v3.26.1
Financial instruments and related risk management (Related risk management) (Details) - CAD ($)
 12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Disclosure of detailed information about financial instruments [line items]      
Financial assets $ 1,595,941,000 $ 947,365,000  
Financial liabilities (1,901,557,000) (2,053,773,000)  
Gain (loss) on derivatives 95,017,000 (183,103,000)  
Disclosure of credit risk exposure [abstract]      
Cash and cash equivalents 1,114,860,000 600,462,000 $ 566,809,000
Short-term investments 99,603,000 0  
Accounts receivable 360,312,000 346,800,000  
Derivative assets $ 21,166,000 103,000  
Currency risk [Member]      
Disclosure of detailed information about financial instruments [line items]      
Percentage increase or decrease in CAD$ 5.00%    
Currency risk [Member] | Cash And Cash Equivalent [Member]      
Disclosure of detailed information about financial instruments [line items]      
Financial assets $ 207,370,000    
Gain (loss), foreign exchange 10,368,000    
Currency risk [Member] | Accounts receivable [Member]      
Disclosure of detailed information about financial instruments [line items]      
Financial assets 317,839,000    
Gain (loss), foreign exchange 15,892,000    
Currency risk [Member] | Accounts Payable And Accrued Liabilities [Member]      
Disclosure of detailed information about financial instruments [line items]      
Financial liabilities (501,457,000)    
Gain (loss), foreign exchange (25,073,000)    
Currency risk [Member] | Net Foreign Currency Derivatives [Member]      
Disclosure of detailed information about financial instruments [line items]      
Financial assets 3,922,000    
Gain (loss), foreign exchange (153,023,000)    
Interest rate risk [Member]      
Disclosure of detailed information about financial instruments [line items]      
Gain (loss) on derivatives (757,000)    
Credit risk [Member]      
Disclosure of credit risk exposure [abstract]      
Cash and cash equivalents 1,114,860,000 600,462,000  
Short-term investments 99,603,000 0  
Accounts receivable 343,974,000 318,126,000  
Derivative assets $ 21,166,000 $ 103,000