v3.26.3
RISK MANAGEMENT AND FINANCIAL INSTRUMENTS - Schedule of the Consolidated Statements of Financial Position Location and Carrying Value of Derivative Instruments (Details) - CAD ($)
$ in Millions
Sep. 30, 2026
Dec. 31, 2025
TOTAL DERIVATIVE INSTRUMENTS    
Total net derivative asset/(liability) $ (1,678) $ (823)
Derivative asset liability, amounts available for offset 0 0
Total net derivative asset/(liability) $ (1,678) (823)
Debt and Equity Securities, Fair Value by Fair Value Hierarchy Level [Extensible Enumeration] Long-Term Investments  
Non- Qualifying Derivative Instruments    
TOTAL DERIVATIVE INSTRUMENTS    
Total net derivative asset/(liability) $ (1,232) (873)
Cash flow hedges | Designated as hedging instrument    
TOTAL DERIVATIVE INSTRUMENTS    
Total net derivative asset/(liability) 180 79
Fair value hedges | Designated as hedging instrument    
TOTAL DERIVATIVE INSTRUMENTS    
Total net derivative asset/(liability) (626) (29)
Foreign exchange contracts    
TOTAL DERIVATIVE INSTRUMENTS    
Total net derivative asset/(liability) (1,616) (1,104)
Derivative asset liability, amounts available for offset 0 0
Total net derivative asset/(liability) (1,616) (1,104)
Foreign exchange contracts | Non- Qualifying Derivative Instruments    
TOTAL DERIVATIVE INSTRUMENTS    
Total net derivative asset/(liability) (1,616) 1,104
Foreign exchange contracts | Cash flow hedges | Designated as hedging instrument    
TOTAL DERIVATIVE INSTRUMENTS    
Total net derivative asset/(liability) 0 0
Foreign exchange contracts | Fair value hedges | Designated as hedging instrument    
TOTAL DERIVATIVE INSTRUMENTS    
Total net derivative asset/(liability) 0 0
Interest rate contracts    
TOTAL DERIVATIVE INSTRUMENTS    
Total net derivative asset/(liability) (97) 91
Derivative asset liability, amounts available for offset 0 0
Total net derivative asset/(liability) (97) 91
Interest rate contracts | Non- Qualifying Derivative Instruments    
TOTAL DERIVATIVE INSTRUMENTS    
Total net derivative asset/(liability) 349 41
Interest rate contracts | Cash flow hedges | Designated as hedging instrument    
TOTAL DERIVATIVE INSTRUMENTS    
Total net derivative asset/(liability) 180 79
Interest rate contracts | Fair value hedges | Designated as hedging instrument    
TOTAL DERIVATIVE INSTRUMENTS    
Total net derivative asset/(liability) (626) (29)
Commodity contracts    
TOTAL DERIVATIVE INSTRUMENTS    
Total net derivative asset/(liability) 35 190
Derivative asset liability, amounts available for offset 0 0
Total net derivative asset/(liability) 35 190
Commodity contracts | Non- Qualifying Derivative Instruments    
TOTAL DERIVATIVE INSTRUMENTS    
Total net derivative asset/(liability) 35 190
Commodity contracts | Cash flow hedges | Designated as hedging instrument    
TOTAL DERIVATIVE INSTRUMENTS    
Total net derivative asset/(liability) 0 0
Commodity contracts | Fair value hedges | Designated as hedging instrument    
TOTAL DERIVATIVE INSTRUMENTS    
Total net derivative asset/(liability) 0 0
Location, Statement of Financial Position, Balance [Axis]: us-gaap:DeferredCostsAndOtherAssets    
TOTAL DERIVATIVE INSTRUMENTS    
Derivative assets, total gross derivative instruments as presented 860 293
Derivative assets, amounts available for offset (724) (71)
Derivative assets, total net derivative instruments $ 136 $ 222
Derivative Asset, Statement of Financial Position [Extensible Enumeration] Deferred Costs and Other Assets Deferred Costs and Other Assets
Location, Statement of Financial Position, Balance [Axis]: us-gaap:DeferredCostsAndOtherAssets | Non- Qualifying Derivative Instruments    
TOTAL DERIVATIVE INSTRUMENTS    
Derivative assets, total gross derivative instruments as presented $ 792 $ 284
