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Derivative Financial Instruments and Hedging (Details) In Millions, unless otherwise specified | 3 Months Ended |  | 3 Months Ended |  | 3 Months Ended
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Mar. 31, 2015 USD ($) | Mar. 31, 2015 Other Comprehensive Income Cash Flow Hedging USD ($) | Mar. 31, 2014 Other Comprehensive Income Cash Flow Hedging USD ($) | Mar. 31, 2015 Cost Of Sales Cash Flow Hedging USD ($) | Mar. 31, 2014 Cost Of Sales Cash Flow Hedging USD ($) | Mar. 31, 2015 Selling And Administrative Expenses Cash Flow Hedging USD ($) | Mar. 31, 2014 Selling And Administrative Expenses Cash Flow Hedging USD ($) | Mar. 31, 2015 Nickel and other raw material contracts Other Comprehensive Income Cash Flow Hedging USD ($) | Mar. 31, 2014 Nickel and other raw material contracts Other Comprehensive Income Cash Flow Hedging USD ($) | Mar. 31, 2015 Nickel and other raw material contracts Cost Of Sales Cash Flow Hedging USD ($) | Mar. 31, 2014 Nickel and other raw material contracts Cost Of Sales Cash Flow Hedging USD ($) | Mar. 31, 2015 Nickel and other raw material contracts Selling And Administrative Expenses Cash Flow Hedging USD ($) | Mar. 31, 2014 Nickel and other raw material contracts Selling And Administrative Expenses Cash Flow Hedging USD ($) | Mar. 31, 2015 Natural gas contracts Other Comprehensive Income Cash Flow Hedging USD ($) | Mar. 31, 2014 Natural gas contracts Other Comprehensive Income Cash Flow Hedging USD ($) | Mar. 31, 2015 Natural gas contracts Cost Of Sales Cash Flow Hedging USD ($) | Mar. 31, 2014 Natural gas contracts Cost Of Sales Cash Flow Hedging USD ($) | Mar. 31, 2015 Natural gas contracts Selling And Administrative Expenses Cash Flow Hedging USD ($) | Mar. 31, 2014 Natural gas contracts Selling And Administrative Expenses Cash Flow Hedging USD ($) | Mar. 31, 2015 Electricity contracts Other Comprehensive Income Cash Flow Hedging USD ($) | Mar. 31, 2014 Electricity contracts Other Comprehensive Income Cash Flow Hedging USD ($) | Mar. 31, 2015 Electricity contracts Cost Of Sales Cash Flow Hedging USD ($) | Mar. 31, 2014 Electricity contracts Cost Of Sales Cash Flow Hedging USD ($) | Mar. 31, 2015 Electricity contracts Selling And Administrative Expenses Cash Flow Hedging USD ($) | Mar. 31, 2014 Electricity contracts Selling And Administrative Expenses Cash Flow Hedging USD ($) | Mar. 31, 2015 Foreign exchange contracts Other Comprehensive Income Cash Flow Hedging USD ($) | Mar. 31, 2014 Foreign exchange contracts Other Comprehensive Income Cash Flow Hedging USD ($) | Mar. 31, 2015 Foreign exchange contracts Cost Of Sales Cash Flow Hedging USD ($) | Mar. 31, 2014 Foreign exchange contracts Cost Of Sales Cash Flow Hedging USD ($) | Mar. 31, 2015 Foreign exchange contracts Selling And Administrative Expenses Cash Flow Hedging USD ($) | Mar. 31, 2014 Foreign exchange contracts Selling And Administrative Expenses Cash Flow Hedging USD ($) | Mar. 31, 2015 Designated as Hedging Instrument Foreign exchange forward Cash Flow Hedging USD ($) | Mar. 31, 2015 Designated as Hedging Instrument Foreign exchange forward Cash Flow Hedging EUR (€) | Mar. 31, 2015 Designated as Hedging Instrument Foreign exchange forward Cost Of Sales Fair Value Hedging USD ($) | Mar. 31, 2015 Designated as Hedging Instrument Foreign exchange forward Maturity dates Through February 2018 EUR (€) | Mar. 31, 2015 Designated as Hedging Instrument Foreign exchange forward Maturity Dates Through 2015 EUR (€) | Mar. 31, 2015 Designated as Hedging Instrument Foreign exchange forward Maturity Dates Through 2015 Fair Value Hedging EUR (€) | Mar. 31, 2015 Not Designated as Hedging Instrument Foreign exchange forward USD ($) | Mar. 31, 2015 Not Designated as Hedging Instrument Foreign exchange forward EUR (€) | Mar. 31, 2015 Not Designated as Hedging Instrument Foreign exchange forward Maturity Dates Through February 2016 EUR (€) | Mar. 31, 2015 Not Designated as Hedging Instrument Foreign exchange contracts Cost Of Sales USD ($) | Mar. 31, 2014 Not Designated as Hedging Instrument Foreign exchange contracts Cost Of Sales USD ($)
