v3.25.4
Retirement benefits - Assets allocations (Details)
Dec. 31, 2025
Dec. 31, 2024
Disclosure of fair value of plan assets [line items]    
Debt instruments, percentage contributed to fair value of plan assets 46.00% 49.00%
Alternative Investment, percentage contributed to fair value of plan assets 25.00% 25.00%
Other assets, percentage contributed to fair value of plan assets 4.00% 5.00%
Total 100.00% 100.00%
Minimum    
Disclosure of fair value of plan assets [line items]    
Debt instruments, percentage contributed to fair value of plan assets 30.00%  
Alternative Investments, percentage contributed to fair value of plan assets 0.00%  
Maximum    
Disclosure of fair value of plan assets [line items]    
Debt instruments, percentage contributed to fair value of plan assets 75.00%  
Alternative Investments, percentage contributed to fair value of plan assets 57.00%  
Canadian    
Disclosure of fair value of plan assets [line items]    
Equities 6.00% 5.00%
Canadian | Minimum    
Disclosure of fair value of plan assets [line items]    
Equities 2.00%  
Canadian | Maximum    
Disclosure of fair value of plan assets [line items]    
Equities 15.00%  
Foreign    
Disclosure of fair value of plan assets [line items]    
Equities 19.00% 16.00%
Foreign | Minimum    
Disclosure of fair value of plan assets [line items]    
Equities 10.00%  
Foreign | Maximum    
Disclosure of fair value of plan assets [line items]    
Equities 44.00%