Location, Statement of Financial Position, Balance [Axis]: us-gaap:DeferredCostsAndOtherAssets | Cash flow hedges | Designated as hedging instrument    
TOTAL DERIVATIVE INSTRUMENTS    
Derivative assets, total gross derivative instruments as presented 68 9
Location, Statement of Financial Position, Balance [Axis]: us-gaap:DeferredCostsAndOtherAssets | Fair value hedges | Designated as hedging instrument    
TOTAL DERIVATIVE INSTRUMENTS    
Derivative assets, total gross derivative instruments as presented 0 0
Location, Statement of Financial Position, Balance [Axis]: us-gaap:DeferredCostsAndOtherAssets | Foreign exchange contracts    
TOTAL DERIVATIVE INSTRUMENTS    
Derivative assets, total gross derivative instruments as presented 28 52
Derivative assets, amounts available for offset (25) (24)
Derivative assets, total net derivative instruments 3 28
Location, Statement of Financial Position, Balance [Axis]: us-gaap:DeferredCostsAndOtherAssets | Foreign exchange contracts | Non- Qualifying Derivative Instruments    
TOTAL DERIVATIVE INSTRUMENTS    
Derivative assets, total gross derivative instruments as presented 28 52
Location, Statement of Financial Position, Balance [Axis]: us-gaap:DeferredCostsAndOtherAssets | Foreign exchange contracts | Cash flow hedges | Designated as hedging instrument    
TOTAL DERIVATIVE INSTRUMENTS    
Derivative assets, total gross derivative instruments as presented 0 0
Location, Statement of Financial Position, Balance [Axis]: us-gaap:DeferredCostsAndOtherAssets | Foreign exchange contracts | Fair value hedges | Designated as hedging instrument    
TOTAL DERIVATIVE INSTRUMENTS    
Derivative assets, total gross derivative instruments as presented 0 0
Location, Statement of Financial Position, Balance [Axis]: us-gaap:DeferredCostsAndOtherAssets | Interest rate contracts    
TOTAL DERIVATIVE INSTRUMENTS    
Derivative assets, total gross derivative instruments as presented 691 117
Derivative assets, amounts available for offset (635) (27)
Derivative assets, total net derivative instruments 56 90
Location, Statement of Financial Position, Balance [Axis]: us-gaap:DeferredCostsAndOtherAssets | Interest rate contracts | Non- Qualifying Derivative Instruments    
TOTAL DERIVATIVE INSTRUMENTS    
Derivative assets, total gross derivative instruments as presented 623 108
Location, Statement of Financial Position, Balance [Axis]: us-gaap:DeferredCostsAndOtherAssets | Interest rate contracts | Cash flow hedges | Designated as hedging instrument    
TOTAL DERIVATIVE INSTRUMENTS    
Derivative assets, total gross derivative instruments as presented 68 9
Location, Statement of Financial Position, Balance [Axis]: us-gaap:DeferredCostsAndOtherAssets | Interest rate contracts | Fair value hedges | Designated as hedging instrument    
TOTAL DERIVATIVE INSTRUMENTS    
Derivative assets, total gross derivative instruments as presented 0 0
Location, Statement of Financial Position, Balance [Axis]: us-gaap:DeferredCostsAndOtherAssets | Commodity contracts    
TOTAL DERIVATIVE INSTRUMENTS    
Derivative assets, total gross derivative instruments as presented 141 124
Derivative assets, amounts available for offset (64) (20)
Derivative assets, total net derivative instruments 77 104
Location, Statement of Financial Position, Balance [Axis]: us-gaap:DeferredCostsAndOtherAssets | Commodity contracts | Non- Qualifying Derivative Instruments    
TOTAL DERIVATIVE INSTRUMENTS    
Derivative assets, total gross derivative instruments as presented 141 124
Location, Statement of Financial Position, Balance [Axis]: us-gaap:DeferredCostsAndOtherAssets | Commodity contracts | Cash flow hedges | Designated as hedging instrument    
