XML 40 R87.htm IDEA: XBRL DOCUMENT v2.4.1.9
Pensions, Other Post-employment Benefits and Employee Benefit Plans Benefit Obligations and Plan Assets (Details) (USD $)
12 Months Ended
Dec. 31, 2014
Dec. 31, 2013
Dec. 31, 2012
Automotive Segment [Member]      
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]      
Defined Benefit Plan, Effect of One Percentage Point Increase on Service and Interest Cost Components $ 1,000,000us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointIncreaseOnServiceAndInterestCostComponents
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= iep_AutomotiveSegmentMember
   
Defined Benefit Plan, Health Care Cost Trend Rate Assumed for Next Fiscal Year 7.25%us-gaap_DefinedBenefitPlanHealthCareCostTrendRateAssumedForNextFiscalYear
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= iep_AutomotiveSegmentMember
6.88%us-gaap_DefinedBenefitPlanHealthCareCostTrendRateAssumedForNextFiscalYear
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= iep_AutomotiveSegmentMember
 
Defined Benefit Plan, Ultimate Health Care Cost Trend Rate 5.00%us-gaap_DefinedBenefitPlanUltimateHealthCareCostTrendRate
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= iep_AutomotiveSegmentMember
5.00%us-gaap_DefinedBenefitPlanUltimateHealthCareCostTrendRate
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= iep_AutomotiveSegmentMember
 
Defined Benefit Plan, Year that Rate Reaches Ultimate Trend Rate 2022 2018  
Defined benefit plan, drug cost trend rate 7.25%iep_DefinedBenefitPlanDrugCostTrendRate
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= iep_AutomotiveSegmentMember
7.81%iep_DefinedBenefitPlanDrugCostTrendRate
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= iep_AutomotiveSegmentMember
 
Defined benefit plan, ultimate drug cost trend rate 5.00%iep_DefinedBenefitPlanUltimateDrugCostTrendRate
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= iep_AutomotiveSegmentMember
5.00%iep_DefinedBenefitPlanUltimateDrugCostTrendRate
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= iep_AutomotiveSegmentMember
 
Defined Benefit Plan Year That Drug Cost Rate Reaches Ultimate Trend Rate 2022 2018  
Defined Benefit Plan, Effect of One Percentage Point Increase on Accumulated Postretirement Benefit Obligation 32,000,000us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointIncreaseOnAccumulatedPostretirementBenefitObligation
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Defined Benefit Plan, Effect of One Percentage Point Decrease on Service and Interest Cost Components (1,000,000)us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointDecreaseOnServiceAndInterestCostComponents1
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Defined Benefit Plan, Effect of One Percentage Point Decrease on Accumulated Postretirement Benefit Obligation (28,000,000)us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointDecreaseOnAccumulatedPostretirementBenefitObligation1
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
   
United States Plans | Automotive Segment [Member]      
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]      
Defined Benefit Plan, Expected Future Benefit Payments, Next Twelve Months 94,000,000us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsNextTwelveMonths
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Defined benefit plans, amount in AOCI expected to be reclassed into net periodic benefit cost in the next year, amortization of actuarial losses   0iep_DefinedBenefitPlansAmountInAociExpectedToBeReclassedIntoNetPeriodicBenefitCostInNextYearAmortizationOfActuarialLosses
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Defined Benefit Plan, Pension Plans with Accumulated Benefit Obligations in Excess of Plan Assets, Aggregate Projected Benefit Obligation 0us-gaap_DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateProjectedBenefitObligation
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0us-gaap_DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateProjectedBenefitObligation
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Defined benefit plan, plans with projected benefit obligations in excess of plan assets, aggregate projected benefit obligation 0iep_DefinedBenefitPlanPlansWithProjectedBenefitObligationsInExcessOfPlanAssetsAggregateProjectedBenefitObligation
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0iep_DefinedBenefitPlanPlansWithProjectedBenefitObligationsInExcessOfPlanAssetsAggregateProjectedBenefitObligation
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Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Discount Rate 4.55%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostDiscountRate
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3.70%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostDiscountRate
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= us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember
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= iep_AutomotiveSegmentMember
 
