XML 54 R62.htm IDEA: XBRL DOCUMENT v2.4.1.9
Fair Value Measurements Other Segments Fair Value (Details) (USD $)
Dec. 31, 2014
Dec. 31, 2013
Dec. 31, 2012
Other Segments and Holding Company [Member] | Recurring measurement [Member]      
Assets [Abstract]      
Marketable equity and debt securities $ 153,000,000us-gaap_AvailableForSaleSecurities
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$ 1,000,000us-gaap_AvailableForSaleSecurities
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Trading securities 55,000,000us-gaap_TradingSecurities
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116,000,000us-gaap_TradingSecurities
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Derivative contracts, Assets at fair value 47,000,000us-gaap_DerivativeAssets
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[1]  
Fair value of investment and derivative assets 255,000,000us-gaap_AssetsFairValueDisclosure
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118,000,000us-gaap_AssetsFairValueDisclosure
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Liabilities [Abstract]      
Other liabilities 50,000,000us-gaap_OtherLiabilities
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[2] 16,000,000us-gaap_OtherLiabilities
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[2]  
Derivative contracts, Liabilities at fair value 2,000,000us-gaap_DerivativeLiabilities
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[2] 35,000,000us-gaap_DerivativeLiabilities
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[2]  
Fair value of investment and derivative liabilities 52,000,000us-gaap_LiabilitiesFairValueDisclosure
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51,000,000us-gaap_LiabilitiesFairValueDisclosure
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Other Segments and Holding Company [Member] | Recurring measurement [Member] | Level 1 [Member]      
Assets [Abstract]      
Marketable equity and debt securities 75,000,000us-gaap_AvailableForSaleSecurities
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1,000,000us-gaap_AvailableForSaleSecurities
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Trading securities 0us-gaap_TradingSecurities
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[1]  
Fair value of investment and derivative assets 75,000,000us-gaap_AssetsFairValueDisclosure
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Liabilities [Abstract]      
Other liabilities 0us-gaap_OtherLiabilities
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Derivative contracts, Liabilities at fair value 0us-gaap_DerivativeLiabilities
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Fair value of investment and derivative liabilities 0us-gaap_LiabilitiesFairValueDisclosure
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Other Segments and Holding Company [Member] | Recurring measurement [Member] | Level 2 [Member]      
Assets [Abstract]      
Marketable equity and debt securities 3,000,000us-gaap_AvailableForSaleSecurities
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Trading securities 0us-gaap_TradingSecurities
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Derivative contracts, Assets at fair value 47,000,000us-gaap_DerivativeAssets
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Fair value of investment and derivative assets 50,000,000us-gaap_AssetsFairValueDisclosure
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Liabilities [Abstract]      
Other liabilities 50,000,000us-gaap_OtherLiabilities
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[2] 16,000,000us-gaap_OtherLiabilities
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Derivative contracts, Liabilities at fair value 2,000,000us-gaap_DerivativeLiabilities
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[2] 35,000,000us-gaap_DerivativeLiabilities
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Fair value of investment and derivative liabilities 52,000,000us-gaap_LiabilitiesFairValueDisclosure
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Other Segments and Holding Company [Member] | Recurring measurement [Member] | Level 3 [Member]      
Assets [Abstract]      
Marketable equity and debt securities 75,000,000us-gaap_AvailableForSaleSecurities
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Trading securities 55,000,000us-gaap_TradingSecurities
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116,000,000us-gaap_TradingSecurities
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Fair value of investment and derivative assets 130,000,000us-gaap_AssetsFairValueDisclosure
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Liabilities [Abstract]      
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Railcar and Food Packaging [Member] | Recurring measurement [Member]      
Assets [Abstract]      
