurrentReclassifiedtoRevenue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

ati:CorporateExpenses

ati:CorporateExpenses


Corporate
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
Value15129.5107.712161618161714121313141110109.8111111109.2111110.01111108.1-11.9-12.4-16.0-14.9-15.8-21.7-20.0-20.9-25.8-25.8-23.4-13.4-15.0-12.3
Percentage of CorporateExpenses100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

ati:EmployeeStockPlans

ati:EmployeeStockPlans


Employee
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-7.0-0.1-3.400000000000001-3.63.48.5-5.9-7.6-6.04.8-6.9-4.4-5.52.4-3.6-4.6-5.00.8-5.5-4.8-5.4-2.6-1.7-3.6-1.9-5.0-2.5-4.82.47.5-3.9-28.47.53.5-0.5149.9-13.3181212146.56.60.56.7
Percentage of EmployeeStockPlans100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

ati:EmployeeStockPlans us-gaap:StatementEquityComponents

us-gaap:AdditionalPaidInCapital


Employee
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-7.0-4.8-3.3-3.74.025-5.9-7.5-4.915-6.9-4.4-4.6-3.2-3.8-5.1-4.21.7-5.5-5.2-6.2-10.2-2.9-3.9-0.710.0-2.3-5.33.625-4.77.16.6-13.2-1.7138.3-45.718119.7-5.3116.40.1-12.9
Percentage of EmployeeStockPlans100.04800.097.1102.8117.6304.7100.098.781.7327.1100.0100.083.6-133.3105.6110.984.0212.5100.0108.3114.8392.3170.6108.336.8-200.092.0110.4150.0342.7120.5-25.088.0-377.1340.097.283.8343.6103.896.779.5-35.6180.097.020.0-192.5

us-gaap:RetainedEarnings


Employee
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
Value-0.10.10.20.00.00.00.30.00.00.00.20.00.00.00.90.0-0.10.21.80.20.30.50.47.10.00.20.4100.029-1.0-13.5-7.3-2.4-2.4-3.7-0.9-0.9-2.00.9-0.9-0.1-0.8-3.8
Percentage of EmployeeStockPlans2.9-2.85.90.0-0.0-0.0-5.00.0-0.0-0.0-3.60.0-0.0-0.0-18.00.01.8-4.2-33.3-7.7-17.6-13.9-21.1-142.0-0.0-4.216.7134.7-0.0-102.5-13.3-385.71460.0-17.0-24.227.8-4.9-7.3-16.46.0-13.8-1.5-160.0-56.7

us-gaap:TreasuryStock


Employee
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
Value0.04.70.00.0-0.8-17.40.0-0.1-1.4-10.90.00.0-1.15.60.20.5-1.7-0.90.10.2-1.07.40.9-0.2-1.6-22.1-0.20.3-1.6-28.30.8-64.61.9308.52.84.0360.21.34.519-4.30.31.223
Percentage of EmployeeStockPlans-0.0-4700.0-0.0-0.0-23.5-204.7-0.01.323.3-227.1-0.0-0.020.0233.3-5.6-10.934.0-112.5-1.8-4.218.5-284.6-52.95.684.2442.08.0-6.2-66.7-377.3-20.5227.525.3862.9-1700.019.940.4-271.41.110.636.9129.5-66.24.5240.0349.3

ati:InterestExpenseNet

ati:InterestExpenseNet


Interest
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value23232525212124242524252425253134343332323028292726262525282918181314151718192223232316161514
Percentage of InterestExpenseNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

ati:InterestExpenseNet us-gaap:DebtInstrument, us-gaap:LongtermDebtType

ati:AlleghenyTechnologiesConvertibleSeniorNotes35Due2025, us-gaap:ConvertibleDebt


Interest
Period End2021-06-30
Value-2.9
Percentage of InterestExpenseNet-12.2

ati:AlleghenyTechnologiesConvertibleSeniorNotes4.75Due2022, us-gaap:ConvertibleDebt


Interest
Period End2021-06-302020-06-30
Value-1.1-3.6
Percentage of InterestExpenseNet-4.6-16.6

ati:InventoryNetRealizableValueReservePeriodCharge

ati:InventoryNetRealizableValueReservePeriodCharge


Inventory
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-31
Value-7.3-6.83.0-6.52.01226-7.24.01.91.6-2.0-19.3-8.2-2.7-33.2-10.0-8.1-16.4-18.5-4.7-0.351764.8-0.5
Percentage of InventoryNetRealizableValueReservePeriodCharge100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

ati:Nonoperatingretirementbenefitexpense

ati:Nonoperatingretirementbenefitexpense


Nonoperatingretirementbenefitexpense
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
Value6.86.828111111181818188.48.48.88.313131313
Percentage of Nonoperatingretirementbenefitexpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

ati:OtherComprehensiveIncomeLossBeforeReclassificationAdjustmentsNetOfTaxAttributableToNoncontrollingInterest

ati:OtherComprehensiveIncomeLossBeforeReclassificationAdjustmentsNetOfTaxAttributableToNoncontrollingInterest


Other
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-31
Value1900000.0600000.06000000.0-500000.0-800000.0-4600000.0-3600000.05200000.0-9000000.0-3100000.06900000.05000000.0200000.02000000.0-1600000.0-1500000.0-1500000.0-4100000.0500000.0-200000.01800000.0-1200000.0-1800000.0100000.01900000.0500000.0
Percentage of OtherComprehensiveIncomeLossBeforeReclassificationAdjustmentsNetOfTaxAttributableToNoncontrollingInterest100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

ati:OtherComprehensiveIncomeLossBeforeReclassificationAdjustmentsNetOfTaxAttributableToNoncontrollingInterest us-gaap:StatementEquityComponents

us-gaap:AccumulatedTranslationAdjustment


Other
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-31
Value1900000.0600000.06000000.0-500000.0-800000.0-4600000.0-3600000.05200000.0-9000000.0-3100000.06900000.05000000.0200000.02000000.0-1600000.0-1500000.0-1500000.0-4100000.0500000.0-200000.01800000.0-1200000.0-1800000.0100000.01900000.0500000.0
Percentage of OtherComprehensiveIncomeLossBeforeReclassificationAdjustmentsNetOfTaxAttributableToNoncontrollingInterest100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

ati:OtherIncomeExpense

ati:OtherIncomeExpense


Other
Period End2020-09-302020-06-302019-09-302019-06-30
Value-1100000.02400000.0-8200000.0-7900000.0
Percentage of OtherIncomeExpense100.0100.0100.0100.0

ati:OtherNonoperatingIncomeExpenseOther

ati:OtherNonoperatingIncomeExpenseOther


Other
Period End2020-09-302020-06-302019-09-302019-06-30
Value-300000.0300000.0100000.00
Percentage of OtherNonoperatingIncomeExpenseOther100.0100.0100.00.0

ati:PaymentOfCappedCallTransactionsCost

ati:PaymentOfCappedCallTransactionsCost


Payment
Period End2020-12-312020-09-30
Value0.00.4
Percentage of PaymentOfCappedCallTransactionsCost0.0100.0

ati:PercentageOfForecastedNaturalGasUsageHedgedforYear1

ati:PercentageOfForecastedNaturalGasUsageHedgedforYear1


Percentage
Period End2021-06-302021-03-31
Value-5.075.0
Percentage of PercentageOfForecastedNaturalGasUsageHedgedforYear1100.0100.0

ati:PercentageOfForecastedNaturalGasUsageHedgedforYear2

ati:PercentageOfForecastedNaturalGasUsageHedgedforYear2


Percentage
Period End2021-06-302021-03-31
Value025.0
Percentage of PercentageOfForecastedNaturalGasUsageHedgedforYear20.0100.0

ati:PercentageOfRawMaterialUsageHedged

ati:PercentageOfRawMaterialUsageHedged


Percentage
Period End2021-06-302021-03-312020-12-31
Value010.00
Percentage of PercentageOfRawMaterialUsageHedged0.0100.00.0

ati:RentRoyaltyAndOtherIncome

ati:RentRoyaltyAndOtherIncome


Rent
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value200000.0300000.0300000.0100000.0200000.0300000.0100000.01400000.0700000.0700000.0800000.0600000.0900000.0
Percentage of RentRoyaltyAndOtherIncome100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

ati:Restructuringandothercharges

ati:Restructuringandothercharges


Restructuringandothercharges
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-06-302019-03-312017-12-312017-09-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-31
Value11052.3168.04.50.00.00.00.00.0284991.09.0890.00.00.0
Percentage of Restructuringandothercharges100.0100.0100.0100.0100.00.00.00.00.00.0100.0100.0100.0100.0100.00.00.00.0

ati:RevenuefromContractwithCustomerExcludingAssessedTaxPercentageofRevenue

ati:RevenuefromContractwithCustomerExcludingAssessedTaxPercentageofRevenue


Revenuefrom
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
Value100.0100.00100.01.01.001.01.01.001.01.01.001.01.01.0
Percentage of RevenuefromContractwithCustomerExcludingAssessedTaxPercentageofRevenue100.0100.00.0100.0100.0100.00.0100.0100.0100.00.0100.0100.0100.00.0100.0100.0100.0

ati:RevenuefromContractwithCustomerExcludingAssessedTaxPercentageofRevenue us-gaap:ConsolidationItems, us-gaap:ProductOrService, us-gaap:StatementBusinessSegments

us-gaap:OperatingSegments, ati:HighValueProducts, ati:AdvancedAlloysSolutions


Revenuefrom
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value90.081.09.074.00.720.77.073.00.720.7
Percentage of RevenuefromContractwithCustomerExcludingAssessedTaxPercentageofRevenue90.081.00.074.072.070.00.07300.072.070.0

us-gaap:OperatingSegments, ati:HighValueProducts, ati:HighPerformanceMaterialsComponents