Defined benefit plan, assumption used calculated projected benefit obligation, discount rate 3.85%iep_DefinedBenefitPlanAssumptionUsedCalculatedProjectedBenefitObligationDiscountRate
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4.55%iep_DefinedBenefitPlanAssumptionUsedCalculatedProjectedBenefitObligationDiscountRate
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= us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember
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Defined Benefit Plan, Benefit Obligation 1,291,000,000us-gaap_DefinedBenefitPlanBenefitObligation
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1,184,000,000us-gaap_DefinedBenefitPlanBenefitObligation
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1,298,000,000us-gaap_DefinedBenefitPlanBenefitObligation
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Service cost 3,000,000us-gaap_DefinedBenefitPlanServiceCost
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4,000,000us-gaap_DefinedBenefitPlanServiceCost
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Interest cost 52,000,000us-gaap_DefinedBenefitPlanInterestCost
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47,000,000us-gaap_DefinedBenefitPlanInterestCost
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Employee contributions 0us-gaap_DefinedBenefitPlanContributionsByPlanParticipants
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0us-gaap_DefinedBenefitPlanContributionsByPlanParticipants
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Benefits paid (96,000,000)us-gaap_DefinedBenefitPlanBenefitsPaid
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(64,000,000)us-gaap_DefinedBenefitPlanBenefitsPaid
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Medicare subsidies received 0us-gaap_DefinedBenefitPlanGrossPrescriptionDrugSubsidyReceiptsReceived
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0us-gaap_DefinedBenefitPlanGrossPrescriptionDrugSubsidyReceiptsReceived
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Plan amendments 0iep_DefinedBenefitPlanEffectOfPlanAmendmentsOnChangeInBenefitObligation
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0iep_DefinedBenefitPlanEffectOfPlanAmendmentsOnChangeInBenefitObligation
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Curtailments 0us-gaap_DefinedBenefitPlanCurtailments
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0us-gaap_DefinedBenefitPlanCurtailments
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Settlements (3,000,000)us-gaap_DefinedBenefitPlanSettlementsBenefitObligation
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0us-gaap_DefinedBenefitPlanSettlementsBenefitObligation
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Actuarial losses (gains) and changes in actuarial assumptions 151,000,000us-gaap_DefinedBenefitPlanActuarialGainLoss
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(101,000,000)us-gaap_DefinedBenefitPlanActuarialGainLoss
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Net transfers in (out) 0us-gaap_DefinedBenefitPlanAssetsTransferredToFromPlan
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0us-gaap_DefinedBenefitPlanAssetsTransferredToFromPlan
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Currency translation 0us-gaap_DefinedBenefitPlanForeignCurrencyExchangeRateChangesBenefitObligation
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0us-gaap_DefinedBenefitPlanForeignCurrencyExchangeRateChangesBenefitObligation
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Defined Benefit Plan, Fair Value of Plan Assets 912,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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909,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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778,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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Actual return on plan assets 43,000,000us-gaap_DefinedBenefitPlanActualReturnOnPlanAssets
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138,000,000us-gaap_DefinedBenefitPlanActualReturnOnPlanAssets
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Company contributions 56,000,000us-gaap_DefinedBenefitPlanContributionsByEmployer
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60,000,000us-gaap_DefinedBenefitPlanContributionsByEmployer
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Expenses 0us-gaap_DefinedBenefitPlanAdministrationExpenses
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(3,000,000)us-gaap_DefinedBenefitPlanAdministrationExpenses
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Currency translation 0us-gaap_DefinedBenefitPlanForeignCurrencyExchangeRateChangesPlanAssets
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0us-gaap_DefinedBenefitPlanForeignCurrencyExchangeRateChangesPlanAssets
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Funded status of the plan (379,000,000)us-gaap_DefinedBenefitPlanFundedStatusOfPlan
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(275,000,000)us-gaap_DefinedBenefitPlanFundedStatusOfPlan
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Net liability recognized (379,000,000)us-gaap_DefinedBenefitPlanAmountsRecognizedInBalanceSheet
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(275,000,000)us-gaap_DefinedBenefitPlanAmountsRecognizedInBalanceSheet
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Actuarial losses included in Accumulated other comprehensive income 409,000,000iep_ActuarialLossesIncludedInAccumulatedOtherComprehensiveIncome
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242,000,000iep_ActuarialLossesIncludedInAccumulatedOtherComprehensiveIncome
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Prior service cost (credit) 0us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetPriorServiceCostCreditBeforeTax
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0us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetPriorServiceCostCreditBeforeTax
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Pension and Other Postretirement Benefit Plans, Accumulated Other Comprehensive Income (Loss), Net Gains (Losses), before Tax 409,000,000us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetGainsLossesBeforeTax
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242,000,000us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetGainsLossesBeforeTax
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Defined benefit plan, assumption used calculated projected benefit obligation, rate of compensation increase 0.00%iep_DefinedBenefitPlanAssumptionUsedCalculatedProjectedBenefitObligationRateOfCompensationIncrease
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0.00%iep_DefinedBenefitPlanAssumptionUsedCalculatedProjectedBenefitObligationRateOfCompensationIncrease
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Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Expected Long-term Return on Assets 6.95%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets
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7.45%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets
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Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Rate of Compensation Increase 0.00%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostRateOfCompensationIncrease
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0.00%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostRateOfCompensationIncrease
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Defined benefit plan, plans with projected benefit obligations in excess of plan assets, fair value of plan assets 0iep_DefinedBenefitPlanPlansWithProjectedBenefitObligationsInExcessOfPlanAssetsFairValueOfPlanAssets
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Defined Benefit Plan, Pension Plans with Accumulated Benefit Obligations in Excess of Plan Assets, Aggregate Accumulated Benefit Obligation 0us-gaap_DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateAccumulatedBenefitObligation
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/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Defined Benefit Plan, Pension Plans with Accumulated Benefit Obligations in Excess of Plan Assets, Aggregate Fair Value of Plan Assets 0us-gaap_DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
0us-gaap_DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Defined benefit plans, amount in AOCI expected to be reclassed into net periodic benefit cost in the next year, amortization of prior service credit   0iep_DefinedBenefitPlansAmountInAociExpectedToBeReclassedIntoNetPeriodicBenefitCostInNextYearAmortizationOfPriorServiceCredit
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Defined Benefit Plan, Amount to be Amortized from Accumulated Other Comprehensive Income (Loss) Next Fiscal Year   0us-gaap_DefinedBenefitPlanAmountToBeAmortizedFromAccumulatedOtherComprehensiveIncomeLossNextFiscalYear
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Defined Benefit Plan, Expected Future Benefit Payments, Year Two 84,000,000us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearTwo
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
   
