v3.25.2
Related Party Transactions (Details) - USD ($)
$ in Millions
3 Months Ended 6 Months Ended
Jun. 30, 2025
Mar. 31, 2025
Jun. 30, 2024
Mar. 31, 2024
Jun. 30, 2025
Jun. 30, 2024
Dec. 31, 2024
Related Party Transaction [Line Items]              
Cash distributions $ 1,500 $ 700 $ 1,600 $ 500 $ 2,200 $ 2,100  
Equity Method Investments and Joint Ventures [Abstract]              
Equity Method Investments Related to TTX $ 909       $ 909   $ 891
TTX Company              
Related Party Transaction [Line Items]              
Ownership Percentage in TTX Company 17.40%       17.40%    
TTX Company              
Related Party Transaction [Line Items]              
Car Hire Expenditures with TTX $ 107   $ 101   $ 213 198  
Parent Company              
Related Party Transaction [Line Items]              
Cash distributions         2,200 2,100  
Tax payments to Berkshire         699 581  
Tax refunds from Berkshire         0 $ 0  
Tax Payable, Berkshire $ 43       $ 43    
Payable, Berkshire             $ 86