TOTAL DERIVATIVE INSTRUMENTS    
Derivative assets, total gross derivative instruments as presented 0 0
Location, Statement of Financial Position, Balance [Axis]: us-gaap:DeferredCostsAndOtherAssets | Commodity contracts | Fair value hedges | Designated as hedging instrument    
TOTAL DERIVATIVE INSTRUMENTS    
Derivative assets, total gross derivative instruments as presented 0 0
Location, Statement of Financial Position, Balance [Axis]: us-gaap:OtherAssetsCurrent    
TOTAL DERIVATIVE INSTRUMENTS    
Derivative assets, total gross derivative instruments as presented 1,407 591
Derivative assets, amounts available for offset (898) (246)
Derivative assets, total net derivative instruments $ 509 $ 345
Derivative Asset, Statement of Financial Position [Extensible Enumeration] Other current assets Other current assets
Location, Statement of Financial Position, Balance [Axis]: us-gaap:OtherAssetsCurrent | Non- Qualifying Derivative Instruments    
TOTAL DERIVATIVE INSTRUMENTS    
Derivative assets, total gross derivative instruments as presented $ 1,280 $ 507
Location, Statement of Financial Position, Balance [Axis]: us-gaap:OtherAssetsCurrent | Cash flow hedges | Designated as hedging instrument    
TOTAL DERIVATIVE INSTRUMENTS    
Derivative assets, total gross derivative instruments as presented 112 79
Location, Statement of Financial Position, Balance [Axis]: us-gaap:OtherAssetsCurrent | Fair value hedges | Designated as hedging instrument    
TOTAL DERIVATIVE INSTRUMENTS    
Derivative assets, total gross derivative instruments as presented 15 5
Location, Statement of Financial Position, Balance [Axis]: us-gaap:OtherAssetsCurrent | Foreign exchange contracts    
TOTAL DERIVATIVE INSTRUMENTS    
Derivative assets, total gross derivative instruments as presented 81 27
Derivative assets, amounts available for offset (52) (17)
Derivative assets, total net derivative instruments 29 10
Location, Statement of Financial Position, Balance [Axis]: us-gaap:OtherAssetsCurrent | Foreign exchange contracts | Non- Qualifying Derivative Instruments    
TOTAL DERIVATIVE INSTRUMENTS    
Derivative assets, total gross derivative instruments as presented 81 27
Location, Statement of Financial Position, Balance [Axis]: us-gaap:OtherAssetsCurrent | Foreign exchange contracts | Cash flow hedges | Designated as hedging instrument    
TOTAL DERIVATIVE INSTRUMENTS    
Derivative assets, total gross derivative instruments as presented 0 0
Location, Statement of Financial Position, Balance [Axis]: us-gaap:OtherAssetsCurrent | Foreign exchange contracts | Fair value hedges | Designated as hedging instrument    
TOTAL DERIVATIVE INSTRUMENTS    
Derivative assets, total gross derivative instruments as presented 0 0
Location, Statement of Financial Position, Balance [Axis]: us-gaap:OtherAssetsCurrent | Interest rate contracts    
TOTAL DERIVATIVE INSTRUMENTS    
Derivative assets, total gross derivative instruments as presented 187 106
Derivative assets, amounts available for offset (28) (37)
Derivative assets, total net derivative instruments 159 69
Location, Statement of Financial Position, Balance [Axis]: us-gaap:OtherAssetsCurrent | Interest rate contracts | Non- Qualifying Derivative Instruments    
TOTAL DERIVATIVE INSTRUMENTS    
Derivative assets, total gross derivative instruments as presented 60 22
Location, Statement of Financial Position, Balance [Axis]: us-gaap:OtherAssetsCurrent | Interest rate contracts | Cash flow hedges | Designated as hedging instrument    
TOTAL DERIVATIVE INSTRUMENTS    
Derivative assets, total gross derivative instruments as presented 112 79
Location, Statement of Financial Position, Balance [Axis]: us-gaap:OtherAssetsCurrent | Interest rate contracts | Fair value hedges | Designated as hedging instrument    