Defined Benefit Plan, Expected Future Benefit Payments, Year Three 83,000,000us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearThree
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
   
Defined Benefit Plan, Expected Future Benefit Payments, Year Four 81,000,000us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFour
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
   
Defined Benefit Plan, Expected Future Benefit Payments, Year Five 82,000,000us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFive
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
   
Defined Benefit Plan, Expected Future Benefit Payments, Five Fiscal Years Thereafter 392,000,000us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsFiveFiscalYearsThereafter
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
   
Pension Benefits      
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]      
Service cost 16,000,000us-gaap_DefinedBenefitPlanServiceCost
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
16,000,000us-gaap_DefinedBenefitPlanServiceCost
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
30,000,000us-gaap_DefinedBenefitPlanServiceCost
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
Interest cost 76,000,000us-gaap_DefinedBenefitPlanInterestCost
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
69,000,000us-gaap_DefinedBenefitPlanInterestCost
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
77,000,000us-gaap_DefinedBenefitPlanInterestCost
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
Pension Benefits | Railcar and Food Packaging [Member]      
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]      
Defined Benefit Plan, Benefit Obligation 203,000,000us-gaap_DefinedBenefitPlanBenefitObligation
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_RailcarAndFoodPackagingMember
176,000,000us-gaap_DefinedBenefitPlanBenefitObligation
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_RailcarAndFoodPackagingMember
198,000,000us-gaap_DefinedBenefitPlanBenefitObligation
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_RailcarAndFoodPackagingMember
Service cost 1,000,000us-gaap_DefinedBenefitPlanServiceCost
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_RailcarAndFoodPackagingMember
1,000,000us-gaap_DefinedBenefitPlanServiceCost
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_RailcarAndFoodPackagingMember
 
Interest cost 8,000,000us-gaap_DefinedBenefitPlanInterestCost
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_RailcarAndFoodPackagingMember
8,000,000us-gaap_DefinedBenefitPlanInterestCost
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_RailcarAndFoodPackagingMember
 
Benefits paid (10,000,000)us-gaap_DefinedBenefitPlanBenefitsPaid
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_RailcarAndFoodPackagingMember
(10,000,000)us-gaap_DefinedBenefitPlanBenefitsPaid
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_RailcarAndFoodPackagingMember
 