Defined Benefit Plan, Fair Value of Plan Assets 139,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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Railcar and Food Packaging [Member] | Recurring measurement [Member] | Level 1 [Member]      
Assets [Abstract]      
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Railcar and Food Packaging [Member] | Recurring measurement [Member] | Level 2 [Member]      
Assets [Abstract]      
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Railcar and Food Packaging [Member] | Recurring measurement [Member] | Level 3 [Member]      
Assets [Abstract]      
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United States Plans | Automotive Segment [Member]      
Assets [Abstract]      
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United States Plans | Automotive Segment [Member] | Recurring measurement [Member]      
Assets [Abstract]      
Defined Benefit Plan, Fair Value of Plan Assets 912,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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United States Plans | Automotive Segment [Member] | Recurring measurement [Member] | Level 1 [Member]      
Assets [Abstract]      
Defined Benefit Plan, Fair Value of Plan Assets 796,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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United States Plans | Automotive Segment [Member] | Recurring measurement [Member] | Level 2 [Member]      
Assets [Abstract]      
Defined Benefit Plan, Fair Value of Plan Assets 25,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
30,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
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/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
United States Plans | Automotive Segment [Member] | Recurring measurement [Member] | Level 3 [Member]      
Assets [Abstract]      
Defined Benefit Plan, Fair Value of Plan Assets 91,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
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/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
85,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Non-U.S. Plans | Automotive Segment [Member]      
Assets [Abstract]      
Defined Benefit Plan, Fair Value of Plan Assets 54,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_ForeignPensionPlansDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
55,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_ForeignPensionPlansDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
55,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_ForeignPensionPlansDefinedBenefitMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
Non-U.S. Plans | Automotive Segment [Member] | Recurring measurement [Member]      
Assets [Abstract]      
Defined Benefit Plan, Fair Value of Plan Assets 54,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_ForeignPensionPlansDefinedBenefitMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
55,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_ForeignPensionPlansDefinedBenefitMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Non-U.S. Plans | Automotive Segment [Member] | Recurring measurement [Member] | Level 1 [Member]      
Assets [Abstract]      
Defined Benefit Plan, Fair Value of Plan Assets 11,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_ForeignPensionPlansDefinedBenefitMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
9,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_ForeignPensionPlansDefinedBenefitMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Non-U.S. Plans | Automotive Segment [Member] | Recurring measurement [Member] | Level 2 [Member]      
Assets [Abstract]      
Defined Benefit Plan, Fair Value of Plan Assets 2,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_ForeignPensionPlansDefinedBenefitMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
2,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_ForeignPensionPlansDefinedBenefitMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Non-U.S. Plans | Automotive Segment [Member] | Recurring measurement [Member] | Level 3 [Member]      
Assets [Abstract]      
Defined Benefit Plan, Fair Value of Plan Assets 41,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_ForeignPensionPlansDefinedBenefitMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
44,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_ForeignPensionPlansDefinedBenefitMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Cash | Railcar and Food Packaging [Member] | Recurring measurement [Member]      
Assets [Abstract]      
Defined Benefit Plan, Fair Value of Plan Assets 6,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CashAndCashEquivalentsMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_RailcarAndFoodPackagingMember
5,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CashAndCashEquivalentsMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_RailcarAndFoodPackagingMember
 