Revenuefrom
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
Value100.0100.00100.01.01.001.01.01.001.01.01.001.01.01.0
Percentage of RevenuefromContractwithCustomerExcludingAssessedTaxPercentageofRevenue100.0100.00.0100.0100.0100.00.0100.0100.0100.00.0100.0100.0100.00.0100.0100.0100.0

us-gaap:OperatingSegments, ati:NickelbasedAlloysandSpecialtyAlloys, ati:AdvancedAlloysSolutions


Revenuefrom
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value21.028.04.022.00.260.257.029.00.30.23
Percentage of RevenuefromContractwithCustomerExcludingAssessedTaxPercentageofRevenue21.028.00.022.026.025.00.02900.030.023.0

us-gaap:OperatingSegments, ati:NickelbasedAlloysandSpecialtyAlloys, ati:HighPerformanceMaterialsComponents


Revenuefrom
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
Value45.036.0038.00.360.40.010.330.310.3100.320.320.290.010.30.310.3
Percentage of RevenuefromContractwithCustomerExcludingAssessedTaxPercentageofRevenue45.036.00.038.036.040.00.033.031.031.00.032.032.029.00.030.031.030.0

us-gaap:OperatingSegments, ati:PrecisionForgingsCastingandComponents, ati:HighPerformanceMaterialsComponents


Revenuefrom
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
Value36.043.0-1.030.00.350.35-0.010.290.320.32-0.010.330.350.3800.330.330.31
Percentage of RevenuefromContractwithCustomerExcludingAssessedTaxPercentageofRevenue36.043.00.030.035.035.00.029.032.032.00.033.035.038.00.033.033.031.0

us-gaap:OperatingSegments, ati:PrecisionandEngineeredStrip, ati:AdvancedAlloysSolutions


Revenuefrom
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-31
Value39.031.028.00.190.2122.00.210.23
Percentage of RevenuefromContractwithCustomerExcludingAssessedTaxPercentageofRevenue39.031.028.019.021.02200.021.023.0

us-gaap:OperatingSegments, ati:Standardstainlessproducts, ati:AdvancedAlloysSolutions


Revenuefrom
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-31
Value10.019.026.00.280.327.00.280.3
Percentage of RevenuefromContractwithCustomerExcludingAssessedTaxPercentageofRevenue10.019.026.028.030.02700.028.030.0

us-gaap:OperatingSegments, ati:TitaniumandTitaniumbasedAlloys, ati:AdvancedAlloysSolutions


Revenuefrom
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value6.07.0-1.08.00.130.11013.00.10.12
Percentage of RevenuefromContractwithCustomerExcludingAssessedTaxPercentageofRevenue6.07.00.08.013.011.00.01300.010.012.0

us-gaap:OperatingSegments, ati:TitaniumandTitaniumbasedAlloys, ati:HighPerformanceMaterialsComponents


Revenuefrom
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
Value19.021.01.032.00.290.2500.290.270.270.010.250.230.24-0.010.260.250.28
Percentage of RevenuefromContractwithCustomerExcludingAssessedTaxPercentageofRevenue19.021.00.032.029.025.00.029.027.027.00.025.023.024.00.026.025.028.0

us-gaap:OperatingSegments, ati:ZirconiumandRelatedAlloys, ati:AdvancedAlloysSolutions


Revenuefrom
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value24.015.02.016.00.140.13-1.09.00.110.12
Percentage of RevenuefromContractwithCustomerExcludingAssessedTaxPercentageofRevenue24.015.00.016.014.013.00.0900.011.012.0

ati:RevenuefromContractwithCustomerExcludingAssessedTaxPercentageofRevenue us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:OperatingSegments, ati:AdvancedAlloysSolutions


Revenuefrom
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value100.0100.00100.01.01.00100.01.01.0
Percentage of RevenuefromContractwithCustomerExcludingAssessedTaxPercentageofRevenue100.0100.00.0100.0100.0100.00.010000.0100.0100.0

us-gaap:OperatingSegments, ati:HighPerformanceMaterialsComponents


Revenuefrom
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
Value100.0100.00100.01.01.001.01.01.001.01.01.001.01.01.0
Percentage of RevenuefromContractwithCustomerExcludingAssessedTaxPercentageofRevenue100.0100.00.0100.0100.0100.00.0100.0100.0100.00.0100.0100.0100.00.0100.0100.0100.0

ati:RevenuefromContractwithCustomerExcludingAssessedTaxPercentageofRevenue us-gaap:ProductOrService

ati:HighValueProducts


Revenuefrom
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
Value95.088.04.084.00.830.8400.870.880.870.020.840.840.840.010.840.820.82
Percentage of RevenuefromContractwithCustomerExcludingAssessedTaxPercentageofRevenue95.088.00.084.083.084.00.087.088.087.00.084.084.084.00.084.082.082.0

ati:NickelbasedAlloysandSpecialtyAlloys


Revenuefrom
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
Value33.031.03.028.00.30.3200.330.330.300.30.30.290.010.280.270.26
Percentage of RevenuefromContractwithCustomerExcludingAssessedTaxPercentageofRevenue33.031.00.028.030.032.00.033.033.030.00.030.030.029.00.028.027.026.0

ati:PrecisionForgingsCastingandComponents


Revenuefrom
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
Value18.015.0011.00.140.1600.160.190.1900.180.20.2100.190.190.18
Percentage of RevenuefromContractwithCustomerExcludingAssessedTaxPercentageofRevenue18.015.00.011.014.016.00.016.019.019.00.018.020.021.00.019.019.018.0

ati:PrecisionandEngineeredStrip


Revenuefrom
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value19.020.018.00.120.1200.140.120.1300.140.130.1300.140.130.14
Percentage of RevenuefromContractwithCustomerExcludingAssessedTaxPercentageofRevenue19.020.018.012.012.00.014.012.013.00.014.013.013.00.014.013.014.0

ati:Standardstainlessproducts


Revenuefrom
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-31
Value5.012.016.00.170.1615.00.140.15
Percentage of RevenuefromContractwithCustomerExcludingAssessedTaxPercentageofRevenue5.012.016.017.016.01500.014.015.0

ati:TitaniumandTitaniumbasedAlloys


Revenuefrom
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
Value13.012.0-1.017.00.190.1700.190.180.190.020.160.160.1600.170.160.18
Percentage of RevenuefromContractwithCustomerExcludingAssessedTaxPercentageofRevenue13.012.00.017.019.017.00.019.018.019.00.016.016.016.00.017.016.018.0

ati:ZirconiumandRelatedAlloys


Revenuefrom
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
Value12.010.0010.00.080.0700.050.060.0600.060.050.0500.060.070.06
Percentage of RevenuefromContractwithCustomerExcludingAssessedTaxPercentageofRevenue12.010.00.010.08.07.00.05.06.06.00.06.05.05.00.06.07.06.0

ati:SegmentEarningsBeforeIncomeTaxesDepreciationAmortizationEBITDA

ati:SegmentEarningsBeforeIncomeTaxesDepreciationAmortizationEBITDA


Segment
Period End2021-06-302021-03-312020-06-302020-03-31
Value737462117
Percentage of SegmentEarningsBeforeIncomeTaxesDepreciationAmortizationEBITDA100.0100.0100.0100.0

ati:SegmentEarningsBeforeIncomeTaxesDepreciationAmortizationEBITDA us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:OperatingSegments, ati:AdvancedAlloysSolutions


Segment
Period End2021-06-302021-03-312020-06-302020-03-31
Value36493341
Percentage of SegmentEarningsBeforeIncomeTaxesDepreciationAmortizationEBITDA49.266.953.834.9

us-gaap:OperatingSegments, ati:HighPerformanceMaterialsComponents


Segment
Period End2021-06-302021-03-312020-06-302020-03-31
Value37242876
Percentage of SegmentEarningsBeforeIncomeTaxesDepreciationAmortizationEBITDA50.833.146.265.1

ati:SegmentOperatingProfitLoss

ati:SegmentOperatingProfitLoss


Segment
Period End2020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-30
Value-6.82781105991146187105124968854706953267.0-80.5-99.1-73.0398367706543-10.9277178951191591631141611731628863
Percentage of SegmentOperatingProfitLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

ati:SegmentOperatingProfitLoss us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:OperatingSegments, ati:AdvancedAlloysSolutions


Segment
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-31
Value-4.11824303610.0
Percentage of SegmentOperatingProfitLoss60.366.329.731.031.516.2

us-gaap:OperatingSegments, ati:HighPerformanceMaterialsComponents


Segment
Period End2020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value-2.79.257927898727676978565616850
Percentage of SegmentOperatingProfitLoss39.733.770.388.179.486.4117.787.172.079.088.774.6113.495.972.8

ati:StrikeRelatedCosts

ati:StrikeRelatedCosts


Strike
Period End2021-06-30
Value40
Percentage of StrikeRelatedCosts100.0

ati:StrikeRelatedCosts us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:OperatingSegments, ati:AdvancedAlloysSolutions