Notional Disclosures [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Percentage of estimated annual nickel requirements | 20.00%ati_PercentageOfRawMaterialUsageHedged |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Percentage of forecasted natural gas usage hedged for 2015 | 80.00%ati_PercentageOfForecastedNaturalGasUsageHedgedforYear1 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Percentage Of Forecasted Natural Gas Usage Hedged for 2016 | 75.00%ati_PercentageOfForecastedNaturalGasUsageHedgedforYear2 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Percentage Of Forecasted Natural Gas Usage Hedged for 2017 | 45.00%ati_PercentageOfForecastedNaturalGasUsageHedgedforYear3 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Derivative Instruments Gain Loss [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Notional amount of derivative |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | € 375 invest_DerivativeNotionalAmount / us-gaap_DerivativeInstrumentRiskAxis = us-gaap_ForeignExchangeForwardMember / ati_DerivativeMaturityRangeAxis = ati_MaturityDatesThrough2018Member / us-gaap_HedgingDesignationAxis = us-gaap_DesignatedAsHedgingInstrumentMember | € 157 invest_DerivativeNotionalAmount / us-gaap_DerivativeInstrumentRiskAxis = us-gaap_ForeignExchangeForwardMember / ati_DerivativeMaturityRangeAxis = ati_MaturityDatesThrough2015Member / us-gaap_HedgingDesignationAxis = us-gaap_DesignatedAsHedgingInstrumentMember | € 115 invest_DerivativeNotionalAmount / us-gaap_DerivativeInstrumentRiskAxis = us-gaap_ForeignExchangeForwardMember / us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis = us-gaap_FairValueHedgingMember / ati_DerivativeMaturityRangeAxis = ati_MaturityDatesThrough2015Member / us-gaap_HedgingDesignationAxis = us-gaap_DesignatedAsHedgingInstrumentMember |  |  | € 30 invest_DerivativeNotionalAmount / us-gaap_DerivativeInstrumentRiskAxis = us-gaap_ForeignExchangeForwardMember / ati_DerivativeMaturityRangeAxis = ati_MaturityDatesThrough2016Member / us-gaap_HedgingDesignationAxis = us-gaap_NondesignatedMember |  |
Derivative Instruments Gain Loss Recognized In Other Comprehensive Income Effective Portion Net |  | 11.4 us-gaap_DerivativeInstrumentsGainLossRecognizedInOtherComprehensiveIncomeEffectivePortionNet / us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis = us-gaap_CashFlowHedgingMember / us-gaap_IncomeStatementLocationAxis = us-gaap_OtherComprehensiveIncomeMember | 5.7 us-gaap_DerivativeInstrumentsGainLossRecognizedInOtherComprehensiveIncomeEffectivePortionNet / us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis = us-gaap_CashFlowHedgingMember / us-gaap_IncomeStatementLocationAxis = us-gaap_OtherComprehensiveIncomeMember |  |  |  |  | (9.6)us-gaap_DerivativeInstrumentsGainLossRecognizedInOtherComprehensiveIncomeEffectivePortionNet / us-gaap_DerivativeInstrumentRiskAxis = ati_NickelAndOtherRawMaterialContractsMember / us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis = us-gaap_CashFlowHedgingMember / us-gaap_IncomeStatementLocationAxis = us-gaap_OtherComprehensiveIncomeMember | 3.0 us-gaap_DerivativeInstrumentsGainLossRecognizedInOtherComprehensiveIncomeEffectivePortionNet / us-gaap_DerivativeInstrumentRiskAxis = ati_NickelAndOtherRawMaterialContractsMember / us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis = us-gaap_CashFlowHedgingMember / us-gaap_IncomeStatementLocationAxis = us-gaap_OtherComprehensiveIncomeMember |  |  |  |  | (6.0)us-gaap_DerivativeInstrumentsGainLossRecognizedInOtherComprehensiveIncomeEffectivePortionNet / us-gaap_DerivativeInstrumentRiskAxis = ati_NaturalGasContractsMember / us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis = us-gaap_CashFlowHedgingMember / us-gaap_IncomeStatementLocationAxis = us-gaap_OtherComprehensiveIncomeMember | 2.3 us-gaap_DerivativeInstrumentsGainLossRecognizedInOtherComprehensiveIncomeEffectivePortionNet / us-gaap_DerivativeInstrumentRiskAxis = ati_NaturalGasContractsMember / us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis = us-gaap_CashFlowHedgingMember / us-gaap_IncomeStatementLocationAxis = us-gaap_OtherComprehensiveIncomeMember |  |  |  |  | 0 us-gaap_DerivativeInstrumentsGainLossRecognizedInOtherComprehensiveIncomeEffectivePortionNet / us-gaap_DerivativeInstrumentRiskAxis = ati_ElectricityContractsMember / us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis = us-gaap_CashFlowHedgingMember / us-gaap_IncomeStatementLocationAxis = us-gaap_OtherComprehensiveIncomeMember | 0.9 us-gaap_DerivativeInstrumentsGainLossRecognizedInOtherComprehensiveIncomeEffectivePortionNet / us-gaap_DerivativeInstrumentRiskAxis = ati_ElectricityContractsMember / us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis = us-gaap_CashFlowHedgingMember / us-gaap_IncomeStatementLocationAxis = us-gaap_OtherComprehensiveIncomeMember |  |  |  |  | 27.0 us-gaap_DerivativeInstrumentsGainLossRecognizedInOtherComprehensiveIncomeEffectivePortionNet / us-gaap_DerivativeInstrumentRiskAxis = us-gaap_ForeignExchangeContractMember / us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis = us-gaap_CashFlowHedgingMember / us-gaap_IncomeStatementLocationAxis = us-gaap_OtherComprehensiveIncomeMember | (0.5)us-gaap_DerivativeInstrumentsGainLossRecognizedInOtherComprehensiveIncomeEffectivePortionNet / us-gaap_DerivativeInstrumentRiskAxis = us-gaap_ForeignExchangeContractMember / us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis = us-gaap_CashFlowHedgingMember / us-gaap_IncomeStatementLocationAxis = us-gaap_OtherComprehensiveIncomeMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Derivative Instruments Gain Loss Reclassified From Accumulated OCI Into Income Effective Portion Net |  |  |  | 1.7 us-gaap_DerivativeInstrumentsGainLossReclassifiedFromAccumulatedOCIIntoIncomeEffectivePortionNet / us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis = us-gaap_CashFlowHedgingMember / us-gaap_IncomeStatementLocationAxis = us-gaap_CostOfSalesMember | (1.3)us-gaap_DerivativeInstrumentsGainLossReclassifiedFromAccumulatedOCIIntoIncomeEffectivePortionNet / us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis = us-gaap_CashFlowHedgingMember / us-gaap_IncomeStatementLocationAxis = us-gaap_CostOfSalesMember |  |  |  |  | (2.2)us-gaap_DerivativeInstrumentsGainLossReclassifiedFromAccumulatedOCIIntoIncomeEffectivePortionNet / us-gaap_DerivativeInstrumentRiskAxis = ati_NickelAndOtherRawMaterialContractsMember / us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis = us-gaap_CashFlowHedgingMember / us-gaap_IncomeStatementLocationAxis = us-gaap_CostOfSalesMember | (1.7)us-gaap_DerivativeInstrumentsGainLossReclassifiedFromAccumulatedOCIIntoIncomeEffectivePortionNet / us-gaap_DerivativeInstrumentRiskAxis = ati_NickelAndOtherRawMaterialContractsMember / us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis = us-gaap_CashFlowHedgingMember / us-gaap_IncomeStatementLocationAxis = us-gaap_CostOfSalesMember |  |  |  |  | (2.4)us-gaap_DerivativeInstrumentsGainLossReclassifiedFromAccumulatedOCIIntoIncomeEffectivePortionNet / us-gaap_DerivativeInstrumentRiskAxis = ati_NaturalGasContractsMember / us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis = us-gaap_CashFlowHedgingMember / us-gaap_IncomeStatementLocationAxis = us-gaap_CostOfSalesMember | 1.4 us-gaap_DerivativeInstrumentsGainLossReclassifiedFromAccumulatedOCIIntoIncomeEffectivePortionNet / us-gaap_DerivativeInstrumentRiskAxis = ati_NaturalGasContractsMember / us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis = us-gaap_CashFlowHedgingMember / us-gaap_IncomeStatementLocationAxis = us-gaap_CostOfSalesMember |  |  |  |  | (0.1)us-gaap_DerivativeInstrumentsGainLossReclassifiedFromAccumulatedOCIIntoIncomeEffectivePortionNet / us-gaap_DerivativeInstrumentRiskAxis = ati_ElectricityContractsMember / us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis = us-gaap_CashFlowHedgingMember / us-gaap_IncomeStatementLocationAxis = us-gaap_CostOfSalesMember | 0.4 us-gaap_DerivativeInstrumentsGainLossReclassifiedFromAccumulatedOCIIntoIncomeEffectivePortionNet / us-gaap_DerivativeInstrumentRiskAxis = ati_ElectricityContractsMember / us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis = us-gaap_CashFlowHedgingMember / us-gaap_IncomeStatementLocationAxis = us-gaap_CostOfSalesMember |  |  |  |  | 6.4 us-gaap_DerivativeInstrumentsGainLossReclassifiedFromAccumulatedOCIIntoIncomeEffectivePortionNet / us-gaap_DerivativeInstrumentRiskAxis = us-gaap_ForeignExchangeContractMember / us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis = us-gaap_CashFlowHedgingMember / us-gaap_IncomeStatementLocationAxis = us-gaap_CostOfSalesMember | (1.4)us-gaap_DerivativeInstrumentsGainLossReclassifiedFromAccumulatedOCIIntoIncomeEffectivePortionNet / us-gaap_DerivativeInstrumentRiskAxis = us-gaap_ForeignExchangeContractMember / us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis = us-gaap_CashFlowHedgingMember / us-gaap_IncomeStatementLocationAxis = us-gaap_CostOfSalesMember |  |  |  |  |  |  |  |  |  |  |  |  |
Derivative Instruments Gain Loss Recognized In Income Ineffective Portion And Amount Excluded From Effectiveness Testing Net |  |  |  |  |  | 0 us-gaap_DerivativeInstrumentsGainLossRecognizedInIncomeIneffectivePortionAndAmountExcludedFromEffectivenessTestingNet / us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis = us-gaap_CashFlowHedgingMember / us-gaap_IncomeStatementLocationAxis = ati_SellingAndAdministrativeExpensesMember | 0 us-gaap_DerivativeInstrumentsGainLossRecognizedInIncomeIneffectivePortionAndAmountExcludedFromEffectivenessTestingNet / us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis = us-gaap_CashFlowHedgingMember / us-gaap_IncomeStatementLocationAxis = ati_SellingAndAdministrativeExpensesMember |  |  |  |  | 0 us-gaap_DerivativeInstrumentsGainLossRecognizedInIncomeIneffectivePortionAndAmountExcludedFromEffectivenessTestingNet / us-gaap_DerivativeInstrumentRiskAxis = ati_NickelAndOtherRawMaterialContractsMember / us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis = us-gaap_CashFlowHedgingMember / us-gaap_IncomeStatementLocationAxis = ati_SellingAndAdministrativeExpensesMember | 0 us-gaap_DerivativeInstrumentsGainLossRecognizedInIncomeIneffectivePortionAndAmountExcludedFromEffectivenessTestingNet / us-gaap_DerivativeInstrumentRiskAxis = ati_NickelAndOtherRawMaterialContractsMember / us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis = us-gaap_CashFlowHedgingMember / us-gaap_IncomeStatementLocationAxis = ati_SellingAndAdministrativeExpensesMember |  |  |  |  | 0 us-gaap_DerivativeInstrumentsGainLossRecognizedInIncomeIneffectivePortionAndAmountExcludedFromEffectivenessTestingNet / us-gaap_DerivativeInstrumentRiskAxis = ati_NaturalGasContractsMember / us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis = us-gaap_CashFlowHedgingMember / us-gaap_IncomeStatementLocationAxis = ati_SellingAndAdministrativeExpensesMember | 0 