Cash | Railcar and Food Packaging [Member] | Recurring measurement [Member] | Level 1 [Member]      
Assets [Abstract]      
Defined Benefit Plan, Fair Value of Plan Assets 5,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CashAndCashEquivalentsMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_RailcarAndFoodPackagingMember
4,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CashAndCashEquivalentsMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_RailcarAndFoodPackagingMember
 
Cash | Railcar and Food Packaging [Member] | Recurring measurement [Member] | Level 2 [Member]      
Assets [Abstract]      
Defined Benefit Plan, Fair Value of Plan Assets 1,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CashAndCashEquivalentsMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_RailcarAndFoodPackagingMember
1,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CashAndCashEquivalentsMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_RailcarAndFoodPackagingMember
 
Cash | Railcar and Food Packaging [Member] | Recurring measurement [Member] | Level 3 [Member]      
Assets [Abstract]      
Defined Benefit Plan, Fair Value of Plan Assets 0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CashAndCashEquivalentsMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_RailcarAndFoodPackagingMember
0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CashAndCashEquivalentsMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_RailcarAndFoodPackagingMember
 
Cash | United States Plans | Automotive Segment [Member] | Recurring measurement [Member]      
Assets [Abstract]      
Defined Benefit Plan, Fair Value of Plan Assets 44,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CashAndCashEquivalentsMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
33,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CashAndCashEquivalentsMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Cash | United States Plans | Automotive Segment [Member] | Recurring measurement [Member] | Level 1 [Member]      
Assets [Abstract]      
Defined Benefit Plan, Fair Value of Plan Assets 44,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CashAndCashEquivalentsMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
33,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CashAndCashEquivalentsMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Cash | United States Plans | Automotive Segment [Member] | Recurring measurement [Member] | Level 2 [Member]      
Assets [Abstract]      
Defined Benefit Plan, Fair Value of Plan Assets 0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CashAndCashEquivalentsMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CashAndCashEquivalentsMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Cash | United States Plans | Automotive Segment [Member] | Recurring measurement [Member] | Level 3 [Member]      
Assets [Abstract]      
Defined Benefit Plan, Fair Value of Plan Assets 0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CashAndCashEquivalentsMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CashAndCashEquivalentsMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Equity securities | United States Plans | Automotive Segment [Member] | Recurring measurement [Member]      
Assets [Abstract]      
Defined Benefit Plan, Fair Value of Plan Assets 314,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_EquityFundsMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
347,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_EquityFundsMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Equity securities | United States Plans | Automotive Segment [Member] | Recurring measurement [Member] | Level 1 [Member]      
Assets [Abstract]      
Defined Benefit Plan, Fair Value of Plan Assets 314,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_EquityFundsMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
347,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_EquityFundsMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Equity securities | United States Plans | Automotive Segment [Member] | Recurring measurement [Member] | Level 2 [Member]      
Assets [Abstract]      
Defined Benefit Plan, Fair Value of Plan Assets 0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_EquityFundsMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_EquityFundsMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Equity securities | United States Plans | Automotive Segment [Member] | Recurring measurement [Member] | Level 3 [Member]      
Assets [Abstract]      
Defined Benefit Plan, Fair Value of Plan Assets 0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_EquityFundsMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_EquityFundsMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Fixed income securities | Railcar and Food Packaging [Member] | Recurring measurement [Member]      
Assets [Abstract]      
Defined Benefit Plan, Fair Value of Plan Assets 23,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedIncomeSecuritiesMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_RailcarAndFoodPackagingMember
22,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedIncomeSecuritiesMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_RailcarAndFoodPackagingMember
 
Fixed income securities | Railcar and Food Packaging [Member] | Recurring measurement [Member] | Level 1 [Member]      
Assets [Abstract]      
Defined Benefit Plan, Fair Value of Plan Assets 22,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedIncomeSecuritiesMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_RailcarAndFoodPackagingMember
21,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedIncomeSecuritiesMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_RailcarAndFoodPackagingMember
 
Fixed income securities | Railcar and Food Packaging [Member] | Recurring measurement [Member] | Level 2 [Member]      
Assets [Abstract]      
Defined Benefit Plan, Fair Value of Plan Assets 1,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedIncomeSecuritiesMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_RailcarAndFoodPackagingMember
1,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedIncomeSecuritiesMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_RailcarAndFoodPackagingMember
 
Fixed income securities | Railcar and Food Packaging [Member] | Recurring measurement [Member] | Level 3 [Member]      
Assets [Abstract]      
Defined Benefit Plan, Fair Value of Plan Assets 0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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/ us-gaap_StatementBusinessSegmentsAxis
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0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedIncomeSecuritiesMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_RailcarAndFoodPackagingMember
 
