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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Namespace Prefix:	iep_
Data Type:	xbrli:decimalItemType
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- Definition

Option exercised to purchase additional railcars

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

Option to purchase additinal railcars, number of cars

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Option to purchase additional railcars

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

Name:	iep_PercentagefairvalueofinvestmentsinFundsthatisattributabletoMr.Icahn
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- Definition

Related party transaction, balance

+ References

No definition available.

+ Details

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Namespace Prefix:	iep_
Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- 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 4

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

Reference 2: 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

Reference 3: 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

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- 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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- Details

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Balance Type:	na
Period Type:	duration

- 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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Namespace Prefix:	us-gaap_
Data Type:	xbrli:decimalItemType
Balance Type:	na
Period Type:	instant

- Details

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- Details

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- Details

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- Details

Name:	dei_LegalEntityAxis=iep_InvestmentFundsMember
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- Details

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- Details

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Related Party Transactions (Details) (USD $)	3 Months Ended		12 Months Ended
Related Party Transactions (Details) (USD $)	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Mr. Icahn and his affiliates [Member]
Related Party Transaction [Line Items]
Investment in funds	$ 245,000,000
Icahn Capital [Member] \| Expense sharing agreement [Member]
Related Party Transaction [Line Items]
Expenses charged by related party	98,000,000	16,000,000
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	5,200,000,000		4,800,000,000
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	5,000,000
Agreements with ACF [Member] \| ARI [Member] \| ACF [Member] \| Railcar Sales [Member]
Related Party Transaction [Line Items]
Revenues from transactions with related party	2,000,000	6,000,000
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
Unrecorded unconditional purchase obligation	150,000,000
Option to purchase additinal railcars, number of cars	500
Option to purchase additional railcars	70,000,000
Option exercised to purchase additinal railcars, number of cars	296
Option exercised to purchase additional railcars	42,000,000
Agreements with ACF [Member] \| ARL [Member] \| ACF [Member] \| Railcar Sales [Member]
Related Party Transaction [Line Items]
Expenses from transactions with related party	$ 9,000,000	$ 28,000,000