v3.26.1
FINANCIAL INSTRUMENTS AND FINANCIAL RISK MANAGEMENT - Liquidity risk management (Details) - CAD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
FINANCIAL INSTRUMENTS AND FINANCIAL RISK MANAGEMENT    
Accounts payable and accrued charges $ 940.5  
Amounts payable to affiliated corporations 85.4 $ 69.4
Long-term debt 6,824.3  
Interest payments on long-term debt 1,383.8  
Lease liabilities 373.3  
Interest payments on lease liabilities 39.6  
Derivative financial instruments (48.3)  
Total 9,513.2  
Less than 1 year    
FINANCIAL INSTRUMENTS AND FINANCIAL RISK MANAGEMENT    
Accounts payable and accrued charges 940.5  
Long-term debt 491.6  
Interest payments on long-term debt 199.9  
Lease liabilities 110.3  
Interest payments on lease liabilities 15.6  
Derivative financial instruments 20.1  
Total 1,778.0  
1-3 years    
FINANCIAL INSTRUMENTS AND FINANCIAL RISK MANAGEMENT    
Long-term debt 1,438.2  
Interest payments on long-term debt 477.6  
Lease liabilities 169.0  
Interest payments on lease liabilities 16.8  
Total 2,101.6  
3-5 years    
FINANCIAL INSTRUMENTS AND FINANCIAL RISK MANAGEMENT    
Long-term debt 2,086.0  
Interest payments on long-term debt 329.5  
Lease liabilities 70.3  
Interest payments on lease liabilities 4.9  
Derivative financial instruments (80.7)  
Total 2,410.0  
5 years or more    
FINANCIAL INSTRUMENTS AND FINANCIAL RISK MANAGEMENT    
Long-term debt 2,808.5  
Interest payments on long-term debt 376.8  
Lease liabilities 23.7  
Interest payments on lease liabilities 2.3  
Derivative financial instruments 12.3  
Total $ 3,223.6  
Liquidity risk management    
FINANCIAL INSTRUMENTS AND FINANCIAL RISK MANAGEMENT    
Weighted average term of the corporation's consolidated debt 4 years 8 months 12 days 4 years 8 months 12 days