v3.25.4
Financial and derivative instruments - Narrative (Detail) - CAD ($)
$ in Millions
Dec. 31, 2025
Dec. 31, 2024
Financial Instruments And Derivatives [Line Items]    
Long term debt $ 3,447 $ 3,447
Master netting arrangements    
Financial Instruments And Derivatives [Line Items]    
Derivative collateral receivable $ 6 $ 22