us-gaap_DerivativeInstrumentsGainLossRecognizedInIncomeIneffectivePortionAndAmountExcludedFromEffectivenessTestingNet / us-gaap_DerivativeInstrumentRiskAxis = ati_NaturalGasContractsMember / us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis = us-gaap_CashFlowHedgingMember / us-gaap_IncomeStatementLocationAxis = ati_SellingAndAdministrativeExpensesMember |  |  |  |  | 0 us-gaap_DerivativeInstrumentsGainLossRecognizedInIncomeIneffectivePortionAndAmountExcludedFromEffectivenessTestingNet / us-gaap_DerivativeInstrumentRiskAxis = ati_ElectricityContractsMember / us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis = us-gaap_CashFlowHedgingMember / us-gaap_IncomeStatementLocationAxis = ati_SellingAndAdministrativeExpensesMember | 0 us-gaap_DerivativeInstrumentsGainLossRecognizedInIncomeIneffectivePortionAndAmountExcludedFromEffectivenessTestingNet / us-gaap_DerivativeInstrumentRiskAxis = ati_ElectricityContractsMember / us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis = us-gaap_CashFlowHedgingMember / us-gaap_IncomeStatementLocationAxis = ati_SellingAndAdministrativeExpensesMember |  |  |  |  | 0 us-gaap_DerivativeInstrumentsGainLossRecognizedInIncomeIneffectivePortionAndAmountExcludedFromEffectivenessTestingNet / us-gaap_DerivativeInstrumentRiskAxis = us-gaap_ForeignExchangeContractMember / us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis = us-gaap_CashFlowHedgingMember / us-gaap_IncomeStatementLocationAxis = ati_SellingAndAdministrativeExpensesMember | 0 us-gaap_DerivativeInstrumentsGainLossRecognizedInIncomeIneffectivePortionAndAmountExcludedFromEffectivenessTestingNet / us-gaap_DerivativeInstrumentRiskAxis = us-gaap_ForeignExchangeContractMember / us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis = us-gaap_CashFlowHedgingMember / us-gaap_IncomeStatementLocationAxis = ati_SellingAndAdministrativeExpensesMember |  |  |  |  |  |  |  |  |  |  |
Derivative Instruments Gain Loss Recognized In Income Net |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 3.5 us-gaap_DerivativeGainLossOnDerivativeNet / us-gaap_DerivativeInstrumentRiskAxis = us-gaap_ForeignExchangeContractMember / us-gaap_HedgingDesignationAxis = us-gaap_NondesignatedMember / us-gaap_IncomeStatementLocationAxis = us-gaap_CostOfSalesMember | 0.2 us-gaap_DerivativeGainLossOnDerivativeNet / us-gaap_DerivativeInstrumentRiskAxis = us-gaap_ForeignExchangeContractMember / us-gaap_HedgingDesignationAxis = us-gaap_NondesignatedMember / us-gaap_IncomeStatementLocationAxis = us-gaap_CostOfSalesMember
Notional amount of derivatives net settled |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 126.5 ati_DerivativeNotionalAmountNetSettled / us-gaap_DerivativeInstrumentRiskAxis = us-gaap_ForeignExchangeForwardMember / us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis = us-gaap_CashFlowHedgingMember / us-gaap_HedgingDesignationAxis = us-gaap_DesignatedAsHedgingInstrumentMember |  |  |  |  |  | 40.3 ati_DerivativeNotionalAmountNetSettled / us-gaap_DerivativeInstrumentRiskAxis = us-gaap_ForeignExchangeForwardMember / us-gaap_HedgingDesignationAxis = us-gaap_NondesignatedMember |  |  |
Cash proceeds from settlement of hedge |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 26.1 us-gaap_DerivativeCashReceivedOnHedge / us-gaap_DerivativeInstrumentRiskAxis = us-gaap_ForeignExchangeForwardMember / us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis = us-gaap_CashFlowHedgingMember / us-gaap_HedgingDesignationAxis = us-gaap_DesignatedAsHedgingInstrumentMember |  |  |  |  |  | 11.8 us-gaap_DerivativeCashReceivedOnHedge / us-gaap_DerivativeInstrumentRiskAxis = us-gaap_ForeignExchangeForwardMember / us-gaap_HedgingDesignationAxis = us-gaap_NondesignatedMember |  |  |  |
