Additional borrowing availability

No definition available.

Name:	iep_Additionalborrowingavailability
Namespace Prefix:	iep_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
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+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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Balance Type:	na
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 50
-Section 40
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=117329964&loc=d3e12355-112629

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+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

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Namespace Prefix:
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Balance Type:
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- Details

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Balance Type:
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- Details

Name:	us-gaap_DebtInstrumentAxis=iep_New2024NotesMember
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Balance Type:
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- Details

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Data Type:	na
Balance Type:
Period Type:

- Details

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Balance Type:
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Debt Narrative - Holding Company Debt (Details) - Holding Company - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2017	Jan. 23, 2020	Dec. 12, 2019	Sep. 06, 2019	Jun. 27, 2019	Dec. 06, 2017	Jan. 18, 2017
Debt Instrument [Line Items]
(Gain) loss on extinguishment of debt	$ (2)	$ 12
Additional borrowing availability	$ 469
6.250% senior unsecured notes due 2026
Debt Instrument [Line Items]
Debt face amount						$ 1,250
Interest rate on debt instrument						6.25%
4.750% senior unsecured notes due 2024
Debt Instrument [Line Items]
Debt face amount					$ 500
Interest rate on debt instrument					4.75%
4.750% senior unsecured notes due 2024 \| Subsequent event
Debt Instrument [Line Items]
Debt face amount			$ 600
Interest rate on debt instrument			4.75%
5.250% senior unsecured notes due 2027
Debt Instrument [Line Items]
Debt face amount				$ 750
Interest rate on debt instrument				5.25%
5.250% senior unsecured notes due 2027 \| Subsequent event
Debt Instrument [Line Items]
Debt face amount			$ 250
Interest rate on debt instrument			5.25%
6.750% senior unsecured notes due 2024
Debt Instrument [Line Items]
Debt face amount								$ 500
Interest rate on debt instrument								6.75%
6.250% senior unsecured notes due 2022
Debt Instrument [Line Items]
Debt face amount							$ 510	$ 695
Interest rate on debt instrument							6.25%	6.25%
6.375% senior unsecured notes due 2025
Debt Instrument [Line Items]
Debt face amount							$ 750
Interest rate on debt instrument							6.375%