TOTAL DERIVATIVE INSTRUMENTS    
Derivative assets, total gross derivative instruments as presented 15 5
Location, Statement of Financial Position, Balance [Axis]: us-gaap:OtherAssetsCurrent | Commodity contracts    
TOTAL DERIVATIVE INSTRUMENTS    
Derivative assets, total gross derivative instruments as presented 1,139 458
Derivative assets, amounts available for offset (818) (192)
Derivative assets, total net derivative instruments 321 266
Location, Statement of Financial Position, Balance [Axis]: us-gaap:OtherAssetsCurrent | Commodity contracts | Non- Qualifying Derivative Instruments    
TOTAL DERIVATIVE INSTRUMENTS    
Derivative assets, total gross derivative instruments as presented 1,139 458
Location, Statement of Financial Position, Balance [Axis]: us-gaap:OtherAssetsCurrent | Commodity contracts | Cash flow hedges | Designated as hedging instrument    
TOTAL DERIVATIVE INSTRUMENTS    
Derivative assets, total gross derivative instruments as presented 0 0
Location, Statement of Financial Position, Balance [Axis]: us-gaap:OtherAssetsCurrent | Commodity contracts | Fair value hedges | Designated as hedging instrument    
TOTAL DERIVATIVE INSTRUMENTS    
Derivative assets, total gross derivative instruments as presented 0 0
Location, Statement of Financial Position, Balance [Axis]: us-gaap:OtherLiabilitiesCurrent    
TOTAL DERIVATIVE INSTRUMENTS    
Derivative liabilities, total gross derivative instruments as presented (1,813) (712)
Derivative liabilities, amounts available for offset 898 246
Derivative liabilities, total net derivative instruments $ (915) $ (466)
Derivative Liability, Statement of Financial Position [Extensible Enumeration] Other current liabilities Other current liabilities
Location, Statement of Financial Position, Balance [Axis]: us-gaap:OtherLiabilitiesCurrent | Non- Qualifying Derivative Instruments    
TOTAL DERIVATIVE INSTRUMENTS    
Derivative liabilities, total gross derivative instruments as presented $ (1,804) $ (703)
Location, Statement of Financial Position, Balance [Axis]: us-gaap:OtherLiabilitiesCurrent | Cash flow hedges | Designated as hedging instrument    
TOTAL DERIVATIVE INSTRUMENTS    
Derivative liabilities, total gross derivative instruments as presented 0 (9)
Location, Statement of Financial Position, Balance [Axis]: us-gaap:OtherLiabilitiesCurrent | Fair value hedges | Designated as hedging instrument    
TOTAL DERIVATIVE INSTRUMENTS    
Derivative liabilities, total gross derivative instruments as presented (9) 0
Location, Statement of Financial Position, Balance [Axis]: us-gaap:OtherLiabilitiesCurrent | Foreign exchange contracts    
TOTAL DERIVATIVE INSTRUMENTS    
Derivative liabilities, total gross derivative instruments as presented (664) (364)
Derivative liabilities, amounts available for offset 52 17
Derivative liabilities, total net derivative instruments (612) (347)
Location, Statement of Financial Position, Balance [Axis]: us-gaap:OtherLiabilitiesCurrent | Foreign exchange contracts | Non- Qualifying Derivative Instruments    
TOTAL DERIVATIVE INSTRUMENTS    
Derivative liabilities, total gross derivative instruments as presented (664) (364)
Location, Statement of Financial Position, Balance [Axis]: us-gaap:OtherLiabilitiesCurrent | Foreign exchange contracts | Cash flow hedges | Designated as hedging instrument    
TOTAL DERIVATIVE INSTRUMENTS    
Derivative liabilities, total gross derivative instruments as presented 0 0
Location, Statement of Financial Position, Balance [Axis]: us-gaap:OtherLiabilitiesCurrent | Foreign exchange contracts | Fair value hedges | Designated as hedging instrument    
TOTAL DERIVATIVE INSTRUMENTS    
