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element represents realized gains (losses) included in earnings during the period in relation to assets and liabilities measured at fair value on a recurring basis using unobservable inputs (Level 3).No definition available.false2Realized Gains Losses Due To Ineffectiveness3false 3etr_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetAndLiabilitiesValueetr_falsedebitinstantfalsefalsefalsefalsefalsetruefalsefalseperiodStartLabel1truefalsefalse5200000052falsefalsefalse2truefalsefalse528000000528falsefalsefalse3truefalsefalse178000000178falsefalsefalse4truefalsefalse312000000312falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents an asset and liabilities measured at fair value using significant unobservable inputs (Level 3) which is required for reconciliation purposes of beginning and ending balances.No definition available.false2Balance as of Beginning of Period4false 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settlements (net) which have taken place during the period in relation to assets and liabilities measured at fair value on a recurring basis using unobservable inputs (Level 3).No definition available.false2Realized gains on settlements7false 3etr_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetAndLiabilitiesValueetr_falsedebitinstantfalsefalsefalsefalsefalsefalsetruefalseperiodEndLabel1truefalsefalse8300000083USD$falsetruefalse2truefalsefalse375000000375USD$falsetruefalse3truefalsefalse8300000083USD$falsetruefalse4truefalsefalse375000000375USD$falsetruefalsexbrli:monetaryItemTypemonetaryThis element represents an asset and liabilities measured at fair value using significant unobservable inputs (Level 3) which is required for reconciliation purposes of beginning and ending balances.No definition available.false2Balance as of End of PeriodfalseRisk Management and Fair Values (Reconciliation Of Changes In The Net Assets (Liabilities) For The Fair Value Of 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