v3.26.1
Properties (Details) - USD ($)
$ in Millions
Mar. 31, 2026
Dec. 31, 2025
Property, Plant and Equipment [Line Items]    
Cost $ 87,040 $ 86,404
Accumulated depreciation 27,085 26,759
Net book value 59,955 59,645
Land    
Property, Plant and Equipment [Line Items]    
Cost 5,475 5,471
Net book value 5,475 5,471
Total road    
Property, Plant and Equipment [Line Items]    
Cost 64,129 63,782
Accumulated depreciation 20,908 20,630
Net book value 43,221 43,152
Rail and other track material    
Property, Plant and Equipment [Line Items]    
Cost 19,831 19,747
Accumulated depreciation 8,016 7,936
Net book value $ 11,815 $ 11,811
Estimated useful life 43 years 45 years
Ties    
Property, Plant and Equipment [Line Items]    
Cost $ 12,893 $ 12,779
Accumulated depreciation 4,361 4,305
Net book value $ 8,532 $ 8,474
Estimated useful life 34 years 34 years
Ballast    
Property, Plant and Equipment [Line Items]    
Cost $ 6,686 $ 6,646
Accumulated depreciation 2,345 2,309
Net book value $ 4,341 $ 4,337
Estimated useful life 34 years 34 years
Other roadway    
Property, Plant and Equipment [Line Items]    
Cost $ 24,719 $ 24,610
Accumulated depreciation 6,186 6,080
Net book value $ 18,533 $ 18,530
Estimated useful life 47 years 47 years
Total equipment    
Property, Plant and Equipment [Line Items]    
Cost $ 14,492 $ 14,324
Accumulated depreciation 5,489 5,460
Net book value 9,003 8,864
Locomotives    
Property, Plant and Equipment [Line Items]    
Cost 10,059 9,926
Accumulated depreciation 3,801 3,813
Net book value $ 6,258 $ 6,113
Estimated useful life 17 years 18 years
Freight cars    
Property, Plant and Equipment [Line Items]    
Cost $ 3,090 $ 3,080
Accumulated depreciation 1,133 1,107
Net book value $ 1,957 $ 1,973
Estimated useful life 23 years 23 years
Work equipment and other    
Property, Plant and Equipment [Line Items]    
Cost $ 1,343 $ 1,318
Accumulated depreciation 555 540
Net book value $ 788 $ 778
Estimated useful life 17 years 17 years
Technology and other    
Property, Plant and Equipment [Line Items]    
Cost $ 1,430 $ 1,414
Accumulated depreciation 688 669
Net book value $ 742 $ 745
Estimated useful life 12 years 12 years
Construction in progress    
Property, Plant and Equipment [Line Items]    
Cost $ 1,514 $ 1,413
Net book value $ 1,514 $ 1,413