Fixed income securities | United States Plans | Automotive Segment [Member] | Recurring measurement [Member]      
Assets [Abstract]      
Defined Benefit Plan, Fair Value of Plan Assets 166,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
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= iep_AutomotiveSegmentMember
135,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedIncomeSecuritiesMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Fixed income securities | United States Plans | Automotive Segment [Member] | Recurring measurement [Member] | Level 1 [Member]      
Assets [Abstract]      
Defined Benefit Plan, Fair Value of Plan Assets 166,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
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/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedIncomeSecuritiesMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
135,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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= us-gaap_FixedIncomeSecuritiesMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Fixed income securities | United States Plans | Automotive Segment [Member] | Recurring measurement [Member] | Level 2 [Member]      
Assets [Abstract]      
Defined Benefit Plan, Fair Value of Plan Assets 0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember
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/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
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/ us-gaap_StatementBusinessSegmentsAxis
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0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedIncomeSecuritiesMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Fixed income securities | United States Plans | Automotive Segment [Member] | Recurring measurement [Member] | Level 3 [Member]      
Assets [Abstract]      
Defined Benefit Plan, Fair Value of Plan Assets 0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember
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/ us-gaap_StatementBusinessSegmentsAxis
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0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
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/ us-gaap_FairValueByFairValueHierarchyLevelAxis
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/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedIncomeSecuritiesMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Fixed income securities | Non-U.S. Plans | Automotive Segment [Member] | Recurring measurement [Member]      
Assets [Abstract]      
Defined Benefit Plan, Fair Value of Plan Assets 10,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
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/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
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/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
7,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedIncomeSecuritiesMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Fixed income securities | Non-U.S. Plans | Automotive Segment [Member] | Recurring measurement [Member] | Level 1 [Member]      
Assets [Abstract]      
Defined Benefit Plan, Fair Value of Plan Assets 10,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
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/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedIncomeSecuritiesMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
7,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedIncomeSecuritiesMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Fixed income securities | Non-U.S. Plans | Automotive Segment [Member] | Recurring measurement [Member] | Level 2 [Member]      
Assets [Abstract]      
Defined Benefit Plan, Fair Value of Plan Assets 0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
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/ us-gaap_StatementBusinessSegmentsAxis
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0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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/ us-gaap_FairValueByFairValueHierarchyLevelAxis
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/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedIncomeSecuritiesMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Fixed income securities | Non-U.S. Plans | Automotive Segment [Member] | Recurring measurement [Member] | Level 3 [Member]      
Assets [Abstract]      
Defined Benefit Plan, Fair Value of Plan Assets 0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
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/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
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/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
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/ us-gaap_FairValueByFairValueHierarchyLevelAxis
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/ us-gaap_FairValueByMeasurementFrequencyAxis
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/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedIncomeSecuritiesMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Real estate and other | United States Plans | Automotive Segment [Member] | Recurring measurement [Member]      
Assets [Abstract]      
Defined Benefit Plan, Fair Value of Plan Assets 25,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
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/ us-gaap_FairValueByMeasurementFrequencyAxis
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/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
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/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
23,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= iep_RealEstateAndOtherMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Real estate and other | United States Plans | Automotive Segment [Member] | Recurring measurement [Member] | Level 1 [Member]      
Assets [Abstract]      
Defined Benefit Plan, Fair Value of Plan Assets 25,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
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/ us-gaap_FairValueByFairValueHierarchyLevelAxis
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/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= iep_RealEstateAndOtherMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
23,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
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/ us-gaap_FairValueByFairValueHierarchyLevelAxis
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/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= iep_RealEstateAndOtherMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Real estate and other | United States Plans | Automotive Segment [Member] | Recurring measurement [Member] | Level 2 [Member]      
Assets [Abstract]      
Defined Benefit Plan, Fair Value of Plan Assets 0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
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/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
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/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
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/ us-gaap_FairValueByFairValueHierarchyLevelAxis
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= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= iep_RealEstateAndOtherMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Real estate and other | United States Plans | Automotive Segment [Member] | Recurring measurement [Member] | Level 3 [Member]      
Assets [Abstract]      
Defined Benefit Plan, Fair Value of Plan Assets 0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
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/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
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/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= iep_RealEstateAndOtherMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Equity securities | Railcar and Food Packaging [Member] | Recurring measurement [Member]      
Assets [Abstract]      
Defined Benefit Plan, Fair Value of Plan Assets 83,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_EquitySecuritiesMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_RailcarAndFoodPackagingMember
81,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_EquitySecuritiesMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_RailcarAndFoodPackagingMember
 
Equity securities | Railcar and Food Packaging [Member] | Recurring measurement [Member] | Level 1 [Member]      
Assets [Abstract]      
Defined Benefit Plan, Fair Value of Plan Assets 55,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_EquitySecuritiesMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_RailcarAndFoodPackagingMember
66,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
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/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_EquitySecuritiesMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_RailcarAndFoodPackagingMember
 
Equity securities | Railcar and Food Packaging [Member] | Recurring measurement [Member] | Level 2 [Member]      
Assets [Abstract]      
Defined Benefit Plan, Fair Value of Plan Assets 28,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_EquitySecuritiesMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_RailcarAndFoodPackagingMember
15,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_EquitySecuritiesMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_RailcarAndFoodPackagingMember
 
