[Line Items] for Description of Business

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Estimated number of railcars to be disposed of (number of railcars)

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Limited Liability Company (LLC) or Limited Partnership (LP), Managing Member or General Partner, Aggregate Ownership interest of Parent and Holding Company Subsidiaries

+ References

No definition available.

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Proceeds From Rights Offering

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- Definition

Subsidiary of Limited Liability Company (LLC) or Limited Partnership (LP), Managing Member or General Partner, Ownership Interest

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No definition available.

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- Definition

The fair value of investment held in the subsidiary investment funds by the limited liability company or limited partnership.

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No definition available.

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- Definition

Subsidiary repurchase of treasury stock

+ References

No definition available.

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- Definition

Total consideration received from sale of asset

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No definition available.

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- Definition

Value of business to be disposed of

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No definition available.

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- Definition

Value of equity interests (such as common shares, preferred shares, or partnership interest) issued or issuable to acquire the entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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-SubTopic 30
-Section 50
-Paragraph 1
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- Definition

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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- Definition

Amount of liabilities incurred by the acquirer as part of consideration transferred in a business combination.

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- Definition

Amount of gain (loss) on sale or disposal of assets, including but not limited to property plant and equipment, intangible assets and equity in securities of subsidiaries or equity method investee.

+ References

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

Percentage investment held by the managing member or general partner of the limited liability company (LLC) or limited partnership (LP).

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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- Definition

Percentage investment held by members or limited partners of limited liability company (LLC) or limited partnership (LP).

+ References

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- Definition

Amount of noncash consideration received for selling an asset or business through a noncash (or part noncash) transaction.

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

The cash outflow associated with the purchase of noncontrolling interest during the period.

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

The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

+ References

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- Definition

The cash outflow associated with the acquisition of or advances to an entity that is related to it but not strictly controlled (for example, an unconsolidated subsidiary, affiliate, and joint venture or equity method investment) or the acquisition of an additional interest in a subsidiary (controlled entity).

+ References

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The carrying amount, as of the date of the latest financial statement presented, of all assets that are pledged as collateral for the payment of the related debt obligation primarily arising from secured borrowings, repurchase agreements or other current or potential obligations, where the secured party does not have the right by contract or custom to sell or re-pledge the collateral and therefore are not reclassified and separately reported in the statement of financial position.

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Aggregate cash proceeds received from a combination of transactions in which noncurrent assets are sold, which may include the sale of a business, an investment in an affiliate (including an equity method investee), property, plant and equipment and intangible assets. Excludes sales of trading, available-for-sale, and held-to-maturity securities.

