Commitments and Contingencies (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Mr. Icahn and affiliates
Loss Contingencies [Line Items]
Affiliate ownership interest			92.00%
ACF
Loss Contingencies [Line Items]
Defined benefit plan underfunded amount	$ 64		$ 64
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	(2)	$ 20	$ 31	$ 47
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	$ 34		$ 34		$ 37