Gain on derivative |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 5.0 us-gaap_DerivativeGainOnDerivative / us-gaap_DerivativeInstrumentRiskAxis = us-gaap_ForeignExchangeForwardMember / us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis = us-gaap_FairValueHedgingMember / us-gaap_HedgingDesignationAxis = us-gaap_DesignatedAsHedgingInstrumentMember / us-gaap_IncomeStatementLocationAxis = us-gaap_CostOfSalesMember |  |  |  |  |  |  |  |
Reclassification of Cash Flow Hedge Gain (Loss) [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Cash Flow Hedge Gain Loss To Be Reclassified Within Twelve Months | $ 0.7 us-gaap_CashFlowHedgeGainLossToBeReclassifiedWithinTwelveMonths |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |

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- Definition Aggregate notional amount of price risk derivatives for instruments with notional amounts expressed in percentage of estimated annual domestic (U.S.) usage + References No definition available. + Details
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- Definition Aggregate notional amount of price risk derivatives for instruments with notional amounts expressed in percentage of estimated annual domestic (U.S.) usage + References No definition available. + Details
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- Definition Aggregate notional amount of price risk derivatives for instruments with notional amounts expressed in percentage of estimated annual domestic (U.S.) usage + References No definition available. + Details
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- Definition Aggregate notional amount specified by the derivative(s). Expressed as an absolute value. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Article 12 -Section 13 -Sentence Column B + Details
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- Definition The estimated net amount of existing gains or losses on cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=35736893&loc=d3e80748-113994 + Details
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- Definition The amount of cash received during the period on settlement of a hedge. + References No definition available. + Details
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- Definition Amount of increase in the fair value of derivatives recognized in the income statement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4A -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5618551-113959 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -Subparagraph (a),(c),(d),(e) -URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5624171-113959 + Details
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- Definition The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5624171-113959 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4D -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5624177-113959 + Details
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- Definition The portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments representing (a) the amount of the hedge ineffectiveness and (b) the amount, if any, excluded from the assessment of hedge effectiveness. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5624171-113959 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 25 -Section 50 -Paragraph 1 -Subparagraph (a)(1),(2) -URI http://asc.fasb.org/extlink&oid=6886632&loc=d3e76258-113986 + Details
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- Definition The effective portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments that was recognized in other comprehensive income during the current period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5624171-113959 + Details
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