v3.26.1
Basis of Presentation and Summary of Significant Accounting Policies (Details) - USD ($)
$ in Millions
 6 Months Ended 12 Months Ended
Jun. 30, 2026
Jun. 30, 2025
Dec. 31, 2025
Basis of Presentation and Summary of Significant Accounting Policies      
Total Assets $ 12,890   $ 14,215
Debt 6,389   6,616
Fair value of long-term debt 6,200   6,300
Restricted cash 1,971   1,969
TEB LLC      
Basis of Presentation and Summary of Significant Accounting Policies      
Carrying amount of equity method investment 84   74
Carrying value of equity investment and related party loan receivable $ 220   203
Icahn Enterprises Holdings      
Basis of Presentation and Summary of Significant Accounting Policies      
Percentage of equity ownership in operating subsidiary 99.00%    
Cash held at consolidated affiliated partnerships      
Basis of Presentation and Summary of Significant Accounting Policies      
Restricted cash $ 741   746
Restricted cash      
Basis of Presentation and Summary of Significant Accounting Policies      
Restricted cash 1,200   1,200
Primary beneficiary      
Basis of Presentation and Summary of Significant Accounting Policies      
Total Assets 115   113
Energy      
Basis of Presentation and Summary of Significant Accounting Policies      
Total Assets 4,469   4,129
Debt 1,783   1,765
Remaining performance obligation expected to be recognized as revenue within one year 2    
Deferred revenue 49   44
Recorded revenue 19 $ 47  
Automotive Segment      
Basis of Presentation and Summary of Significant Accounting Policies      
Total Assets 1,290   1,248
Debt 25   21
Restricted cash 10   8
Deferred revenue 24   $ 28
Recorded revenue $ 9 $ 11  
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2025-07-01      
Basis of Presentation and Summary of Significant Accounting Policies      
Remaining performance obligation for contracts with an original expected duration of more than one year 6 months    
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2025-07-01 | Energy      
Basis of Presentation and Summary of Significant Accounting Policies      
Remaining performance obligation expected to be recognized as revenue within one year $ 1    
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2027-01-01      
Basis of Presentation and Summary of Significant Accounting Policies      
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]: 2027-01-01 | Energy | Maximum      
Basis of Presentation and Summary of Significant Accounting Policies      
Remaining performance obligation for contracts with an original expected duration of more than one year $ 1