Investment in funds

No definition available.

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- Definition

Option exercised to purchase additional railcars, number of cars

+ References

No definition available.

+ Details

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- Definition

Option exercised to purchase additional railcars

+ References

No definition available.

+ Details

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- Definition

Option to purchase additinal railcars, number of cars

+ References

No definition available.

+ Details

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- Definition

Option to purchase additional railcars

+ References

No definition available.

+ Details

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Balance Type:	credit
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- Definition

Percentage fair value of investments in Funds that is attributable to Mr. Icahn

+ References

No definition available.

+ Details

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- Definition

Related party transaction, balance

+ References

No definition available.

+ Details

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- Definition

Amount of transactions with related party during the financial reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 850

-SubTopic 10

-Section 50

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39603-107864

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 850

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 850

-SubTopic 10

-Section 50

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39622-107864

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 850

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

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- 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

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- Definition

Reflects the sum of all other revenue and income realized from sales and other transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party during the period.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The number of units or percentage investment held in the subsidiary by the limited liability company or limited partnership.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
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Period Type:	duration

- Definition

Amount of the unrecorded obligation to transfer funds in the future for fixed or minimum amounts or quantities of goods or services at fixed or minimum prices (for example, as in take-or-pay contracts or throughput contracts).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 440

-SubTopic 10

-Section 50

-Paragraph 4

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6394976&loc=d3e25336-109308

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The minimum number of units that must be purchased, in connection with an unconditional purchase obligation that has not been recognized for financial reporting purposes.

+ References

No definition available.

+ Details

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Data Type:	xbrli:decimalItemType
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- Details

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- Details

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- Details

Name:	us-gaap_RelatedPartyTransactionAxis=iep_ExpenseSharingAgreementMember
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- Details

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- Details

Name:	us-gaap_RelatedPartyTransactionAxis=us-gaap_HedgeFundsEquityMember
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- Details

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- Details

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- Details

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- Details

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- Details

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Related Party Transactions (Details) $ in Millions	3 Months Ended		6 Months Ended		12 Months Ended
Related Party Transactions (Details) $ in Millions	Jun. 30, 2015 USD ($)	Jun. 30, 2014 USD ($)	Jun. 30, 2015 USD ($)	Jun. 30, 2014 USD ($)	Dec. 31, 2014 USD ($)
Mr. Icahn and his affiliates [Member]
Related Party Transaction [Line Items]
Investment in funds			$ 245
Icahn Capital [Member] \| Expense sharing agreement [Member]
Related Party Transaction [Line Items]
Expenses charged by related party	$ 130	$ 86	$ 228	$ 102
Investment Funds [Member] \| Mr. Icahn and his affiliates [Member]
Related Party Transaction [Line Items]
Percentage fair value of investments in Funds that is attributable to Mr. Icahn			54.00%		53.00%
Investment Funds [Member] \| Mr. Icahn and his affiliates [Member] \| Investment in Funds [Member]
Related Party Transaction [Line Items]
Related party transaction, balance	5,400		$ 5,400		$ 4,800
ARI [Member]
Related Party Transaction [Line Items]
Percentage of equity ownership in subsidiary			55.60%
ARL [Member]
Related Party Transaction [Line Items]
Percentage of equity ownership in subsidiary			75.00%
ARL [Member] \| ACF [Member] \| Railcar Sales [Member]
Related Party Transaction [Line Items]
Expenses from transactions with related party	21		$ 27
Agreements with ACF [Member] \| ARI [Member] \| ACF [Member] \| Railcar component sales [Member]
Related Party Transaction [Line Items]
Expenses from transactions with related party	7	1	9	1
Agreements with ACF [Member] \| ARI [Member] \| ACF [Member] \| Railcar Sales [Member]
Related Party Transaction [Line Items]
Revenues from transactions with related party	$ 4	6	$ 6	12
Agreements with ACF [Member] \| AEP Leasing [Member] \| ACF [Member] \| Purchase of railcars [Member]
Related Party Transaction [Line Items]
Unrecorded unconditional purchase obligation, minimum quantity required	1,050		1,050
Unrecorded unconditional purchase obligation	$ 150		$ 150
Option to purchase additinal railcars, number of cars	500		500
Option to purchase additional railcars	$ 70		$ 70
Option exercised to purchase additinal railcars, number of cars	296		296
Option exercised to purchase additional railcars	$ 42		$ 42
Agreements with ACF [Member] \| ARL [Member] \| ACF [Member] \| Railcar Sales [Member]
Related Party Transaction [Line Items]
Expenses from transactions with related party	$ 0	$ 36	$ 9	$ 63