Commitments and Contingencies (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended		9 Months Ended
	Oct. 31, 2020	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
ACF
Loss Contingencies [Line Items]
Defined benefit plan underfunded amount		$ 80		$ 80
Starfire Holding Corporation
Loss Contingencies [Line Items]
Ownership percentage by Mr. Icahn		99.60%		99.60%
Pension funding indemnity agreement with subsidiary		$ 250		$ 250
Energy Segment
Loss Contingencies [Line Items]
RINs costs		36	$ 2	$ 71	$ 31
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		$ 38		$ 38		$ 34
Icahn Enterprises Holdings
Loss Contingencies [Line Items]
Percentage of equity ownership in operating subsidiary	89.00%			99.00%
Icahn Enterprises Holdings | Mr. Icahn and affiliates
Loss Contingencies [Line Items]
Affiliate ownership interest				92.00%