Actuarial losses (gains) and changes in actuarial assumptions 29,000,000us-gaap_DefinedBenefitPlanActuarialGainLoss
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_RailcarAndFoodPackagingMember
(21,000,000)us-gaap_DefinedBenefitPlanActuarialGainLoss
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_RailcarAndFoodPackagingMember
 
Currency translation (1,000,000)us-gaap_DefinedBenefitPlanForeignCurrencyExchangeRateChangesBenefitObligation
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_RailcarAndFoodPackagingMember
0us-gaap_DefinedBenefitPlanForeignCurrencyExchangeRateChangesBenefitObligation
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_RailcarAndFoodPackagingMember
 
Defined Benefit Plan, Fair Value of Plan Assets 144,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_RailcarAndFoodPackagingMember
140,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_RailcarAndFoodPackagingMember
125,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_RailcarAndFoodPackagingMember
Actual return on plan assets 9,000,000us-gaap_DefinedBenefitPlanActualReturnOnPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_RailcarAndFoodPackagingMember
20,000,000us-gaap_DefinedBenefitPlanActualReturnOnPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_RailcarAndFoodPackagingMember
 
Company contributions 6,000,000us-gaap_DefinedBenefitPlanContributionsByEmployer
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_RailcarAndFoodPackagingMember
5,000,000us-gaap_DefinedBenefitPlanContributionsByEmployer
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_RailcarAndFoodPackagingMember
 
Currency translation (1,000,000)us-gaap_DefinedBenefitPlanForeignCurrencyExchangeRateChangesPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_RailcarAndFoodPackagingMember
0us-gaap_DefinedBenefitPlanForeignCurrencyExchangeRateChangesPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_RailcarAndFoodPackagingMember
 
Funded status of the plan (59,000,000)us-gaap_DefinedBenefitPlanFundedStatusOfPlan
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_RailcarAndFoodPackagingMember
(36,000,000)us-gaap_DefinedBenefitPlanFundedStatusOfPlan
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_RailcarAndFoodPackagingMember
 
Net liability recognized (59,000,000)us-gaap_DefinedBenefitPlanAmountsRecognizedInBalanceSheet
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_RailcarAndFoodPackagingMember
(36,000,000)us-gaap_DefinedBenefitPlanAmountsRecognizedInBalanceSheet
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_RailcarAndFoodPackagingMember
 
Actuarial losses included in Accumulated other comprehensive income (59,000,000)iep_ActuarialLossesIncludedInAccumulatedOtherComprehensiveIncome
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_RailcarAndFoodPackagingMember
(28,000,000)iep_ActuarialLossesIncludedInAccumulatedOtherComprehensiveIncome
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_RailcarAndFoodPackagingMember
 
Pension and Other Postretirement Benefit Plans, Accumulated Other Comprehensive Income (Loss), Net Gains (Losses), before Tax (59,000,000)us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetGainsLossesBeforeTax
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_RailcarAndFoodPackagingMember
(28,000,000)us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetGainsLossesBeforeTax
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_RailcarAndFoodPackagingMember
 
Non-U.S. Plans | Automotive Segment [Member]      
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]      
Defined Benefit Plan, Expected Future Benefit Payments, Next Twelve Months 26,000,000us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsNextTwelveMonths
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_ForeignPensionPlansDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
   