Strike
Period End2021-06-30
Value38
Percentage of StrikeRelatedCosts94.8

us-gaap:OperatingSegments, ati:HighPerformanceMaterialsComponents


Strike
Period End2021-06-30
Value2.1
Percentage of StrikeRelatedCosts5.2

us-gaap:AdjustmentsToAdditionalPaidInCapitalEquityComponentOfConvertibleDebt

us-gaap:AdjustmentsToAdditionalPaidInCapitalEquityComponentOfConvertibleDebt


Adjustments
Period End2020-12-312020-09-302020-06-30
Value0.01.148
Percentage of AdjustmentsToAdditionalPaidInCapitalEquityComponentOfConvertibleDebt0.0100.0100.0

us-gaap:AdjustmentsToAdditionalPaidInCapitalEquityComponentOfConvertibleDebt us-gaap:StatementEquityComponents

us-gaap:AdditionalPaidInCapital


Adjustments
Period End2020-12-312020-09-302020-06-30
Value0.01.148
Percentage of AdjustmentsToAdditionalPaidInCapitalEquityComponentOfConvertibleDebt0.0100.0100.0

us-gaap:AllowanceForDoubtfulAccountsReceivableWriteOffs

us-gaap:AllowanceForDoubtfulAccountsReceivableWriteOffs


Allowance
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
Value100000.0300000.0100000.0100000.00300000.0300000.0300000.0600000.0400000.01400000.00100000.0300000.0
Percentage of AllowanceForDoubtfulAccountsReceivableWriteOffs100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.00.0100.0100.0

us-gaap:AssetRetirementObligationRevisionOfEstimate

us-gaap:AssetRetirementObligationRevisionOfEstimate


Asset
Period End2020-12-312020-09-302020-06-302019-06-30
Value-4.50.04.30.0
Percentage of AssetRetirementObligationRevisionOfEstimate100.00.0100.00.0

us-gaap:CapitalExpendituresIncurredButNotYetPaid

us-gaap:CapitalExpendituresIncurredButNotYetPaid


Capital
Period End2021-06-302021-03-31
Value-5800000.09200000.0
Percentage of CapitalExpendituresIncurredButNotYetPaid100.0100.0

us-gaap:CapitalizedContractCostAmortization

us-gaap:CapitalizedContractCostAmortization


Capitalized
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
Value300000.0200000.0300000.0400000.0400000.0300000.0400000.0400000.0300000.0300000.0300000.0300000.0300000.0300000.0
Percentage of CapitalizedContractCostAmortization100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:CashFlowHedgeGainLossToBeReclassifiedWithinTwelveMonths

us-gaap:CashFlowHedgeGainLossToBeReclassifiedWithinTwelveMonths


Cash
Period End2021-06-302021-03-312020-12-31
Value4700000.0700000.0800000.0
Percentage of CashFlowHedgeGainLossToBeReclassifiedWithinTwelveMonths100.0100.0100.0

us-gaap:DebtInstrumentConvertibleConversionRatio1 us-gaap:DebtInstrument, us-gaap:LongtermDebtType

us-gaap:DebtInstrumentConvertibleConversionRatio1

ati:AlleghenyTechnologiesConvertibleSeniorNotes35Due2025, us-gaap:ConvertibleDebt


Debt
Period End2021-06-302021-03-312020-09-30
Value00.0645750.064575
Percentage of DebtInstrumentConvertibleConversionRatio10.0100.0100.0

ati:AlleghenyTechnologiesConvertibleSeniorNotes4.75Due2022, us-gaap:ConvertibleDebt


Debt
Period End2021-06-302021-03-312016-06-02
Value00.0692040.069204
Percentage of DebtInstrumentConvertibleConversionRatio10.0107.20.0

us-gaap:DebtInstrumentConvertibleNumberOfEquityInstruments us-gaap:DebtInstrument, us-gaap:LongtermDebtType

us-gaap:DebtInstrumentConvertibleNumberOfEquityInstruments

ati:AlleghenyTechnologiesConvertibleSeniorNotes35Due2025, us-gaap:ConvertibleDebt


Debt
Period End2021-06-302021-03-31
Value0.018
Percentage of DebtInstrumentConvertibleNumberOfEquityInstruments0.0100.0

ati:AlleghenyTechnologiesConvertibleSeniorNotes4.75Due2022, us-gaap:ConvertibleDebt


Debt
Period End2021-06-302021-03-31
Value0.05.8
Percentage of DebtInstrumentConvertibleNumberOfEquityInstruments0.030.9

us-gaap:DeferredIncomeTaxesAndTaxCredits

us-gaap:DeferredIncomeTaxesAndTaxCredits


Deferred
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
Value1.4-0.4-28.60.4898.3-45.01.41.11.6-0.72.70.3-0.2-3.1-5.96.41.2-41.7-15.7-23.7-38.7-127.619-14.65.0164.512-1.7-6.019213613-15.3-5.6-12.02243-10.7-2.432341124
Percentage of DeferredIncomeTaxesAndTaxCredits100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DefinedBenefitPlanAmortizationOfGainsLosses us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanAmortizationOfGainsLosses

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit


Defined
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-30
Value-3300000.0-3300000.0-2700000.0-2700000.0-2700000.0-2700000.0-3400000.0-3400000.0-3400000.0-3300000.0-2600000.0-2700000.0-2600000.0-2700000.0-2300000.0-2200000.0-2300000.0-2200000.0-2400000.0-2400000.0-2400000.0
Percentage of DefinedBenefitPlanAmortizationOfGainsLosses100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-30
Value-18900000.0-18900000.0-18700000.0-18600000.0-18600000.0-18600000.0-18400000.0-18500000.0-18400000.0-18400000.0-16400000.0-16500000.0-16500000.0-16500000.0-15700000.0-15600000.0-15700000.0-15600000.0-16400000.0-16300000.0-16400000.0
Percentage of DefinedBenefitPlanAmortizationOfGainsLosses572.7572.7692.6688.9688.9688.9541.2544.1541.2557.6630.8611.1634.6611.1682.6709.1682.6709.1683.3679.2683.3

us-gaap:DefinedBenefitPlanAmortizationOfPriorServiceCostCredit us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanAmortizationOfPriorServiceCostCredit

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit


Defined
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-30
Value-0.6-0.7-1.0-0.9-1.0-0.9-0.8-0.7-0.7-0.7-0.7-0.8-0.7-0.7-0.8-0.7-0.7-0.7-0.8-0.7-0.8
Percentage of DefinedBenefitPlanAmortizationOfPriorServiceCostCredit100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-30
Value0.10.20.20.10.20.20.10.00.10.10.00.10.10.10.40.30.30.30.40.30.3
Percentage of DefinedBenefitPlanAmortizationOfPriorServiceCostCredit-16.7-28.6-20.0-11.1-20.0-22.2-12.5-0.0-14.3-14.3-0.0-12.5-14.3-14.3-50.0-42.9-42.9-42.9-50.0-42.9-37.5

us-gaap:DefinedBenefitPlanBenefitObligationIncreaseDecreaseForRemeasurementDueToSettlement us-gaap:StatementScenario, us-gaap:CollectiveBargainingArrangement, us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanBenefitObligationIncreaseDecreaseForRemeasurementDueToSettlement

srt:ScenarioForecast, us-gaap:CollectiveBargainingArrangementOther, us-gaap:OtherPostretirementBenefitPlansDefinedBenefit


Defined
Period End2021-09-30
Value65
Percentage of DefinedBenefitPlanBenefitObligationIncreaseDecreaseForRemeasurementDueToSettlement100.0

us-gaap:DefinedBenefitPlanCostOfProvidingSpecialOrContractualTerminationBenefitRecognizedDuringPeriod

us-gaap:DefinedBenefitPlanCostOfProvidingSpecialOrContractualTerminationBenefitRecognizedDuringPeriod


Defined
Period End2020-12-31
Value17
Percentage of DefinedBenefitPlanCostOfProvidingSpecialOrContractualTerminationBenefitRecognizedDuringPeriod100.0

us-gaap:DefinedBenefitPlanExpectedReturnOnPlanAssets us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanExpectedReturnOnPlanAssets

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-30
Value343433333333323232323939393936363636373737
Percentage of DefinedBenefitPlanExpectedReturnOnPlanAssets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DefinedBenefitPlanInterestCost us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanInterestCost

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit


Defined
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-30
Value2.12.12.72.62.72.73.73.73.73.73.23.23.23.13.63.73.63.74.04.03.9
Percentage of DefinedBenefitPlanInterestCost100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-30
Value171721212121262626262626262629292929313131
Percentage of DefinedBenefitPlanInterestCost814.3814.3800.0830.8800.0796.3713.5713.5713.5710.8821.9818.8821.9841.9808.3789.2811.1789.2782.5785.0802.6

us-gaap:DefinedBenefitPlanNetPeriodicBenefitCost us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanNetPeriodicBenefitCost

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit


Defined
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-30
Value5.25.0115.05.05.06.86.96.86.85.85.75.75.75.75.85.85.88.56.36.2
Percentage of DefinedBenefitPlanNetPeriodicBenefitCost100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-30
Value5.75.9209.99.99.9151515157.37.47.87.412111211171616
Percentage of DefinedBenefitPlanNetPeriodicBenefitCost109.6118.0181.7198.0198.0198.0225.0221.7222.1223.5125.9129.8136.8129.8210.5205.2206.9205.2201.2254.0258.1

us-gaap:DefinedBenefitPlanServiceCost us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanServiceCost

