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Expenses incurred to purchase additional renewable identification numbers

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Ownership percentage by principal owner in related party

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Represents the information pertaining to renewable fuel standard obligation (RFS).

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Subsidiary Indemnity Agreement, Pension Funding Contingencies As A Result of Being In The Controlled Group, Distribution Limitation, Net Worth Floor

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Total costs accrued as of the balance sheet date for environmental loss contingencies.

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Amount of funded (unfunded) status of defined benefit plan, measured as difference between fair value of plan assets and benefit obligation. Includes, but is not limited to, overfunded (underfunded) status.

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

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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.

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

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Commitments and Contingencies (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
ACF
Loss Contingencies [Line Items]
Defined benefit plan underfunded amount	$ 122
Starfire Holding Corporation
Loss Contingencies [Line Items]
Ownership percentage by Mr. Icahn	99.60%
Pension funding indemnity agreement with subsidiary	$ 250
Energy Segment
Loss Contingencies [Line Items]
RINs costs	178	$ 19
RFS obligation	$ 342		$ 214
Icahn Enterprises G.P. \| Mr. Icahn and affiliates
Loss Contingencies [Line Items]
Affiliate ownership in parent company general partner	100.00%
Accrued expenses and other liabilities
Loss Contingencies [Line Items]
Accrued environmental liabilities	$ 36		$ 37
Icahn Enterprises Holdings
Loss Contingencies [Line Items]
Percentage of equity ownership in operating subsidiary	99.00%
Icahn Enterprises Holdings \| Mr. Icahn and affiliates
Loss Contingencies [Line Items]
Affiliate ownership interest	91.00%