Defined benefit plans, amount in AOCI expected to be reclassed into net periodic benefit cost in the next year, amortization of actuarial losses   0iep_DefinedBenefitPlansAmountInAociExpectedToBeReclassedIntoNetPeriodicBenefitCostInNextYearAmortizationOfActuarialLosses
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_ForeignPensionPlansDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Defined Benefit Plan, Pension Plans with Accumulated Benefit Obligations in Excess of Plan Assets, Aggregate Projected Benefit Obligation 0us-gaap_DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateProjectedBenefitObligation
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_ForeignPensionPlansDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
0us-gaap_DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateProjectedBenefitObligation
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_ForeignPensionPlansDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Defined benefit plan, plans with projected benefit obligations in excess of plan assets, aggregate projected benefit obligation 0iep_DefinedBenefitPlanPlansWithProjectedBenefitObligationsInExcessOfPlanAssetsAggregateProjectedBenefitObligation
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_ForeignPensionPlansDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
0iep_DefinedBenefitPlanPlansWithProjectedBenefitObligationsInExcessOfPlanAssetsAggregateProjectedBenefitObligation
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_ForeignPensionPlansDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Discount Rate 3.49%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostDiscountRate
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_ForeignPensionPlansDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
2.99%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostDiscountRate
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_ForeignPensionPlansDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Defined benefit plan, assumption used calculated projected benefit obligation, discount rate 1.77%iep_DefinedBenefitPlanAssumptionUsedCalculatedProjectedBenefitObligationDiscountRate
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_ForeignPensionPlansDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
3.49%iep_DefinedBenefitPlanAssumptionUsedCalculatedProjectedBenefitObligationDiscountRate
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_ForeignPensionPlansDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Defined Benefit Plan, Benefit Obligation 575,000,000us-gaap_DefinedBenefitPlanBenefitObligation
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_ForeignPensionPlansDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
450,000,000us-gaap_DefinedBenefitPlanBenefitObligation
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_ForeignPensionPlansDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
474,000,000us-gaap_DefinedBenefitPlanBenefitObligation
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_ForeignPensionPlansDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
Service cost 12,000,000us-gaap_DefinedBenefitPlanServiceCost
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_ForeignPensionPlansDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
12,000,000us-gaap_DefinedBenefitPlanServiceCost
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_ForeignPensionPlansDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Interest cost 16,000,000us-gaap_DefinedBenefitPlanInterestCost
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_ForeignPensionPlansDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
14,000,000us-gaap_DefinedBenefitPlanInterestCost
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_ForeignPensionPlansDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Employee contributions 0us-gaap_DefinedBenefitPlanContributionsByPlanParticipants
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_ForeignPensionPlansDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
0us-gaap_DefinedBenefitPlanContributionsByPlanParticipants
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_ForeignPensionPlansDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Benefits paid (28,000,000)us-gaap_DefinedBenefitPlanBenefitsPaid
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_ForeignPensionPlansDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
(28,000,000)us-gaap_DefinedBenefitPlanBenefitsPaid
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_ForeignPensionPlansDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Medicare subsidies received 0us-gaap_DefinedBenefitPlanGrossPrescriptionDrugSubsidyReceiptsReceived
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_ForeignPensionPlansDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
0us-gaap_DefinedBenefitPlanGrossPrescriptionDrugSubsidyReceiptsReceived
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_ForeignPensionPlansDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Plan amendments 0iep_DefinedBenefitPlanEffectOfPlanAmendmentsOnChangeInBenefitObligation
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_ForeignPensionPlansDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
0iep_DefinedBenefitPlanEffectOfPlanAmendmentsOnChangeInBenefitObligation
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_ForeignPensionPlansDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Curtailments (1,000,000)us-gaap_DefinedBenefitPlanCurtailments
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_ForeignPensionPlansDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
(1,000,000)us-gaap_DefinedBenefitPlanCurtailments
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_ForeignPensionPlansDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Settlements 0us-gaap_DefinedBenefitPlanSettlementsBenefitObligation
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_ForeignPensionPlansDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
0us-gaap_DefinedBenefitPlanSettlementsBenefitObligation
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_ForeignPensionPlansDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Actuarial losses (gains) and changes in actuarial assumptions 112,000,000us-gaap_DefinedBenefitPlanActuarialGainLoss
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_ForeignPensionPlansDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
(25,000,000)us-gaap_DefinedBenefitPlanActuarialGainLoss
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_ForeignPensionPlansDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Net transfers in (out) 73,000,000us-gaap_DefinedBenefitPlanAssetsTransferredToFromPlan
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_ForeignPensionPlansDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
(11,000,000)us-gaap_DefinedBenefitPlanAssetsTransferredToFromPlan
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_ForeignPensionPlansDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Currency translation (59,000,000)us-gaap_DefinedBenefitPlanForeignCurrencyExchangeRateChangesBenefitObligation
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_ForeignPensionPlansDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
15,000,000us-gaap_DefinedBenefitPlanForeignCurrencyExchangeRateChangesBenefitObligation
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Defined Benefit Plan, Fair Value of Plan Assets 54,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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55,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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55,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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Actual return on plan assets 3,000,000us-gaap_DefinedBenefitPlanActualReturnOnPlanAssets