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit


Defined
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-30
Value0.40.30.60.60.60.50.50.50.40.50.70.60.60.60.60.60.60.60.70.60.7
Percentage of DefinedBenefitPlanServiceCost100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-30
Value3.73.83.23.23.13.23.23.23.13.24.04.14.04.23.63.53.53.55.15.25.1
Percentage of DefinedBenefitPlanServiceCost925.01266.7533.3533.3516.7640.0640.0640.0775.0640.0571.4683.3666.7700.0600.0583.3583.3583.3728.6866.7728.6

us-gaap:DerivativeInstrumentsGainLossReclassifiedFromAccumulatedOCIIntoIncomeEffectivePortionNet us-gaap:DerivativeInstrumentRisk, us-gaap:DerivativeInstrumentsGainLossByHedgingRelationship, us-gaap:IncomeStatementLocation

us-gaap:DerivativeInstrumentsGainLossReclassifiedFromAccumulatedOCIIntoIncomeEffectivePortionNet

ati:NaturalGasContracts, us-gaap:CashFlowHedging, us-gaap:CostOfSales


Derivative
Period End2021-06-302020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-30
Value0.20.0-0.8-1.0-1.0-0.3-0.6-0.10.10.80.0-0.1-0.3-0.5-0.7-0.7-1.4-1.2-1.3-2.7-3.2-2.8-1.6-2.4-2.4-0.30.01.01.4-0.8-0.60.1-1.0-1.3-1.8-2.4-2.6-3.6-2.7
Percentage of DerivativeInstrumentsGainLossReclassifiedFromAccumulatedOCIIntoIncomeEffectivePortionNet100.00.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

ati:NickelAndOtherRawMaterialContracts, us-gaap:CashFlowHedging, us-gaap:CostOfSales


Derivative
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-30
Value1.11.50.70.7-1.8-0.23.41.1-0.2-0.4-0.21.73.42.80.4-0.9-1.0-0.6-2.2-2.2-3.8-3.9-3.5-2.4-2.4-2.2-1.11.30.9-1.7-3.1-1.3-1.10.1-1.1-1.5-0.7-0.1-2.6-2.5
Percentage of DerivativeInstrumentsGainLossReclassifiedFromAccumulatedOCIIntoIncomeEffectivePortionNet550.00.00.0-87.5180.020.0-1133.3-183.3200.0-400.0-25.00.0-3400.0-933.3-80.0128.6142.942.9183.3169.2140.7121.9125.0150.0100.091.7366.70.090.0-121.4387.5216.7-1100.0-10.084.683.329.23.872.292.6

us-gaap:ForeignExchangeContract, us-gaap:CashFlowHedging, us-gaap:CostOfSales


Derivative
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-30
Value0.00.0-0.10.00.50.30.0-0.30.60.40.2-0.22.42.42.52.63.43.44.94.75.86.06.16.43.00.4-1.7-1.4-1.3-0.70.60.71.53.53.21.91.5-0.2
Percentage of DerivativeInstrumentsGainLossReclassifiedFromAccumulatedOCIIntoIncomeEffectivePortionNet0.0-0.010.0-0.0-166.7-50.0-0.0-300.075.00.0-200.066.7-480.0-342.9-357.1-185.7-283.3-261.5-181.5-146.9-207.1-375.0-254.2-266.7-1000.00.0-170.0-100.0162.5116.7600.0-70.0-115.4-194.4-133.3-73.1-41.77.4

us-gaap:InterestRateSwap, us-gaap:CashFlowHedging, us-gaap:InterestExpense


Derivative
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value-0.2-0.2-0.4-0.2-0.3-0.2-0.1-0.1-0.1-0.1-0.1-0.10.00.00.00.0
Percentage of DerivativeInstrumentsGainLossReclassifiedFromAccumulatedOCIIntoIncomeEffectivePortionNet-100.00.00.025.030.020.033.316.7100.0-100.0-12.50.0-0.0-0.0-0.0-0.0

us-gaap:DerivativeInstrumentsGainLossReclassifiedFromAccumulatedOCIIntoIncomeEffectivePortionNet us-gaap:DerivativeInstrumentsGainLossByHedgingRelationship, us-gaap:IncomeStatementLocation

us-gaap:CashFlowHedging, ati:CostofSalesandInterestExpense


Derivative
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-30
Value1.11.30.3-0.3-3.2-1.43.50.7-0.4-0.71.12.0
Percentage of DerivativeInstrumentsGainLossReclassifiedFromAccumulatedOCIIntoIncomeEffectivePortionNet550.00.00.037.5320.0140.0-1166.7-116.7400.0-700.0137.50.0

us-gaap:DerivativeNonmonetaryNotionalAmountMass us-gaap:DerivativeInstrumentRisk

us-gaap:DerivativeNonmonetaryNotionalAmountMass

ati:Nickel


Derivative
Period End2021-06-302021-03-312020-12-31
Value-1000000.06000000.00
Percentage of DerivativeNonmonetaryNotionalAmountMass100.0100.00.0

us-gaap:GainLossOnDispositionOfAssets1

us-gaap:GainLossOnDispositionOfAssets1


Gain
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value1.21.2-0.40.80.02.50.16229-0.80.80.10.4
Percentage of GainLossOnDispositionOfAssets1100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:GainLossOnSaleOfProperty

us-gaap:GainLossOnSaleOfProperty


Gain
Period End2020-09-302020-06-302020-03-312019-12-312019-09-302019-06-30
Value0.00.02.50.06229
Percentage of GainLossOnSaleOfProperty0.00.0100.00.0100.0100.0

us-gaap:GainLossOnSaleOfPropertyPlantEquipment

us-gaap:GainLossOnSaleOfPropertyPlantEquipment


Gain
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-30
Value1.21.2-0.40.80.02.50.06229-0.80.70.1
Percentage of GainLossOnSaleOfPropertyPlantEquipment100.0100.0100.0100.00.0100.00.0100.0100.0100.0100.0100.0

us-gaap:GainLossOnSalesOfAssetsAndAssetImpairmentCharges

us-gaap:GainLossOnSalesOfAssetsAndAssetImpairmentCharges


Gain
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value0.00.00.02.50.068210.00.00.00.0
Percentage of GainLossOnSalesOfAssetsAndAssetImpairmentCharges0.00.00.0100.00.0100.0100.00.00.00.00.0

us-gaap:GoodwillImpairmentLoss

us-gaap:GoodwillImpairmentLoss


Goodwill
Period End2020-12-312020-09-302020-06-302019-06-302018-12-312018-09-302017-12-312017-09-302016-12-312016-09-30
Value0.00.02870.00.00.00.01140.00.0
Percentage of GoodwillImpairmentLoss0.00.0100.00.00.00.00.0100.00.00.0

us-gaap:GoodwillPeriodIncreaseDecrease

us-gaap:GoodwillPeriodIncreaseDecrease


Goodwill
Period End2020-12-31
Value2300000.0
Percentage of GoodwillPeriodIncreaseDecrease100.0

us-gaap:IncomeLossFromEquityMethodInvestments

us-gaap:IncomeLossFromEquityMethodInvestments


Income
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value-400000.0-1000000.0-1900000.0-3700000.0-2000000.0-2400000.0-3500000.0-2800000.0-3500000.0200000.02300000.0
Percentage of IncomeLossFromEquityMethodInvestments100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncomeLossFromEquityMethodInvestments us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName, us-gaap:RestructuringCostAndReserve

ati:AlleghenyTsingshanStainless, us-gaap:EmployeeSeverance


Income
Period End2020-09-302020-06-302019-06-30
Value0-2400000.00
Percentage of IncomeLossFromEquityMethodInvestments-0.0126.3-0.0

us-gaap:IncomeLossFromEquityMethodInvestments us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName, us-gaap:StatementBusinessSegments

ati:AlleghenyTsingshanStainless, ati:AdvancedAlloysSolutions


Income
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value-400000.0-500000.01900000.0-1600000.0-4600000.0-3900000.0-2300000.0-2600000.0-4000000.0-3300000.0
Percentage of IncomeLossFromEquityMethodInvestments0.00.0-475.0160.0242.1105.4115.0108.3114.3117.9

ati:Uniti, ati:AdvancedAlloysSolutions


Income
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value400000.0500000.0100000.0600000.0300000.0200000.0300000.0200000.0500000.0500000.0
Percentage of IncomeLossFromEquityMethodInvestments0.00.0-25.0-60.0-15.8-5.4-15.0-8.3-14.3-17.9

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
Value-59.03450-35.1-148.9-96.51052.3-34.0-43.582-13.34.57969-2.011479.0-22.95.9-43.2-21.6-120.4-72.02.774-74.2364569-23.2-33.8-20.490-42.4-54.215-1.1-11.4-48.6111-17.948-33.288
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:IncreaseDecreaseInPensionAndPostretirementObligations

us-gaap:IncreaseDecreaseInPensionAndPostretirementObligations


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
Value1.400000000000002-16.6-13.6-61.36.0-23.0-17.3-51.8-15.8-18.4-22.5-13.02.40.57.317-6.9-128.114-104.92.97.46.42.92.52.5-16.28.46.74.220181516181315117.06.12.73.8118.49.05.6
Percentage of IncreaseDecreaseInPensionAndPostretirementObligations100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:InterestExpenseDebtExcludingAmortization us-gaap:DebtInstrument, us-gaap:LongtermDebtType

us-gaap:InterestExpenseDebtExcludingAmortization

ati:AlleghenyTechnologiesConvertibleSeniorNotes35Due2025, us-gaap:ConvertibleDebt


Interest
Period End2021-06-30
Value2500000.0
Percentage of InterestExpenseDebtExcludingAmortization100.0

ati:AlleghenyTechnologiesConvertibleSeniorNotes4.75Due2022, us-gaap:ConvertibleDebt


