v3.26.1
Investments (Details)
$ in Millions
3 Months Ended 12 Months Ended
Mar. 31, 2026
USD ($)
railroad
Mar. 31, 2025
USD ($)
Dec. 31, 2025
USD ($)
Schedule of Investments [Line Items]      
Other liabilities $ 1,724   $ 1,723
Number of railroads | railroad 6    
Purchased services and rents $ 522 $ 498  
Conrail, Economic      
Schedule of Investments [Line Items]      
Equity method investment, ownership (as a percent) 58.00%    
Conrail, Voting      
Schedule of Investments [Line Items]      
Equity method investment, ownership (as a percent) 50.00%    
Conrail Inc      
Schedule of Investments [Line Items]      
Equity method investments $ 1,800   1,800
Expenses for operation of the Shared Assets Areas 52 49  
Equity in the earnings of investee 19 16  
Other liabilities $ 534   $ 534
Due to affiliate, average interest rate (as a percent) 1.31%   1.31%
TTX Company      
Schedule of Investments [Line Items]      
Equity method investment, ownership (as a percent) 19.78%    
Equity in the earnings of investee $ 8 11  
Purchased services and rents $ 76 $ 74