v3.26.1
Property, Plant and Equipment, Net (Schedule of Property, Plant and Equipment) (Details) - USD ($)
$ in Millions
Mar. 31, 2026
Dec. 31, 2025
Property, Plant and Equipment [Line Items]    
Property, Plant and Equipment, Cost $ 74,855 $ 71,431
Less: Accumulated depreciation, depletion and amortization (58,926) (57,187)
Property, plant and equipment, net 15,929 14,244
Operating Segments [Member] | USA Operations [Member]    
Property, Plant and Equipment [Line Items]    
Property, Plant and Equipment, Cost 51,334 50,909
Less: Accumulated depreciation, depletion and amortization (40,742) (39,296)
Property, plant and equipment, net 10,592 11,613
Operating Segments [Member] | Canadian Operations [Member]    
Property, Plant and Equipment [Line Items]    
Property, Plant and Equipment, Cost 22,699 19,690
Less: Accumulated depreciation, depletion and amortization (17,466) (17,168)
Property, plant and equipment, net 5,233 2,522
Corporate & Other [Member]    
Property, Plant and Equipment [Line Items]    
Property, plant and equipment, net 104 109
Proved Properties [Member] | Operating Segments [Member] | USA Operations [Member]    
Property, Plant and Equipment [Line Items]    
Property, Plant and Equipment, Cost 51,169 50,573
Less: Accumulated depreciation, depletion and amortization (40,740) (39,294)
Property, plant and equipment, net 10,429 11,279
Proved Properties [Member] | Operating Segments [Member] | Canadian Operations [Member]    
Property, Plant and Equipment [Line Items]    
Property, Plant and Equipment, Cost 21,900 19,560
Less: Accumulated depreciation, depletion and amortization (17,460) (17,163)
Property, plant and equipment, net 4,440 2,397
Unproved Properties [Member] | Operating Segments [Member] | USA Operations [Member]    
Property, Plant and Equipment [Line Items]    
Property, Plant and Equipment, Cost 146 316
Less: Accumulated depreciation, depletion and amortization 0 0
Property, plant and equipment, net 146 316
Unproved Properties [Member] | Operating Segments [Member] | Canadian Operations [Member]    
Property, Plant and Equipment [Line Items]    
Property, Plant and Equipment, Cost 668 118
Less: Accumulated depreciation, depletion and amortization 0 0
Property, plant and equipment, net 668 118
Other Capitalized Property Plant and Equipment [Member] | Operating Segments [Member] | USA Operations [Member]    
Property, Plant and Equipment [Line Items]    
Property, Plant and Equipment, Cost 19 20
Less: Accumulated depreciation, depletion and amortization (2) (2)
Property, plant and equipment, net 17 18
Other Capitalized Property Plant and Equipment [Member] | Operating Segments [Member] | Canadian Operations [Member]    
Property, Plant and Equipment [Line Items]    
Property, Plant and Equipment, Cost 131 12
Less: Accumulated depreciation, depletion and amortization (6) (5)
Property, plant and equipment, net 125 7
Other Capitalized Property Plant and Equipment [Member] | Corporate & Other [Member]    
Property, Plant and Equipment [Line Items]    
Property, Plant and Equipment, Cost 822 832
Less: Accumulated depreciation, depletion and amortization (718) (723)
Property, plant and equipment, net $ 104 $ 109