Interest
Period End2021-06-302020-06-30
Value1000000.03200000.0
Percentage of InterestExpenseDebtExcludingAmortization40.00.0

us-gaap:InventoryLIFOReservePeriodCharge

us-gaap:InventoryLIFOReservePeriodCharge


Inventory
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-31
Value7.36.8-3.06.5-2.0-12.0-26.97.2-4.0-1.8-0.92.0198.22.733108.116184.30.3-51.3-75.8-5.00.5
Percentage of InventoryLIFOReservePeriodCharge100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:LineOfCreditFacilityAverageOutstandingAmount us-gaap:DebtInstrument

us-gaap:LineOfCreditFacilityAverageOutstandingAmount

ati:DomesticBankGroup500millionassetbasedcreditfacility


Line
Period End2020-12-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-31
Value-10.0-20.05.0530.00.00.0
Percentage of LineOfCreditFacilityAverageOutstandingAmount100.0100.0100.0100.00.00.00.0

us-gaap:LineOfCreditFacilityInterestRateDuringPeriod us-gaap:DebtInstrument

us-gaap:LineOfCreditFacilityInterestRateDuringPeriod

ati:DomesticBankGroup500millionassetbasedcreditfacility


Line
Period End2020-12-312020-09-302020-06-302020-03-31
Value00-0.42.6
Percentage of LineOfCreditFacilityInterestRateDuringPeriod0.00.0100.0100.0

us-gaap:OtherAssetImpairmentCharges

us-gaap:OtherAssetImpairmentCharges


Other
Period End2020-12-31
Value1041
Percentage of OtherAssetImpairmentCharges100.0

us-gaap:OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditBeforeTax

us-gaap:OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditBeforeTax


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
Value-0.5-0.5-0.8-0.8-0.8-0.7-0.7-0.7-0.6-0.6-0.7-0.7-0.6-0.6-0.4-0.4-0.4-0.4-0.4-0.4-0.50.91.71.51.51.5-0.2-0.2-0.1-0.2-3.8-3.8-3.8-3.8
Percentage of OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditBeforeTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditBeforeTax us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:StatementEquityComponents

us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:AccumulatedDefinedBenefitPlansAdjustment


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
Value0.50.50.80.80.80.70.70.70.60.60.70.70.60.60.40.40.40.40.40.40.5-0.9-1.7-1.5-1.5-1.50.20.20.10.23.83.83.83.8
Percentage of OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditBeforeTax-100.0-100.0-100.0-100.0-100.0-100.0-100.0-100.0-100.0-100.0-100.0-100.0-100.0-100.0-100.0-100.0-100.0-100.0-100.0-100.0-100.0-100.0-100.0-100.0-100.0-100.0-100.0-100.0-100.0-100.0-100.0-100.0-100.0-100.0

us-gaap:OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax

us-gaap:OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
Value10-5.1-86.42116-32.0-140.4-1.1-9.213-123.2-12.9-15.619-20.7240.15.8-142.90.28.04.3-95.2-28.612-10.2-290.2-1.2164.22471.3-7.3-5.4
Percentage of OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax us-gaap:StatementEquityComponents

us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedges


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
Value5.10.31.14.71.6-9.4-6.910-4.38.0-6.8-8.17.52.5125.7-5.2-1.5-0.43.016-5.7-9.2-16.5-6.411-2.7177.95.7-2.6-11.1-9.88.0
Percentage of OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax50.0-5.9-1.321.59.829.44.9-963.646.758.05.562.8-48.113.0-58.522.9-5200.0-25.90.31500.0203.8-132.69.757.7-52.0-111.80.9-1433.346.7135.7-1.1-853.8134.2-148.1

us-gaap:AccumulatedTranslationAdjustment


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
Value5.1-5.4111714-22.68.1-11.7-4.95.8-9.2-4.8-23.116-0.3194.28.4-22.4-2.8-8.3-3.9-16.5-12.118-21.6-21.0-18.48.9-1.59.0122.6-13.5
Percentage of OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax50.0105.9-13.778.590.270.6-5.81063.653.342.07.537.2148.187.01.477.14200.0144.815.7-1400.0-103.8-90.717.342.3152.8211.87.21533.352.7-35.73.6946.2-35.6250.0

us-gaap:OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesNetOfTax

us-gaap:OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesNetOfTax


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
Value5.5-1.31.06.53.7-8.0-9.413-5.211-10.2-13.45.20.3123.2-4.6-3.50.73.418-2.6-15.5-18.5-7.79.7-4.3157.67.02.6-8.5-9.48.4-8.35.110-9.76.79.7
Percentage of OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToNoncontrollingInterest

us-gaap:OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToNoncontrollingInterest


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
Value1.90.66.76.0-0.5-0.81.7-4.6-3.65.2-1.0-9.0-3.16.90.45.00.22.0-5.1-1.6-1.5-1.5-1.8-4.10.5-0.2-0.91.8-1.2-1.80.90.11.90.5
Percentage of OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToNoncontrollingInterest100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToNoncontrollingInterest us-gaap:StatementEquityComponents

us-gaap:AccumulatedTranslationAdjustment


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
Value1.90.66.76.0-0.5-0.81.7-4.6-3.65.2-1.0-9.0-3.16.90.45.00.22.0-5.1-1.6-1.5-1.5-1.8-4.10.5-0.2-0.91.8-1.2-1.80.90.11.90.5
Percentage of OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToNoncontrollingInterest100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent

us-gaap:OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
Value3215-95.04443-14.9-140.3231138-142.50.30.635-11.5504.222-132.0122119-89.1-18.1230.6-277.8103018269221113
Percentage of OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent us-gaap:StatementEquityComponents

ati:AccumulatedDeferredTaxAssetValuationAllowance


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-31
Value6.74.9-23.96.48.70.0-12.28.73.67.7-31.81.25.74.40.516-5.25.2-45.60.00.00.0
Percentage of OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent20.732.725.214.519.9-0.08.737.832.420.122.3400.0950.012.4-4.332.0-123.823.334.50.00.00.0

us-gaap:AccumulatedDefinedBenefitPlansAdjustment


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
Value1616-83.7151515-125.8161616-93.6141414-21.5101110-63.2111126-57.2121212-252.9131313256181818
Percentage of OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent51.1110.088.135.335.6-105.489.770.0146.842.065.74666.72333.340.2187.020.6266.748.447.995.053.8133.264.2-69.153.22083.391.0126.444.970.995.182.4160.5137.9

us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedges


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
Value4.0-1.00.85.04.8-8.0-10.49.9-3.98.7-7.9-10.14.00.29.84.9-6.0-2.1-0.83.418-2.6-15.5-18.5-7.79.7-4.3157.67.02.6-8.5-9.48.4
Percentage of OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent12.4-6.7-0.811.311.053.77.443.0-35.122.75.5-3366.7666.70.6-85.29.6-142.9-9.40.628.385.4-13.317.4102.2-32.81616.71.5147.225.237.01.0-38.3-82.563.6

us-gaap:AccumulatedTranslationAdjustment


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
Value5.1-5.4111714-22.68.1-11.7-4.95.8-9.2-4.8-23.116-0.3194.28.4-22.4-2.8-8.3-3.9-16.5-12.118-21.6-20.5-18.48.9-1.510122.6-13.5
Percentage of OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent15.8-36.0-12.438.933.6151.7-5.8-50.9-44.115.16.5-1600.0-3850.046.92.637.7100.037.717.0-23.3-39.2-19.918.566.980.0-3600.07.4-173.629.6-7.93.955.422.8-102.3

us-gaap:OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax

us-gaap:OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax


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-21.7-21.7107-20.5-25.4-15.7139-21.2-21.2-21.1123-18.5-18.5-18.623-28.5-4.6-17.4110-11.4-11.4-26.157-12.5-12.5-12.5252-13.4-13.5-13.4-256.3-18.3-18.3-18.24716-16.6-16.72458.7
Percentage of OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIOnDerivativesBeforeTax

us-gaap:OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIOnDerivativesBeforeTax


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
Value1.51.70.4-0.4-4.2-1.84.70.8-0.5-0.91.42.64.73.03.71.21.40.90.6-0.6-2.9-5.0103.32.12.72.62.60.5-2.1-8.5-4.3-0.5-0.7
Percentage of OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIOnDerivativesBeforeTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossBeforeTax

us-gaap:OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossBeforeTax


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
Value-22.2-22.2-21.4-21.3-21.3-21.3-21.8-21.9-21.8-21.7-19.0-19.2-19.1-19.2-18.0-17.8-18.0-17.8-18.8-18.7-18.8-18.7-18.8-18.8-18.7-18.7-22.0-22.1-22.0-22.0-28.5-33.5-33.5-33.5
Percentage of OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossBeforeTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossBeforeTax us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:StatementEquityComponents

us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:AccumulatedDefinedBenefitPlansAdjustment


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
Value22222121212121212121191919191817181718181818181818182222222228333333
Percentage of OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossBeforeTax-100.0-100.0-100.0-100.0-100.0-100.0-100.0-100.0-100.0-100.0-100.0-100.0-100.0-100.0-100.0-100.0-100.0-100.0-100.0-100.0-100.0-100.0-100.0-100.0-100.0-100.0-100.0-100.0-100.0-100.0-100.0-100.0-100.0-100.0

us-gaap:OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodBeforeTax

us-gaap:OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodBeforeTax


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
Value7.00.41.46.12.0-12.3-9.414-5.710-8.8-10.89.93.3159.2-8.2-2.6-0.74.826-9.2-14.6-26.8-10.418-4.428129.3-4.2-18.1-16.013-15.37.815-18.2
Percentage of OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodBeforeTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodBeforeTax us-gaap:DerivativeInstrumentRisk, us-gaap:DerivativeInstrumentsGainLossByHedgingRelationship, us-gaap:IncomeStatementLocation

ati:NaturalGasContracts, us-gaap:CashFlowHedging, us-gaap:OtherComprehensiveIncome