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- Definition

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

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 320
-Section S99
-Paragraph 9
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(Details) $ in Millions				1 Months Ended	12 Months Ended
(Details) $ in Millions	Apr. 01, 2016 USD ($)	Feb. 04, 2016 USD ($)	Mar. 26, 2015 USD ($)	Jan. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
Description of Business [Line Items]
Subsidiary repurchase of treasury stock					$ 36	$ 72	$ 57
Gain on disposition of assets, net					2,166	14	40
Proceeds from disposition of assets					2,064	43	90
Payments to Acquire Additional Interest in Subsidiaries					349	2	0
Seller financing secured mortgages resulting from disposition of assets					375	0	0
Automotive Segment
Description of Business [Line Items]
Gain on disposition of assets, net					12	9	0
Energy Segment
Description of Business [Line Items]
Gain on disposition of assets, net					$ (3)	0	(2)
Railcar Segment
Description of Business [Line Items]
Estimated number of railcars to be disposed of (number of railcars)					0
Gain on disposition of assets, net					$ 1,664	3	4
Value of business to be disposed of					3,300
Gaming Segment
Description of Business [Line Items]
Gain on disposition of assets, net					(4)	0	(1)
Food Packaging Segment
Description of Business [Line Items]
Gain on disposition of assets, net					0	0	(1)
Real Estate Segment
Description of Business [Line Items]
Total consideration received from sale of asset					600
Gain on disposition of assets, net					496	1	40
Proceeds from disposition of assets					225
Assets pledged as collateral					21	24
Seller financing secured mortgages resulting from disposition of assets					375
Real Estate Segment \| Fountainebleu
Description of Business [Line Items]
Gain on disposition of assets, net					456
Real Estate Segment \| Other properties
Description of Business [Line Items]
Gain on disposition of assets, net					40
Real Estate Segment \| First Mortgage
Description of Business [Line Items]
Seller financing secured mortgages resulting from disposition of assets					345
Real Estate Segment \| Second Mortgage
Description of Business [Line Items]
Seller financing secured mortgages resulting from disposition of assets					30
Holding Company
Description of Business [Line Items]
Gain on disposition of assets, net					1	0	0
Proceeds from disposition of assets					$ 1,800
Icahn Enterprises Holdings
Description of Business [Line Items]
Percentage of equity ownership in subsidiary					99.00%
Subsidiary repurchase of treasury stock					$ 36	72	57
Gain on disposition of assets, net					2,166	14	40
Proceeds from disposition of assets					2,064	43	90
Payments to Acquire Additional Interest in Subsidiaries					349	2	0
Investment Funds
Description of Business [Line Items]
Fair value of investment in subsidiary					3,000	$ 1,700
ADS and Precision Tune \| Automotive Segment
Description of Business [Line Items]
Payments to Acquire Interest in Subsidiaries and Affiliates					$ 162
Pep Boys \| Automotive Segment
Description of Business [Line Items]
Business Combination, Consideration Transferred		$ 1,200
IEH Auto \| Automotive Segment
Description of Business [Line Items]
Payments to Acquire Interest in Subsidiaries and Affiliates							325
TRW \| Automotive Segment
Description of Business [Line Items]
Payments to Acquire Interest in Subsidiaries and Affiliates							$ 374
Federal-Mogul \| Automotive Segment
Description of Business [Line Items]
Percentage of equity ownership in subsidiary					100.00%	82.00%
Payments to Acquire Additional Interest in Subsidiaries					$ 305
Payments to Acquire Interest in Subsidiaries and Affiliates			$ 230
Proceeds from rights offering			$ 250
CVR Refining
Description of Business [Line Items]
Percentage of equity ownership in subsidiary					3.90%
CVR Refining \| Energy Segment
Description of Business [Line Items]
Percentage of equity ownership in subsidiary					66.00%
CVR Nitrogen \| Energy Segment
Description of Business [Line Items]
Business Acquisition, Equity Interest Issued or Issuable, Value Assigned	$ 336
Payments to Acquire Businesses, Gross	99
Business Combination, Consideration Transferred, Liabilities Incurred	$ 368
CVR Partners \| Energy Segment
Description of Business [Line Items]
Percentage of equity ownership in subsidiary					34.00%
CVR Energy
Description of Business [Line Items]
Percentage of equity ownership in subsidiary					82.00%
ARI
Description of Business [Line Items]
Percentage of equity ownership in subsidiary					62.20%
Tropicana \| Gaming Segment
Description of Business [Line Items]
Percentage of equity ownership in subsidiary					83.90%	72.50%
Subsidiary repurchase of treasury stock					$ 36
Payments to Acquire Additional Interest in Subsidiaries					$ 95
Ferrous Resources
Description of Business [Line Items]
Percentage of equity ownership in subsidiary					77.20%
Viskase
Description of Business [Line Items]
Percentage of equity ownership in subsidiary					74.60%
Mr. Icahn and affiliates
Description of Business [Line Items]
Affiliate ownership interest					91.00%
Icahn Enterprises G.P.
Description of Business [Line Items]
General partner ownership percentage in Icahn Enterprises					1.00%
General partner ownership interest in IEH					1.00%
Aggregate general partner ownership interest of parent and operating subsidiary					1.99%
Subsequent event \| Viskase
Description of Business [Line Items]
Percentage of equity ownership in subsidiary				78.60%
Subsequent event \| Viskase \| Food Packaging Segment
Description of Business [Line Items]
Payments to Acquire Interest in Subsidiaries and Affiliates				$ 44
Proceeds from rights offering				$ 50