v3.26.1
revenue from contracts with customers - Revenues (Details) - Minimum - CAD ($)
$ in Millions
Jun. 30, 2026
Dec. 31, 2025
Disclosure of transaction price allocated to remaining performance obligations    
Transaction price allocated to remaining performance obligations $ 3,352 $ 3,498
The 12-month period ending one year hence    
Disclosure of transaction price allocated to remaining performance obligations    
Transaction price allocated to remaining performance obligations 2,318 2,399
The 12-month period ending two years hence    
Disclosure of transaction price allocated to remaining performance obligations    
Transaction price allocated to remaining performance obligations 913 972
Thereafter    
Disclosure of transaction price allocated to remaining performance obligations    
Transaction price allocated to remaining performance obligations $ 121 $ 127