Commitments and Contingencies - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Jan. 31, 2023
Loss Contingencies [Line Items]
Environmental loss contingency accrual	$ 19	$ 22
Environmental Loss Contingency, Statement of Financial Position [Extensible Enumeration]	Accrued Liabilities	Accrued Liabilities
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	$ 34
Icahn Enterprises Holdings
Loss Contingencies [Line Items]
Affiliate ownership interest	99.00%
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	86.00%
Energy
Loss Contingencies [Line Items]
Price of RINs		$ 435
Expense (benefit)	$ 114
RFS position	329	$ 692
Insurance policies coverage limits	50
Energy | Call option lawsuits
Loss Contingencies [Line Items]
Litigation settlement paid	$ 79