v3.25.2
Property, plant and equipment (Detail) - USD ($)
$ in Millions
Jun. 30, 2025
Dec. 31, 2024
Insurance and Other [Member]    
Property, Plant and Equipment [Line Items]    
Property, plant and equipment, gross $ 60,437 $ 58,711
Property, plant and equipment, accumulated depreciation (30,063) (28,640)
Total property, plant and equipment, net 30,374 30,071
Insurance and Other [Member] | Land, buildings and improvements [Member]    
Property, Plant and Equipment [Line Items]    
Property, plant and equipment, gross 21,287 20,735
Insurance and Other [Member] | Machinery and equipment [Member]    
Property, Plant and Equipment [Line Items]    
Property, plant and equipment, gross 33,235 32,475
Insurance and Other [Member] | Furniture, fixtures and other [Member]    
Property, Plant and Equipment [Line Items]    
Property, plant and equipment, gross 5,915 5,501
Railroad [Member]    
Property, Plant and Equipment [Line Items]    
Property, plant and equipment, gross 92,967 91,672
Property, plant and equipment, accumulated depreciation (21,459) (20,411)
Total property, plant and equipment, net 71,508 71,261
Railroad [Member] | Land, track structure and other roadway [Member]    
Property, Plant and Equipment [Line Items]    
Property, plant and equipment, gross 75,413 74,093
Railroad [Member] | Locomotives, freight cars and other equipment [Member]    
Property, Plant and Equipment [Line Items]    
Property, plant and equipment, gross 15,513 15,766
Railroad [Member] | Construction in progress [Member]    
Property, Plant and Equipment [Line Items]    
Property, plant and equipment, gross 2,041 1,813
Utilities and Energy [Member]    
Property, Plant and Equipment [Line Items]    
Property, plant and equipment, gross 152,969 146,885
Property, plant and equipment, accumulated depreciation (45,111) (43,116)
Total property, plant and equipment, net 107,858 103,769
Utilities and Energy [Member] | Utility generation, transmission and distribution systems [Member]    
Property, Plant and Equipment [Line Items]    
Property, plant and equipment, gross 106,067 103,015
Utilities and Energy [Member] | Interstate natural gas pipeline assets [Member]    
Property, Plant and Equipment [Line Items]    
Property, plant and equipment, gross 20,432 20,237
Utilities and Energy [Member] | Independent power plants and other [Member]    
Property, Plant and Equipment [Line Items]    
Property, plant and equipment, gross 15,578 14,840
Utilities and Energy [Member] | Construction in progress [Member]    
Property, Plant and Equipment [Line Items]    
Property, plant and equipment, gross 10,892 8,793
Railroad, Utilities and Energy [Member]    
Property, Plant and Equipment [Line Items]    
Total property, plant and equipment, net $ 179,366 $ 175,030