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2,000,000us-gaap_DefinedBenefitPlanActualReturnOnPlanAssets
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/ us-gaap_StatementBusinessSegmentsAxis
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Company contributions 30,000,000us-gaap_DefinedBenefitPlanContributionsByEmployer
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24,000,000us-gaap_DefinedBenefitPlanContributionsByEmployer
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Expenses 0us-gaap_DefinedBenefitPlanAdministrationExpenses
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0us-gaap_DefinedBenefitPlanAdministrationExpenses
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Currency translation (6,000,000)us-gaap_DefinedBenefitPlanForeignCurrencyExchangeRateChangesPlanAssets
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2,000,000us-gaap_DefinedBenefitPlanForeignCurrencyExchangeRateChangesPlanAssets
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Funded status of the plan (521,000,000)us-gaap_DefinedBenefitPlanFundedStatusOfPlan
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(395,000,000)us-gaap_DefinedBenefitPlanFundedStatusOfPlan
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/ us-gaap_StatementBusinessSegmentsAxis
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Net liability recognized (521,000,000)us-gaap_DefinedBenefitPlanAmountsRecognizedInBalanceSheet
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(395,000,000)us-gaap_DefinedBenefitPlanAmountsRecognizedInBalanceSheet
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/ us-gaap_StatementBusinessSegmentsAxis
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Actuarial losses included in Accumulated other comprehensive income 151,000,000iep_ActuarialLossesIncludedInAccumulatedOtherComprehensiveIncome
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
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81,000,000iep_ActuarialLossesIncludedInAccumulatedOtherComprehensiveIncome
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Prior service cost (credit) (2,000,000)us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetPriorServiceCostCreditBeforeTax
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(3,000,000)us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetPriorServiceCostCreditBeforeTax
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Pension and Other Postretirement Benefit Plans, Accumulated Other Comprehensive Income (Loss), Net Gains (Losses), before Tax 153,000,000us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetGainsLossesBeforeTax
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84,000,000us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetGainsLossesBeforeTax
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Defined benefit plan, assumption used calculated projected benefit obligation, rate of compensation increase 3.16%iep_DefinedBenefitPlanAssumptionUsedCalculatedProjectedBenefitObligationRateOfCompensationIncrease
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3.17%iep_DefinedBenefitPlanAssumptionUsedCalculatedProjectedBenefitObligationRateOfCompensationIncrease
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
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/ us-gaap_StatementBusinessSegmentsAxis
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Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Expected Long-term Return on Assets 4.18%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets
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4.62%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets
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/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Rate of Compensation Increase 3.17%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostRateOfCompensationIncrease
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
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3.13%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostRateOfCompensationIncrease
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_ForeignPensionPlansDefinedBenefitMember
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Defined benefit plan, plans with projected benefit obligations in excess of plan assets, fair value of plan assets 0iep_DefinedBenefitPlanPlansWithProjectedBenefitObligationsInExcessOfPlanAssetsFairValueOfPlanAssets
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Defined Benefit Plan, Pension Plans with Accumulated Benefit Obligations in Excess of Plan Assets, Aggregate Accumulated Benefit Obligation 0us-gaap_DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateAccumulatedBenefitObligation
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Defined Benefit Plan, Pension Plans with Accumulated Benefit Obligations in Excess of Plan Assets, Aggregate Fair Value of Plan Assets 0us-gaap_DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateFairValueOfPlanAssets
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Defined benefit plans, amount in AOCI expected to be reclassed into net periodic benefit cost in the next year, amortization of prior service credit   0iep_DefinedBenefitPlansAmountInAociExpectedToBeReclassedIntoNetPeriodicBenefitCostInNextYearAmortizationOfPriorServiceCredit
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Defined Benefit Plan, Amount to be Amortized from Accumulated Other Comprehensive Income (Loss) Next Fiscal Year   0us-gaap_DefinedBenefitPlanAmountToBeAmortizedFromAccumulatedOtherComprehensiveIncomeLossNextFiscalYear
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Defined Benefit Plan, Expected Future Benefit Payments, Year Two 25,000,000us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearTwo
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Defined Benefit Plan, Expected Future Benefit Payments, Year Three 25,000,000us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearThree
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Defined Benefit Plan, Expected Future Benefit Payments, Year Four 26,000,000us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFour
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/ us-gaap_StatementBusinessSegmentsAxis
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Defined Benefit Plan, Expected Future Benefit Payments, Year Five 27,000,000us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFive
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Defined Benefit Plan, Expected Future Benefit Payments, Five Fiscal Years Thereafter 139,000,000us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsFiveFiscalYearsThereafter
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/ us-gaap_StatementBusinessSegmentsAxis
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Other Post-Employment Benefits      
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]      
Service cost 0us-gaap_DefinedBenefitPlanServiceCost
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1,000,000us-gaap_DefinedBenefitPlanServiceCost
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= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
Interest cost 15,000,000us-gaap_DefinedBenefitPlanInterestCost
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
11,000,000us-gaap_DefinedBenefitPlanInterestCost
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
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14,000,000us-gaap_DefinedBenefitPlanInterestCost
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
Other Post-Employment Benefits | Automotive Segment [Member]      
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]      
Defined Benefit Plan, Expected Future Benefit Payments, Next Twelve Months 27,000,000us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsNextTwelveMonths
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
   