Derivative liabilities, total gross derivative instruments as presented 0 0
Location, Statement of Financial Position, Balance [Axis]: us-gaap:OtherLiabilitiesCurrent | Interest rate contracts    
TOTAL DERIVATIVE INSTRUMENTS    
Derivative liabilities, total gross derivative instruments as presented (30) (48)
Derivative liabilities, amounts available for offset 28 37
Derivative liabilities, total net derivative instruments (2) (11)
Location, Statement of Financial Position, Balance [Axis]: us-gaap:OtherLiabilitiesCurrent | Interest rate contracts | Non- Qualifying Derivative Instruments    
TOTAL DERIVATIVE INSTRUMENTS    
Derivative liabilities, total gross derivative instruments as presented (21) (39)
Location, Statement of Financial Position, Balance [Axis]: us-gaap:OtherLiabilitiesCurrent | Interest rate contracts | Cash flow hedges | Designated as hedging instrument    
TOTAL DERIVATIVE INSTRUMENTS    
Derivative liabilities, total gross derivative instruments as presented 0 (9)
Location, Statement of Financial Position, Balance [Axis]: us-gaap:OtherLiabilitiesCurrent | Interest rate contracts | Fair value hedges | Designated as hedging instrument    
TOTAL DERIVATIVE INSTRUMENTS    
Derivative liabilities, total gross derivative instruments as presented (9) 0
Location, Statement of Financial Position, Balance [Axis]: us-gaap:OtherLiabilitiesCurrent | Commodity contracts    
TOTAL DERIVATIVE INSTRUMENTS    
Derivative liabilities, total gross derivative instruments as presented (1,119) (300)
Derivative liabilities, amounts available for offset 818 192
Derivative liabilities, total net derivative instruments (301) (108)
Location, Statement of Financial Position, Balance [Axis]: us-gaap:OtherLiabilitiesCurrent | Commodity contracts | Non- Qualifying Derivative Instruments    
TOTAL DERIVATIVE INSTRUMENTS    
Derivative liabilities, total gross derivative instruments as presented (1,119) (300)
Location, Statement of Financial Position, Balance [Axis]: us-gaap:OtherLiabilitiesCurrent | Commodity contracts | Cash flow hedges | Designated as hedging instrument    
TOTAL DERIVATIVE INSTRUMENTS    
Derivative liabilities, total gross derivative instruments as presented 0 0
Location, Statement of Financial Position, Balance [Axis]: us-gaap:OtherLiabilitiesCurrent | Commodity contracts | Fair value hedges | Designated as hedging instrument    
TOTAL DERIVATIVE INSTRUMENTS    
Derivative liabilities, total gross derivative instruments as presented 0 0
Location, Statement of Financial Position, Balance [Axis]: us-gaap:OtherLiabilitiesNoncurrent    
TOTAL DERIVATIVE INSTRUMENTS    
Derivative liabilities, total gross derivative instruments as presented (2,132) (995)
Derivative liabilities, amounts available for offset 724 71
Derivative liabilities, total net derivative instruments $ (1,408) $ (924)
Derivative Liability, Statement of Financial Position [Extensible Enumeration] Other Liabilities, Noncurrent Other Liabilities, Noncurrent
Location, Statement of Financial Position, Balance [Axis]: us-gaap:OtherLiabilitiesNoncurrent | Non- Qualifying Derivative Instruments    
TOTAL DERIVATIVE INSTRUMENTS    
Derivative liabilities, total gross derivative instruments as presented $ (1,500) $ (961)
Location, Statement of Financial Position, Balance [Axis]: us-gaap:OtherLiabilitiesNoncurrent | Cash flow hedges | Designated as hedging instrument    
TOTAL DERIVATIVE INSTRUMENTS    
Derivative liabilities, total gross derivative instruments as presented 0 0
Location, Statement of Financial Position, Balance [Axis]: us-gaap:OtherLiabilitiesNoncurrent | Fair value hedges | Designated as hedging instrument    
TOTAL DERIVATIVE INSTRUMENTS    
Derivative liabilities, total gross derivative instruments as presented (632) (34)