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-30
Value2.00.4-1.32.5-0.1-1.2-0.8-0.9-1.9-0.41.4-0.10.00.2-0.70.0-0.5
Percentage of OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodBeforeTax28.6100.0-92.941.0-5.09.88.5-6.333.3-3.8-15.90.90.06.1-4.40.06.1

ati:NickelAndOtherRawMaterialContracts, us-gaap:CashFlowHedging, us-gaap:OtherComprehensiveIncome


Other
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-30
Value3.4-0.62.12.0-6.2-6.911-1.98.3-7.7-8.06.23.1125.6-4.6
Percentage of OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodBeforeTax48.6-150.034.4100.050.473.482.533.379.087.574.162.693.981.160.956.1

us-gaap:ForeignExchangeContract, us-gaap:CashFlowHedging, us-gaap:OtherComprehensiveIncome


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-30
Value0.00.10.00.00.0-0.10.00.9-0.20.3-0.20.21.3-0.8-0.10.1-0.1
Percentage of OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodBeforeTax0.025.00.00.00.00.8-0.06.33.52.92.3-1.913.1-24.2-0.61.11.2

us-gaap:InterestRateSwap, us-gaap:CashFlowHedging, us-gaap:OtherComprehensiveIncome


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value-0.30.40.30.1-0.3-1.90.8-1.2-0.3-0.2-0.3-0.20.00.00.00.0
Percentage of OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodBeforeTax-4.3100.021.41.6-15.015.4-8.5-8.45.3-1.93.41.90.00.00.00.0

us-gaap:OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodBeforeTax us-gaap:DerivativeInstrumentsGainLossByHedgingRelationship, us-gaap:IncomeStatementLocation

us-gaap:CashFlowHedging, us-gaap:OtherComprehensiveIncome


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-30
Value5.10.31.14.71.6-9.4-6.910-4.38.0-6.8-8.17.52.5125.7-5.2
Percentage of OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodBeforeTax72.975.078.677.080.076.473.474.175.476.277.375.075.875.876.162.063.4

us-gaap:OtherOperatingIncomeExpenseNet

us-gaap:OtherOperatingIncomeExpenseNet


Other
Period End2021-06-302021-03-312020-06-302020-03-31
Value3600000.0-500000.0-2700000.06300000.0
Percentage of OtherOperatingIncomeExpenseNet100.0100.0100.0100.0

us-gaap:OtherRestructuringCosts

us-gaap:OtherRestructuringCosts


Other
Period End2020-12-31
Value12
Percentage of OtherRestructuringCosts100.0

us-gaap:PaymentsForProceedsFromOtherInvestingActivities

us-gaap:PaymentsForProceedsFromOtherInvestingActivities


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
Value0100000.0-500000.0-400000.00-1000000.00100000.00100000.0-1900000.0-1400000.0-700000.0-100000.0100000.0100000.0-700000.0-2600000.0-100000.0-300000.0-1000000.0-800000.0100000.00100000.0-100000.0-500000.0200000.0-300000.0-1800000.00-300000.0200000.0-700000.0-1800000.0-600000.00-900000.0300000.0-400000.0-2100000.0-500000.0-1500000.0200000.0-400000.0-600000.0
Percentage of PaymentsForProceedsFromOtherInvestingActivities0.0100.0100.0100.00.0100.00.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PaymentsForRepurchaseOfOtherEquity

us-gaap:PaymentsForRepurchaseOfOtherEquity


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
Value0.04.70.00.00.07.80.00.00.09.90.00.00.06.50.00.00.04.80.00.00.00.00.00.00.01.40.00.00.03.90.00.0-0.16.70.00.10.0230.90.00.01.30.20.00.00.7
Percentage of PaymentsForRepurchaseOfOtherEquity0.0100.00.00.00.0100.00.00.00.0100.00.00.00.0100.00.00.00.0100.00.00.00.00.00.00.00.0100.00.00.00.0100.00.00.0100.0100.00.0100.00.0100.0100.00.00.0100.0100.00.00.0100.0

us-gaap:PaymentsForRestructuring

us-gaap:PaymentsForRestructuring


Payments
Period End2021-06-302021-03-312016-12-31
Value3.76.511
Percentage of PaymentsForRestructuring100.0100.0100.0

us-gaap:PaymentsOfDebtExtinguishmentCosts

us-gaap:PaymentsOfDebtExtinguishmentCosts


Payments
Period End2020-12-312020-09-302020-06-30
Value0.00.019
Percentage of PaymentsOfDebtExtinguishmentCosts0.00.0100.0

us-gaap:PaymentsOfDebtIssuanceCosts

us-gaap:PaymentsOfDebtIssuanceCosts


Payments
Period End2020-12-312020-09-302018-12-312018-09-302017-12-312017-09-302016-12-312016-09-302015-12-312015-09-302014-12-312013-12-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value0.01.00.00.00.00.00.00.00.00.01.20.00.00.00.00.00.00.00.05.00.00.00.00.0
Percentage of PaymentsOfDebtIssuanceCosts0.0100.00.00.00.00.00.00.00.00.0100.00.00.00.00.00.00.00.00.0100.00.00.00.00.0

us-gaap:ProceedsFromRepaymentsOfOtherDebt

us-gaap:ProceedsFromRepaymentsOfOtherDebt


Proceeds
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value2.4-3.31.1-1.6-297.9298-0.2-0.35.40.0-9.90.6-47.550-26.4-31.4-8.3670.7-0.1-149.7152-0.21.70.00.00.00.0-14.3-0.70.60.0-0.1-10.61.7-1.4-1.1-4.3-0.93.22.0-4.36.2-1.0
Percentage of ProceedsFromRepaymentsOfOtherDebt100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.00.00.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ProceedsFromSaleOfPropertyPlantAndEquipment

us-gaap:ProceedsFromSaleOfPropertyPlantAndEquipment


Proceeds
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-30
Value1.31.41.90.80.32.90.262290.01.40.4
Percentage of ProceedsFromSaleOfPropertyPlantAndEquipment100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0

us-gaap:ProvisionForDoubtfulAccounts

us-gaap:ProvisionForDoubtfulAccounts


Provision
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
Value200000.0100000.0-100000.0100000.0100000.0-100000.0100000.0100000.0100000.01200000.0100000.0300000.0300000.0
Percentage of ProvisionForDoubtfulAccounts100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax

us-gaap:ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax


Reclassification
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
Value-22.1-20.18.600000000000007-22.3-27.5-17.1-0.1-24.1-20.3-24.519-13.2-16.2-16.4-9.2-26.0-4.1-16.5-10.9-11.8-13.2-15.3-6.1-10.5-11.2-10.8-12.4-11.8-13.2-14.7-21.9-20.9-18.7-18.6
Percentage of ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax us-gaap:StatementEquityComponents

ati:AccumulatedDeferredTaxAssetValuationAllowance


Reclassification
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-31
Value-6.7-4.923-6.4-8.70.012-8.7-3.6-7.731-1.2-5.7-4.4-0.5-16.36.3-6.30.00.00.00.0
Percentage of ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax30.324.4277.928.731.6-0.0-12200.036.117.731.4164.89.135.226.85.462.7-153.738.2-0.0-0.0-0.0-0.0

us-gaap:AccumulatedDefinedBenefitPlansAdjustment


Reclassification
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
Value-16.5-16.5-15.6-15.6-15.6-15.7-15.8-16.1-16.3-16.1-13.6-14.0-14.0-14.3-11.0-10.5-11.2-10.8-11.3-11.4-11.4-12.2-12.4-12.5-12.5-12.5-13.5-13.4-13.5-13.4-15.2-18.3-18.3-18.2
Percentage of ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax74.782.1-181.470.056.791.815800.066.880.365.7-70.5106.186.487.2119.640.4273.265.5103.796.686.479.7203.3119.0111.6115.7108.9113.6102.391.269.487.697.997.8

us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedges


Reclassification
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
Value1.11.30.3-0.3-3.2-1.43.50.7-0.4-0.71.12.03.52.32.30.80.80.60.4-0.4-1.8-3.16.32.01.31.71.61.60.3-1.3-5.2-2.6-0.4-0.4
Percentage of ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax-5.0-6.53.51.311.68.2-3500.0-2.92.02.95.7-15.2-21.6-14.0-25.0-3.1-19.5-3.6-3.73.413.620.3-103.3-19.0-11.6-15.7-12.9-13.6-2.38.823.712.42.12.2

us-gaap:RepaymentsOfLongTermDebtAndCapitalSecurities

us-gaap:RepaymentsOfLongTermDebtAndCapitalSecurities


Repayments
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value4.13.02.62.32052.05022.01.81.51.81.81.51.33511.10.50.30.31.80.40.20.3176.00.30.2114030.10.1115.80.10.0105.80.0116155.85.20.06.00.15.2
Percentage of RepaymentsOfLongTermDebtAndCapitalSecurities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.00.0100.0100.0100.0100.00.0100.0100.0100.0

us-gaap:RestructuringAndRelatedCostNumberOfPositionsEliminated

us-gaap:RestructuringAndRelatedCostNumberOfPositionsEliminated


Restructuring
Period End2020-09-302020-06-302020-03-31
Value100.0550.090.0
Percentage of RestructuringAndRelatedCostNumberOfPositionsEliminated100.0100.0100.0

us-gaap:RestructuringCharges

us-gaap:RestructuringCharges


Restructuring
Period End2021-06-302020-09-302020-06-302020-03-312019-06-302016-12-31
Value-6.22.3168.00.021
Percentage of RestructuringCharges100.0100.0100.0100.00.0100.0

us-gaap:RestructuringCharges us-gaap:RestructuringCostAndReserve

ati:FacilityIdling


Restructuring
Period End2021-06-30
Value0.7
Percentage of RestructuringCharges-11.3

us-gaap:EmployeeSeverance


Restructuring
Period End2021-06-30
Value-6.9
Percentage of RestructuringCharges111.3

us-gaap:SeveranceCosts1

us-gaap:SeveranceCosts1


Severance
Period End2020-12-31
Value33
Percentage of SeveranceCosts1100.0

us-gaap:ValuationAllowanceDeferredTaxAssetChangeInAmount

us-gaap:ValuationAllowanceDeferredTaxAssetChangeInAmount


Valuation
Period End2020-12-312020-06-302019-12-312016-12-312016-09-302015-09-30
Value-26.099-41.922-173.1-63.9
Percentage of ValuationAllowanceDeferredTaxAssetChangeInAmount100.0100.0100.0100.0100.0100.0

us-gaap:WriteOffOfDeferredDebtIssuanceCost us-gaap:DebtInstrument, us-gaap:LongtermDebtType

us-gaap:WriteOffOfDeferredDebtIssuanceCost

ati:AlleghenyTechnologiesConvertibleSeniorNotes4.75Due2022, us-gaap:ConvertibleDebt