Equity securities | Railcar and Food Packaging [Member] | Recurring measurement [Member] | Level 3 [Member]      
Assets [Abstract]      
Defined Benefit Plan, Fair Value of Plan Assets 0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_EquitySecuritiesMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_RailcarAndFoodPackagingMember
0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_EquitySecuritiesMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_RailcarAndFoodPackagingMember
 
Equity securities | United States Plans | Automotive Segment [Member] | Recurring measurement [Member]      
Assets [Abstract]      
Defined Benefit Plan, Fair Value of Plan Assets 231,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
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/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_EquitySecuritiesMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
242,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_EquitySecuritiesMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Equity securities | United States Plans | Automotive Segment [Member] | Recurring measurement [Member] | Level 1 [Member]      
Assets [Abstract]      
Defined Benefit Plan, Fair Value of Plan Assets 231,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_EquitySecuritiesMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
242,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
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/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_EquitySecuritiesMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Equity securities | United States Plans | Automotive Segment [Member] | Recurring measurement [Member] | Level 2 [Member]      
Assets [Abstract]      
Defined Benefit Plan, Fair Value of Plan Assets 0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
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/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_EquitySecuritiesMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
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/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_EquitySecuritiesMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Equity securities | United States Plans | Automotive Segment [Member] | Recurring measurement [Member] | Level 3 [Member]      
Assets [Abstract]      
Defined Benefit Plan, Fair Value of Plan Assets 0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_EquitySecuritiesMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
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/ us-gaap_FairValueByFairValueHierarchyLevelAxis
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/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_EquitySecuritiesMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Equity securities | Non-U.S. Plans | Automotive Segment [Member] | Recurring measurement [Member]      
Assets [Abstract]      
Defined Benefit Plan, Fair Value of Plan Assets 1,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
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/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_EquitySecuritiesMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
2,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_ForeignPensionPlansDefinedBenefitMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_EquitySecuritiesMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Equity securities | Non-U.S. Plans | Automotive Segment [Member] | Recurring measurement [Member] | Level 1 [Member]      
Assets [Abstract]      
Defined Benefit Plan, Fair Value of Plan Assets 1,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
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/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_EquitySecuritiesMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
2,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
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/ us-gaap_FairValueByFairValueHierarchyLevelAxis
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/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_EquitySecuritiesMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Equity securities | Non-U.S. Plans | Automotive Segment [Member] | Recurring measurement [Member] | Level 2 [Member]      
Assets [Abstract]      
Defined Benefit Plan, Fair Value of Plan Assets 0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_ForeignPensionPlansDefinedBenefitMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
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/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_EquitySecuritiesMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
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/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_EquitySecuritiesMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Equity securities | Non-U.S. Plans | Automotive Segment [Member] | Recurring measurement [Member] | Level 3 [Member]      
Assets [Abstract]      
Defined Benefit Plan, Fair Value of Plan Assets 0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_ForeignPensionPlansDefinedBenefitMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
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/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
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/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
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/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_EquitySecuritiesMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Fixed income collective trust | United States Plans | Automotive Segment [Member] | Recurring measurement [Member]      
Assets [Abstract]      
Defined Benefit Plan, Fair Value of Plan Assets 0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= iep_FixedIncomeCollectiveTrustMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
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/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= iep_FixedIncomeCollectiveTrustMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Fixed income collective trust | United States Plans | Automotive Segment [Member] | Recurring measurement [Member] | Level 1 [Member]      
Assets [Abstract]      
Defined Benefit Plan, Fair Value of Plan Assets 0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= iep_FixedIncomeCollectiveTrustMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
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/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= iep_FixedIncomeCollectiveTrustMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Fixed income collective trust | United States Plans | Automotive Segment [Member] | Recurring measurement [Member] | Level 2 [Member]      
Assets [Abstract]      
Defined Benefit Plan, Fair Value of Plan Assets 0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
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/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= iep_FixedIncomeCollectiveTrustMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
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/ us-gaap_FairValueByFairValueHierarchyLevelAxis
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/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= iep_FixedIncomeCollectiveTrustMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Fixed income collective trust | United States Plans | Automotive Segment [Member] | Recurring measurement [Member] | Level 3 [Member]      
Assets [Abstract]      
Defined Benefit Plan, Fair Value of Plan Assets 0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
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/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= iep_FixedIncomeCollectiveTrustMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= iep_FixedIncomeCollectiveTrustMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Corporate and other | United States Plans | Automotive Segment [Member] | Recurring measurement [Member]      
Assets [Abstract]      
Defined Benefit Plan, Fair Value of Plan Assets 21,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CorporateAndOtherMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
22,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
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/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CorporateAndOtherMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Corporate and other | United States Plans | Automotive Segment [Member] | Recurring measurement [Member] | Level 1 [Member]      
Assets [Abstract]      
Defined Benefit Plan, Fair Value of Plan Assets 0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
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/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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/ us-gaap_FairValueByFairValueHierarchyLevelAxis
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= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CorporateAndOtherMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Corporate and other | United States Plans | Automotive Segment [Member] | Recurring measurement [Member] | Level 2 [Member]      
Assets [Abstract]      
Defined Benefit Plan, Fair Value of Plan Assets 21,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
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/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
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/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