Location, Statement of Financial Position, Balance [Axis]: us-gaap:OtherLiabilitiesNoncurrent | Foreign exchange contracts    
TOTAL DERIVATIVE INSTRUMENTS    
Derivative liabilities, total gross derivative instruments as presented (1,061) (819)
Derivative liabilities, amounts available for offset 25 24
Derivative liabilities, total net derivative instruments (1,036) (795)
Location, Statement of Financial Position, Balance [Axis]: us-gaap:OtherLiabilitiesNoncurrent | Foreign exchange contracts | Non- Qualifying Derivative Instruments    
TOTAL DERIVATIVE INSTRUMENTS    
Derivative liabilities, total gross derivative instruments as presented (1,061) (819)
Location, Statement of Financial Position, Balance [Axis]: us-gaap:OtherLiabilitiesNoncurrent | Foreign exchange contracts | Cash flow hedges | Designated as hedging instrument    
TOTAL DERIVATIVE INSTRUMENTS    
Derivative liabilities, total gross derivative instruments as presented 0 0
Location, Statement of Financial Position, Balance [Axis]: us-gaap:OtherLiabilitiesNoncurrent | Foreign exchange contracts | Fair value hedges | Designated as hedging instrument    
TOTAL DERIVATIVE INSTRUMENTS    
Derivative liabilities, total gross derivative instruments as presented 0 0
Location, Statement of Financial Position, Balance [Axis]: us-gaap:OtherLiabilitiesNoncurrent | Interest rate contracts    
TOTAL DERIVATIVE INSTRUMENTS    
Derivative liabilities, total gross derivative instruments as presented (945) (84)
Derivative liabilities, amounts available for offset 635 27
Derivative liabilities, total net derivative instruments (310) (57)
Location, Statement of Financial Position, Balance [Axis]: us-gaap:OtherLiabilitiesNoncurrent | Interest rate contracts | Non- Qualifying Derivative Instruments    
TOTAL DERIVATIVE INSTRUMENTS    
Derivative liabilities, total gross derivative instruments as presented (313) (50)
Location, Statement of Financial Position, Balance [Axis]: us-gaap:OtherLiabilitiesNoncurrent | Interest rate contracts | Cash flow hedges | Designated as hedging instrument    
TOTAL DERIVATIVE INSTRUMENTS    
Derivative liabilities, total gross derivative instruments as presented 0 0
Location, Statement of Financial Position, Balance [Axis]: us-gaap:OtherLiabilitiesNoncurrent | Interest rate contracts | Fair value hedges | Designated as hedging instrument    
TOTAL DERIVATIVE INSTRUMENTS    
Derivative liabilities, total gross derivative instruments as presented (632) (34)
Location, Statement of Financial Position, Balance [Axis]: us-gaap:OtherLiabilitiesNoncurrent | Commodity contracts    
TOTAL DERIVATIVE INSTRUMENTS    
Derivative liabilities, total gross derivative instruments as presented (126) (92)
Derivative liabilities, amounts available for offset 64 20
Derivative liabilities, total net derivative instruments (62) (72)
Location, Statement of Financial Position, Balance [Axis]: us-gaap:OtherLiabilitiesNoncurrent | Commodity contracts | Non- Qualifying Derivative Instruments    
TOTAL DERIVATIVE INSTRUMENTS    
Derivative liabilities, total gross derivative instruments as presented (126) (92)
Location, Statement of Financial Position, Balance [Axis]: us-gaap:OtherLiabilitiesNoncurrent | Commodity contracts | Cash flow hedges | Designated as hedging instrument    
TOTAL DERIVATIVE INSTRUMENTS    
Derivative liabilities, total gross derivative instruments as presented 0 0
Location, Statement of Financial Position, Balance [Axis]: us-gaap:OtherLiabilitiesNoncurrent | Commodity contracts | Fair value hedges | Designated as hedging instrument    
TOTAL DERIVATIVE INSTRUMENTS    
Derivative liabilities, total gross derivative instruments as presented $ 0 $ 0