Write
Period End2020-12-31
Value0
Percentage of WriteOffOfDeferredDebtIssuanceCost0.0

ati:Accountsreceivablewithcustomers

ati:Accountsreceivablewithcustomers


Accountsreceivablewithcustomers
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
Value366428350392488597558601586570533594628611550
Percentage of Accountsreceivablewithcustomers100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

ati:AccumulatedOtherComprehensiveIncomeLossNetofTaxAttributabletoNoncontrollingInterest

ati:AccumulatedOtherComprehensiveIncomeLossNetofTaxAttributabletoNoncontrollingInterest


Accumulated
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-31
Value232121148.59.09.88.1121611122124171611119.714161719212524252524252726262423
Percentage of AccumulatedOtherComprehensiveIncomeLossNetofTaxAttributabletoNoncontrollingInterest100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

ati:AccumulatedOtherComprehensiveIncomeLossNetofTaxAttributabletoNoncontrollingInterest us-gaap:StatementEquityComponents

us-gaap:AccumulatedTranslationAdjustment


Accumulated
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-31
Value232121148.59.09.88.1121611122124171611119.714161719212524252524252726262423
Percentage of AccumulatedOtherComprehensiveIncomeLossNetofTaxAttributabletoNoncontrollingInterest100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

ati:DeferredTaxAssetsOtherComprehensiveIncomeLossDefinedBenefitPlans us-gaap:RetirementPlanType

ati:DeferredTaxAssetsOtherComprehensiveIncomeLossDefinedBenefitPlans

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit


Deferred
Period End2020-12-312019-12-312018-12-312017-12-312016-12-31
Value-38.1-34.4-35.3-29.7-28.2
Percentage of DeferredTaxAssetsOtherComprehensiveIncomeLossDefinedBenefitPlans100.0100.0100.0100.0100.0

us-gaap:PensionPlansDefinedBenefit


Deferred
Period End2020-12-312019-12-312018-12-312017-12-312016-12-31
Value-561.4-555.7-536.2-525.6-543.4
Percentage of DeferredTaxAssetsOtherComprehensiveIncomeLossDefinedBenefitPlans1473.51615.41519.01769.71927.0

ati:DeferredTaxLiabilitiesInventory

ati:DeferredTaxLiabilitiesInventory


Deferred
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-312009-12-31
Value5365675077621116677835747
Percentage of DeferredTaxLiabilitiesInventory100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

ati:DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetOfTaxEffect us-gaap:RetirementPlanType

ati:DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetOfTaxEffect

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit


Defined
Period End2020-12-312019-12-312018-12-312017-12-312016-12-31
Value-81.0-69.1-71.7-54.0-46.2
Percentage of DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetOfTaxEffect100.0100.0100.0100.0100.0

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2020-12-312019-12-312018-12-312017-12-312016-12-31
Value-1038.9-1014.0-934.1-900.5-919.3
Percentage of DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetOfTaxEffect1282.61467.41302.81667.61989.8

ati:DefinedBenefitPlanPercentOfEmployeesaccruingbenefitservice us-gaap:RetirementPlanSponsorLocation, us-gaap:RetirementPlanType

ati:DefinedBenefitPlanPercentOfEmployeesaccruingbenefitservice

country:US, us-gaap:PensionPlansDefinedBenefit


Defined
Period End2020-12-31
Value10.0
Percentage of DefinedBenefitPlanPercentOfEmployeesaccruingbenefitservice100.0

ati:DefinedBenefitPlanPlanAssetsPledgedAsCollateral us-gaap:RetirementPlanSponsorLocation

ati:DefinedBenefitPlanPlanAssetsPledgedAsCollateral

country:GB


Defined
Period End2020-12-31
Value62
Percentage of DefinedBenefitPlanPlanAssetsPledgedAsCollateral100.0

ati:DefinedContributionPlanDeferredContributionsDueToCOVID19Pandemic

ati:DefinedContributionPlanDeferredContributionsDueToCOVID19Pandemic


Defined
Period End2020-12-31
Value7300000.0
Percentage of DefinedContributionPlanDeferredContributionsDueToCOVID19Pandemic100.0

ati:Definedbenefitplannumberofemployeesaccruingbenefitservice us-gaap:RetirementPlanSponsorLocation, us-gaap:RetirementPlanType

ati:Definedbenefitplannumberofemployeesaccruingbenefitservice

country:US, us-gaap:PensionPlansDefinedBenefit


Definedbenefitplannumberofemployeesaccruingbenefitserviceus-gaap:
Period End2020-12-31
Value1300.0
Percentage of Definedbenefitplannumberofemployeesaccruingbenefitservice100.0

ati:EntityNumberOfEmployeesCoveredByUSWCollectiveBargainingAgreementsExpiringFebruary282021

ati:EntityNumberOfEmployeesCoveredByUSWCollectiveBargainingAgreementsExpiringFebruary282021


Entity
Period End2020-12-31
Value1100.0
Percentage of EntityNumberOfEmployeesCoveredByUSWCollectiveBargainingAgreementsExpiringFebruary282021100.0

ati:EntityWideDisclosureOnGeographicAreasTotalAssetsAttributedToIndividualCountriesPercentageAmount us-gaap:StatementGeographical

ati:EntityWideDisclosureOnGeographicAreasTotalAssetsAttributedToIndividualCountriesPercentageAmount

ati:OtherCountries


Entity
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-312009-12-31
Value6.00.040.040.050.030.020.020.020.030.030.020.02
Percentage of EntityWideDisclosureOnGeographicAreasTotalAssetsAttributedToIndividualCountriesPercentageAmount100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

country:CN


Entity
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-31
Value8.00.050.050.050.050.050.040.040.04
Percentage of EntityWideDisclosureOnGeographicAreasTotalAssetsAttributedToIndividualCountriesPercentageAmount133.3125.0125.0100.0166.7250.0200.0200.0133.3

country:GB


Entity
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-31
Value3.00.030.030.020.020.030.030.030.04
Percentage of EntityWideDisclosureOnGeographicAreasTotalAssetsAttributedToIndividualCountriesPercentageAmount50.075.075.040.066.7150.0150.0150.0133.3

country:US


Entity
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-31
Value83.00.880.880.880.890.880.90.890.88
Percentage of EntityWideDisclosureOnGeographicAreasTotalAssetsAttributedToIndividualCountriesPercentageAmount1383.32200.02200.01760.02966.74400.04500.04450.02933.3

ati:EnvironmentalRemediationObligationForFormerlyOwnedSites

ati:EnvironmentalRemediationObligationForFormerlyOwnedSites


Environmental
Period End2021-06-302021-03-312020-12-312020-09-30
Value8000000.08000000.09000000.09000000.0
Percentage of EnvironmentalRemediationObligationForFormerlyOwnedSites100.0100.0100.0100.0

ati:EnvironmentalRemediationObligationForOwnedOrControlledSitesWithClosedOperations

ati:EnvironmentalRemediationObligationForOwnedOrControlledSitesWithClosedOperations


Environmental
Period End2021-06-302021-03-312020-12-312020-09-30
Value2000000.01000000.01000000.01000000.0
Percentage of EnvironmentalRemediationObligationForOwnedOrControlledSitesWithClosedOperations100.0100.0100.0100.0

ati:FairValueInvestmentsUnfundedCommitments us-gaap:DefinedBenefitPlanByPlanAssetCategories, us-gaap:RetirementPlanType

ati:FairValueInvestmentsUnfundedCommitments

us-gaap:FixedIncomeFunds, us-gaap:PensionPlansDefinedBenefit


Fair
Period End2020-12-31
Value78
Percentage of FairValueInvestmentsUnfundedCommitments100.0

ati:GoodwillMeasurementInput us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:MeasurementInputType

ati:GoodwillMeasurementInput

us-gaap:FairValueInputsLevel3, ati:MeasurementInputWeightedAverageCostOfCapital


Goodwill
Period End2020-12-31
Value11.7
Percentage of GoodwillMeasurementInput100.0

ati:GoodwillMeasurementInput us-gaap:Range, us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:MeasurementInputType

srt:Maximum, us-gaap:FairValueInputsLevel3, us-gaap:MeasurementInputLongTermRevenueGrowthRate


Goodwill
Period End2020-12-31
Value3.5
Percentage of GoodwillMeasurementInput29.9

srt:Minimum, us-gaap:FairValueInputsLevel3, us-gaap:MeasurementInputLongTermRevenueGrowthRate


