Commitments and Contingencies - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023	Jan. 31, 2023
Loss Contingencies [Line Items]
Environmental loss contingency accrual	$ 5		$ 19
Minimum Carbon Dioxide Supply				$ 15
Maximum fee payable				$ 45
Starfire Holding Corporation
Loss Contingencies [Line Items]
Ownership percentage by principal owner	99.60%
Pension funding indemnity agreement with subsidiary	$ 250
ACF
Loss Contingencies [Line Items]
Funded status of related party pension plan	$ 39
Icahn Enterprises Holdings | ACF | Minimum
Loss Contingencies [Line Items]
Ownership percentage by principal owner	80.00%
Mr. Icahn and affiliates | Minimum
Loss Contingencies [Line Items]
Affiliate ownership interest	80.00%
Mr. Icahn and affiliates | Icahn Enterprises G.P.
Loss Contingencies [Line Items]
Affiliate ownership in parent company general partner	100.00%
Mr. Icahn and affiliates | Icahn Enterprises Holdings
Loss Contingencies [Line Items]
Affiliate ownership interest	85.00%
Energy
Loss Contingencies [Line Items]
Expense (benefit)	$ 51	$ 11
RFS position	294		$ 329
Insurance policies coverage limits	$ 50