22,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CorporateAndOtherMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Corporate and other | United States Plans | Automotive Segment [Member] | Recurring measurement [Member] | Level 3 [Member]      
Assets [Abstract]      
Defined Benefit Plan, Fair Value of Plan Assets 0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CorporateAndOtherMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CorporateAndOtherMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Government | United States Plans | Automotive Segment [Member] | Recurring measurement [Member]      
Assets [Abstract]      
Defined Benefit Plan, Fair Value of Plan Assets 20,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_GovernmentMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
22,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_GovernmentMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Government | United States Plans | Automotive Segment [Member] | Recurring measurement [Member] | Level 1 [Member]      
Assets [Abstract]      
Defined Benefit Plan, Fair Value of Plan Assets 16,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_GovernmentMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
14,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_GovernmentMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Government | United States Plans | Automotive Segment [Member] | Recurring measurement [Member] | Level 2 [Member]      
Assets [Abstract]      
Defined Benefit Plan, Fair Value of Plan Assets 4,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_GovernmentMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
8,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_GovernmentMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Government | United States Plans | Automotive Segment [Member] | Recurring measurement [Member] | Level 3 [Member]      
Assets [Abstract]      
Defined Benefit Plan, Fair Value of Plan Assets 0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_GovernmentMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_GovernmentMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Hedge funds | United States Plans | Automotive Segment [Member] | Recurring measurement [Member]      
Assets [Abstract]      
Defined Benefit Plan, Fair Value of Plan Assets 91,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_HedgeFundsMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
85,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_HedgeFundsMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Hedge funds | United States Plans | Automotive Segment [Member] | Recurring measurement [Member] | Level 1 [Member]      
Assets [Abstract]      
Defined Benefit Plan, Fair Value of Plan Assets 0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_HedgeFundsMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_HedgeFundsMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Hedge funds | United States Plans | Automotive Segment [Member] | Recurring measurement [Member] | Level 2 [Member]      
Assets [Abstract]      
Defined Benefit Plan, Fair Value of Plan Assets 0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_HedgeFundsMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
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/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_HedgeFundsMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Hedge funds | United States Plans | Automotive Segment [Member] | Recurring measurement [Member] | Level 3 [Member]      
Assets [Abstract]      
Defined Benefit Plan, Fair Value of Plan Assets 91,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
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= us-gaap_HedgeFundsMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
85,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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/ us-gaap_FairValueByFairValueHierarchyLevelAxis
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/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_HedgeFundsMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Insurance contracts | Non-U.S. Plans | Automotive Segment [Member] | Recurring measurement [Member]      
Assets [Abstract]      
Defined Benefit Plan, Fair Value of Plan Assets 41,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
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= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= iep_InsuranceContractsMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
44,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_ForeignPensionPlansDefinedBenefitMember
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= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= iep_InsuranceContractsMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Insurance contracts | Non-U.S. Plans | Automotive Segment [Member] | Recurring measurement [Member] | Level 1 [Member]      
Assets [Abstract]      
Defined Benefit Plan, Fair Value of Plan Assets 0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
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= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= iep_InsuranceContractsMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
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/ us-gaap_FairValueByMeasurementFrequencyAxis
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/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= iep_InsuranceContractsMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Insurance contracts | Non-U.S. Plans | Automotive Segment [Member] | Recurring measurement [Member] | Level 2 [Member]      
Assets [Abstract]      
Defined Benefit Plan, Fair Value of Plan Assets 0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_ForeignPensionPlansDefinedBenefitMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
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/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= iep_InsuranceContractsMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
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/ us-gaap_FairValueByFairValueHierarchyLevelAxis
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/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= iep_InsuranceContractsMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Insurance contracts | Non-U.S. Plans | Automotive Segment [Member] | Recurring measurement [Member] | Level 3 [Member]      
Assets [Abstract]      
Defined Benefit Plan, Fair Value of Plan Assets 41,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
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/ us-gaap_FairValueByFairValueHierarchyLevelAxis
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/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= iep_InsuranceContractsMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
44,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_ForeignPensionPlansDefinedBenefitMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
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/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= iep_InsuranceContractsMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Corporate bonds | Non-U.S. Plans | Automotive Segment [Member] | Recurring measurement [Member]      
Assets [Abstract]      
Defined Benefit Plan, Fair Value of Plan Assets 2,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_ForeignPensionPlansDefinedBenefitMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CorporateBondSecuritiesMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
2,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_ForeignPensionPlansDefinedBenefitMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CorporateBondSecuritiesMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Corporate bonds | Non-U.S. Plans | Automotive Segment [Member] | Recurring measurement [Member] | Level 1 [Member]      
Assets [Abstract]      
Defined Benefit Plan, Fair Value of Plan Assets 0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_ForeignPensionPlansDefinedBenefitMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CorporateBondSecuritiesMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_ForeignPensionPlansDefinedBenefitMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CorporateBondSecuritiesMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Corporate bonds | Non-U.S. Plans | Automotive Segment [Member] | Recurring measurement [Member] | Level 2 [Member]      
Assets [Abstract]      
Defined Benefit Plan, Fair Value of Plan Assets 2,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
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/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CorporateBondSecuritiesMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
2,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CorporateBondSecuritiesMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Corporate bonds | Non-U.S. Plans | Automotive Segment [Member] | Recurring measurement [Member] | Level 3 [Member]      
Assets [Abstract]      
Defined Benefit Plan, Fair Value of Plan Assets 0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_ForeignPensionPlansDefinedBenefitMember
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/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
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/ us-gaap_StatementBusinessSegmentsAxis
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0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CorporateBondSecuritiesMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_AutomotiveSegmentMember
 