Defined benefit plans, amount in AOCI expected to be reclassed into net periodic benefit cost in the next year, amortization of actuarial losses   0iep_DefinedBenefitPlansAmountInAociExpectedToBeReclassedIntoNetPeriodicBenefitCostInNextYearAmortizationOfActuarialLosses
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
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/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Defined benefit plan, plans with projected benefit obligations in excess of plan assets, aggregate projected benefit obligation 0iep_DefinedBenefitPlanPlansWithProjectedBenefitObligationsInExcessOfPlanAssetsAggregateProjectedBenefitObligation
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/ us-gaap_StatementBusinessSegmentsAxis
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Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Discount Rate 4.45%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostDiscountRate
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/ us-gaap_StatementBusinessSegmentsAxis
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3.60%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostDiscountRate
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/ us-gaap_StatementBusinessSegmentsAxis
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Defined benefit plan, assumption used calculated projected benefit obligation, discount rate 3.84%iep_DefinedBenefitPlanAssumptionUsedCalculatedProjectedBenefitObligationDiscountRate
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
4.45%iep_DefinedBenefitPlanAssumptionUsedCalculatedProjectedBenefitObligationDiscountRate
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Defined Benefit Plan, Benefit Obligation 368,000,000us-gaap_DefinedBenefitPlanBenefitObligation
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
335,000,000us-gaap_DefinedBenefitPlanBenefitObligation
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
395,000,000us-gaap_DefinedBenefitPlanBenefitObligation
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
Service cost 0us-gaap_DefinedBenefitPlanServiceCost
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/ us-gaap_StatementBusinessSegmentsAxis
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0us-gaap_DefinedBenefitPlanServiceCost
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/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Interest cost 15,000,000us-gaap_DefinedBenefitPlanInterestCost
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11,000,000us-gaap_DefinedBenefitPlanInterestCost
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/ us-gaap_StatementBusinessSegmentsAxis
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Employee contributions 0us-gaap_DefinedBenefitPlanContributionsByPlanParticipants
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1,000,000us-gaap_DefinedBenefitPlanContributionsByPlanParticipants
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/ us-gaap_StatementBusinessSegmentsAxis
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Benefits paid (26,000,000)us-gaap_DefinedBenefitPlanBenefitsPaid
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/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
(28,000,000)us-gaap_DefinedBenefitPlanBenefitsPaid
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
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Medicare subsidies received 1,000,000us-gaap_DefinedBenefitPlanGrossPrescriptionDrugSubsidyReceiptsReceived
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/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
3,000,000us-gaap_DefinedBenefitPlanGrossPrescriptionDrugSubsidyReceiptsReceived
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
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/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Plan amendments 8,000,000iep_DefinedBenefitPlanEffectOfPlanAmendmentsOnChangeInBenefitObligation
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/ us-gaap_StatementBusinessSegmentsAxis
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Curtailments 0us-gaap_DefinedBenefitPlanCurtailments
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= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
(1,000,000)us-gaap_DefinedBenefitPlanCurtailments
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Settlements 0us-gaap_DefinedBenefitPlanSettlementsBenefitObligation
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0us-gaap_DefinedBenefitPlanSettlementsBenefitObligation
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/ us-gaap_StatementBusinessSegmentsAxis
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Actuarial losses (gains) and changes in actuarial assumptions 36,000,000us-gaap_DefinedBenefitPlanActuarialGainLoss
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/ us-gaap_StatementBusinessSegmentsAxis
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(43,000,000)us-gaap_DefinedBenefitPlanActuarialGainLoss
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
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Net transfers in (out) 0us-gaap_DefinedBenefitPlanAssetsTransferredToFromPlan
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/ us-gaap_StatementBusinessSegmentsAxis
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Actuarial losses included in Accumulated other comprehensive income 95,000,000iep_ActuarialLossesIncludedInAccumulatedOtherComprehensiveIncome
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Pension and Other Postretirement Benefit Plans, Accumulated Other Comprehensive Income (Loss), Net Gains (Losses), before Tax 81,000,000us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetGainsLossesBeforeTax
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0.00%iep_DefinedBenefitPlanAssumptionUsedCalculatedProjectedBenefitObligationRateOfCompensationIncrease
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Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Expected Long-term Return on Assets 0.00%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets
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Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Rate of Compensation Increase 0.00%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostRateOfCompensationIncrease
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Defined benefit plans, amount in AOCI expected to be reclassed into net periodic benefit cost in the next year, amortization of prior service credit   0iep_DefinedBenefitPlansAmountInAociExpectedToBeReclassedIntoNetPeriodicBenefitCostInNextYearAmortizationOfPriorServiceCredit
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Defined Benefit Plan, Amount to be Amortized from Accumulated Other Comprehensive Income (Loss) Next Fiscal Year   0us-gaap_DefinedBenefitPlanAmountToBeAmortizedFromAccumulatedOtherComprehensiveIncomeLossNextFiscalYear
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Defined Benefit Plan, Expected Future Benefit Payments, Year Two 26,000,000us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearTwo
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Defined Benefit Plan, Expected Future Benefit Payments, Year Three 27,000,000us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearThree
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Defined Benefit Plan, Expected Future Benefit Payments, Year Four 26,000,000us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFour
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Defined Benefit Plan, Expected Future Benefit Payments, Year Five 26,000,000us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFive
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Defined Benefit Plan, Expected Future Benefit Payments, Five Fiscal Years Thereafter 121,000,000us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsFiveFiscalYearsThereafter
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Other Post-Employment Benefits | Railcar and Food Packaging [Member]      
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]      
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Currency translation 0us-gaap_DefinedBenefitPlanForeignCurrencyExchangeRateChangesBenefitObligation
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Currency translation 0us-gaap_DefinedBenefitPlanForeignCurrencyExchangeRateChangesPlanAssets
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Funded status of the plan 0us-gaap_DefinedBenefitPlanFundedStatusOfPlan
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Net liability recognized 0us-gaap_DefinedBenefitPlanAmountsRecognizedInBalanceSheet
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Actuarial losses included in Accumulated other comprehensive income 1,000,000iep_ActuarialLossesIncludedInAccumulatedOtherComprehensiveIncome
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1,000,000iep_ActuarialLossesIncludedInAccumulatedOtherComprehensiveIncome
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Pension and Other Postretirement Benefit Plans, Accumulated Other Comprehensive Income (Loss), Net Gains (Losses), before Tax 1,000,000us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetGainsLossesBeforeTax
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1,000,000us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetGainsLossesBeforeTax
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25 basis point decrease in discount rate [Member] | United States Plans | Automotive Segment [Member]      
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]      
Change in pension expense due to sensitivity of assumptions used to determine projected benefit obligation, next twelve months (1,000,000)iep_ChangeInPensionExpenseDueToSensitivityOfAssumptionsUsedToDetermineProjectedBenefitObligationNextTwelveMonths
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Change in projected benefit obligation due to sensitivity of assumptions used to determine projected benefit obligation, next twelve months 36,000,000iep_ChangeInProjectedBenefitObligationDueToSensitivityOfAssumptionsUsedToDetermineProjectedBenefitObligationNextTwelveMonths
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Change in accumulated other comprehensive loss due to sensitivity of assumptions used to determine projected benefit obligation, next twelve months (36,000,000)iep_ChangeInAccumulatedOtherComprehensiveLossDueToSensitivityOfAssumptionsUsedToDetermineProjectedBenefitObligationNextTwelveMonths
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25 basis point decrease in discount rate [Member] | Non-U.S. Plans | Automotive Segment [Member]      
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]      
Change in pension expense due to sensitivity of assumptions used to determine projected benefit obligation, next twelve months 1,000,000iep_ChangeInPensionExpenseDueToSensitivityOfAssumptionsUsedToDetermineProjectedBenefitObligationNextTwelveMonths
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Change in projected benefit obligation due to sensitivity of assumptions used to determine projected benefit obligation, next twelve months 20,000,000iep_ChangeInProjectedBenefitObligationDueToSensitivityOfAssumptionsUsedToDetermineProjectedBenefitObligationNextTwelveMonths
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