Goodwill
Period End2020-12-31
Value3.0
Percentage of GoodwillMeasurementInput25.6

ati:LesseeFinanceLeaseLeaseNotYetCommencedLiabilityToBeRecognized us-gaap:StatementScenario

ati:LesseeFinanceLeaseLeaseNotYetCommencedLiabilityToBeRecognized

srt:ScenarioForecast


Lessee
Period End2021-01-01
Value46
Percentage of LesseeFinanceLeaseLeaseNotYetCommencedLiabilityToBeRecognized100.0

ati:LesseeFinanceLeaseLeaseNotYetCommencedRightOfUseAssetToBeRecognized us-gaap:StatementScenario

ati:LesseeFinanceLeaseLeaseNotYetCommencedRightOfUseAssetToBeRecognized

srt:ScenarioForecast


Lessee
Period End2021-01-01
Value46
Percentage of LesseeFinanceLeaseLeaseNotYetCommencedRightOfUseAssetToBeRecognized100.0

ati:LineofCreditFacilityIncreasetoMaximumBorrowingCapacity us-gaap:StatementScenario, us-gaap:CreditFacility, us-gaap:DebtInstrument

ati:LineofCreditFacilityIncreasetoMaximumBorrowingCapacity

srt:ScenarioForecast, us-gaap:RevolvingCreditFacility, ati:DomesticBankGroup500millionassetbasedcreditfacility


Lineof
Period End2024-09-30
Value200
Percentage of LineofCreditFacilityIncreasetoMaximumBorrowingCapacity100.0

ati:LongLivedAssetMeasurementInput us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:MeasurementInputType, us-gaap:PropertyPlantAndEquipmentByType

ati:LongLivedAssetMeasurementInput

us-gaap:FairValueInputsLevel3, ati:MeasurementInputWeightedAverageCostOfCapital, ati:BrackenridgePAOperations


Long
Period End2020-12-31
Value9.3
Percentage of LongLivedAssetMeasurementInput100.0

us-gaap:FairValueInputsLevel3, us-gaap:MeasurementInputLongTermRevenueGrowthRate, ati:BrackenridgePAOperations


Long
Period End2020-12-31
Value2.0
Percentage of LongLivedAssetMeasurementInput21.5

ati:PercentageOfTotalAssetsUsQualifiedPlan us-gaap:RetirementPlanSponsorLocation, us-gaap:RetirementPlanType

ati:PercentageOfTotalAssetsUsQualifiedPlan

country:US, us-gaap:PensionPlansDefinedBenefit


Percentage
Period End2020-12-31
Value90.0
Percentage of PercentageOfTotalAssetsUsQualifiedPlan100.0

ati:ProgressPaymentsMadeOnBehalfOfCompanyPaid

ati:ProgressPaymentsMadeOnBehalfOfCompanyPaid


Progress
Period End2020-12-31
Value17
Percentage of ProgressPaymentsMadeOnBehalfOfCompanyPaid100.0

ati:ProgressPaymentsMadeOnBehalfOfCompanyScheduledToBePaid

ati:ProgressPaymentsMadeOnBehalfOfCompanyScheduledToBePaid


Progress
Period End2021-01-01
Value29
Percentage of ProgressPaymentsMadeOnBehalfOfCompanyScheduledToBePaid100.0

ati:RetainedEarningsEquityMethodUndistributedEarnings

ati:RetainedEarningsEquityMethodUndistributedEarnings


Retained
Period End2020-12-31
Value12
Percentage of RetainedEarningsEquityMethodUndistributedEarnings100.0

ati:RevenueRemainingPerformanceObligationCurrent

ati:RevenueRemainingPerformanceObligationCurrent


Revenue
Period End2021-06-302021-03-312020-12-312020-09-30
Value75.075.075.070.0
Percentage of RevenueRemainingPerformanceObligationCurrent100.0100.0100.0100.0

ati:SharebasedCompensationArrangementbySharebasedPaymentAwardExpectedCompensationCost us-gaap:Range, us-gaap:AwardType, us-gaap:PlanName

ati:SharebasedCompensationArrangementbySharebasedPaymentAwardExpectedCompensationCost

srt:Maximum, us-gaap:PerformanceShares, ati:PSU


Sharebased
Period End2020-12-312019-12-312018-12-31
Value5251-34.8
Percentage of SharebasedCompensationArrangementbySharebasedPaymentAwardExpectedCompensationCost100.0100.0100.0

ati:TotalDebt

ati:TotalDebt


Total
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
Value16211614156715411529170013981553154815421542155115511599154019141944194518771875187616491495150515211527152615261538194619471962147314791480147915011509150916281650156110631071
Percentage of TotalDebt100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

ati:UnrecognizedTaxBenefitsReductionofOperatingLossCarryforwards

ati:UnrecognizedTaxBenefitsReductionofOperatingLossCarryforwards


Unrecognized
Period End2020-12-312019-12-312018-12-312017-12-31
Value13111211
Percentage of UnrecognizedTaxBenefitsReductionofOperatingLossCarryforwards100.0100.0100.0100.0

dei:EntityNumberOfEmployees

dei:EntityNumberOfEmployees


Entity
Period End2020-12-312018-12-312017-12-312016-12-312015-12-312014-12-31
Value6500.08800.08600.08500.09200.09700.0
Percentage of EntityNumberOfEmployees100.0100.0100.0100.0100.0100.0

us-gaap:AccountsReceivableRelatedPartiesCurrent us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName

us-gaap:AccountsReceivableRelatedPartiesCurrent

ati:Uniti


Accounts
Period End2020-12-312019-12-312018-12-312017-12-31
Value1.40.21.81.2
Percentage of AccountsReceivableRelatedPartiesCurrent100.0100.0100.0100.0

us-gaap:AccrualForEnvironmentalLossContingencies

us-gaap:AccrualForEnvironmentalLossContingencies


Accrual
Period End2021-06-302021-03-312020-12-312020-09-302018-12-312017-12-31
Value131314142012
Percentage of AccrualForEnvironmentalLossContingencies100.0100.0100.0100.0100.0100.0

us-gaap:AllowanceForDoubtfulAccountsReceivable

us-gaap:AllowanceForDoubtfulAccountsReceivable


Allowance
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value3900000.04200000.04300000.04300000.04500000.04400000.04600000.05000000.05000000.05700000.06000000.06200000.06100000.05900000.05900000.07300000.04500000.04700000.04800000.04800000.04800000.04800000.04900000.05100000.05300000.05200000.05800000.05300000.05500000.05600000.05600000.05300000.05900000.06800000.07300000.05600000.05600000.06500000.0
Percentage of AllowanceForDoubtfulAccountsReceivable100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:AssetRetirementObligation

us-gaap:AssetRetirementObligation


Asset
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-312009-12-312008-12-31
Value24232323232525271312131411
Percentage of AssetRetirementObligation100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:BuildingsAndImprovementsGross

us-gaap:BuildingsAndImprovementsGross


Buildings
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
Value57456956488487686183282181785385185184984984484284083082984710701061104810481051105310481035103210221019947970934921870830790757719705667638590
Percentage of BuildingsAndImprovementsGross100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:CapitalizedContractCostNet

us-gaap:CapitalizedContractCostNet


Capitalized
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value5500000.05300000.05400000.05600000.06100000.06300000.06500000.05100000.05400000.05200000.05200000.0
Percentage of CapitalizedContractCostNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:CashAndCashEquivalentsFairValueDisclosure us-gaap:FairValueByFairValueHierarchyLevel

us-gaap:CashAndCashEquivalentsFairValueDisclosure

us-gaap:FairValueInputsLevel1


Cash
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-31
Value6454903821412291492691026
Percentage of CashAndCashEquivalentsFairValueDisclosure100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:CashAndCashEquivalentsFairValueDisclosure us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementBasis

us-gaap:FairValueInputsLevel1, us-gaap:EstimateOfFairValueFairValueDisclosure


Cash
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-31
Value472541645572539639490511281217382153122109141124154159229188322156149197250238269
Percentage of CashAndCashEquivalentsFairValueDisclosure0.00.0100.00.00.00.0100.00.00.00.0100.00.00.00.0100.00.00.00.0100.00.00.00.0100.00.00.00.0100.0

us-gaap:CashAndCashEquivalentsFairValueDisclosure us-gaap:FairValueByMeasurementBasis

us-gaap:CarryingReportedAmountFairValueDisclosure


Cash
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-31
Value4725416455725396394905112812173821531221091411241541592291883221561491972502382692643558371026
Percentage of CashAndCashEquivalentsFairValueDisclosure0.00.0100.00.00.00.0100.00.00.00.0100.00.00.00.0100.00.00.00.0100.00.00.00.0100.00.00.00.0100.00.00.00.0100.0

us-gaap:EstimateOfFairValueFairValueDisclosure


Cash
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-31
Value4725416455725396394905112812173821531221091411241541592291883221561491972502382692643558371026
Percentage of CashAndCashEquivalentsFairValueDisclosure0.00.0100.00.00.00.0100.00.00.00.0100.00.00.00.0100.00.00.00.0100.00.00.00.0100.00.00.00.0100.00.00.00.0100.0

us-gaap:ContractWithCustomerAssetNetCurrent

us-gaap:ContractWithCustomerAssetNetCurrent


Contract
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
Value52423841414338374048515147380.0
Percentage of ContractWithCustomerAssetNetCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0

us-gaap:ContractWithCustomerLiabilityNoncurrent

us-gaap:ContractWithCustomerLiabilityNoncurrent


Contract
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
Value705532313229257.37.37.37.37.314190.0
Percentage of ContractWithCustomerLiabilityNoncurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0

us-gaap:DebtInstrumentCarryingAmount us-gaap:DebtInstrument

us-gaap:DebtInstrumentCarryingAmount

ati:A2024TermLoan