Other | Railcar and Food Packaging [Member] | Recurring measurement [Member]      
Assets [Abstract]      
Defined Benefit Plan, Fair Value of Plan Assets 27,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
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/ us-gaap_StatementBusinessSegmentsAxis
= iep_RailcarAndFoodPackagingMember
27,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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= us-gaap_OtherAggregatedInvestmentsMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_RailcarAndFoodPackagingMember
 
Other | Railcar and Food Packaging [Member] | Recurring measurement [Member] | Level 1 [Member]      
Assets [Abstract]      
Defined Benefit Plan, Fair Value of Plan Assets 6,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_OtherAggregatedInvestmentsMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_RailcarAndFoodPackagingMember
6,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_OtherAggregatedInvestmentsMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_RailcarAndFoodPackagingMember
 
Other | Railcar and Food Packaging [Member] | Recurring measurement [Member] | Level 2 [Member]      
Assets [Abstract]      
Defined Benefit Plan, Fair Value of Plan Assets 0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
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/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_OtherAggregatedInvestmentsMember
/ us-gaap_StatementBusinessSegmentsAxis
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0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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= us-gaap_FairValueMeasurementsRecurringMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_OtherAggregatedInvestmentsMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_RailcarAndFoodPackagingMember
 
Other | Railcar and Food Packaging [Member] | Recurring measurement [Member] | Level 3 [Member]      
Assets [Abstract]      
Defined Benefit Plan, Fair Value of Plan Assets $ 21,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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= us-gaap_FairValueInputsLevel3Member
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/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_OtherAggregatedInvestmentsMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_RailcarAndFoodPackagingMember
$ 21,000,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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= us-gaap_FairValueInputsLevel3Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
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= us-gaap_OtherAggregatedInvestmentsMember
/ us-gaap_StatementBusinessSegmentsAxis
= iep_RailcarAndFoodPackagingMember
 
[1] Amounts are classified within other assets in our consolidated balance sheets.
[2] Amounts are classified within accrued expenses and other liabilities in our consolidated balance sheets.