Basis of Presentation and Summary of Significant Accounting Policies (Details) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Mar. 31, 2025	Mar. 31, 2024	Dec. 31, 2024
Accounting Policies [Line Items]
Total Assets	$ 15,481		$ 16,279
Debt	6,794		6,809
Fair value of long-term debt	6,500		6,600
Restricted cash	2,692		2,636
Impairment	$ 10
Icahn Enterprises Holdings
Accounting Policies [Line Items]
Percentage of equity ownership in operating subsidiary	99.00%
Cash held at consolidated affiliated partnerships
Accounting Policies [Line Items]
Restricted cash	$ 897		915
Restricted cash
Accounting Policies [Line Items]
Restricted cash	1,800		1,700
Primary beneficiary
Accounting Policies [Line Items]
Total Assets	109		108
Energy
Accounting Policies [Line Items]
Total Assets	4,722		4,751
Debt	1,918		1,919
Remaining performance obligation expected to be recognized as revenue within one year	7
Deferred revenue	62		78
Recorded revenue	23	$ 5
Automotive Segment
Accounting Policies [Line Items]
Total Assets	1,881		1,939
Debt	28		31
Restricted cash	3		8
Deferred revenue	34		37
Recorded revenue	$ 6		$ 6
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2025-01-01
Accounting Policies [Line Items]
Remaining performance obligation for contracts with an original expected duration of more than one year	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2025-01-01 | Energy
Accounting Policies [Line Items]
Remaining performance obligation expected to be recognized as revenue within one year	$ 3
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2026-01-01
Accounting Policies [Line Items]
Remaining performance obligation for contracts with an original expected duration of more than one year	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2026-01-01 | Energy
Accounting Policies [Line Items]
Remaining performance obligation for contracts with an original expected duration of more than one year	$ 3