v3.26.3
RISK MANAGEMENT AND FINANCIAL INSTRUMENTS - Schedule of Credit Concentrations and Maximum Credit Exposure, With Respect to Derivative Instruments (Details) - Derivative Instruments - CAD ($)
$ in Millions
9 Months Ended 12 Months Ended
Sep. 30, 2026
Dec. 31, 2025
LIQUIDITY RISK AND CREDIT RISK    
Maximum credit exposure with respect to derivative instruments $ 2,236 $ 858
Canadian financial institutions    
LIQUIDITY RISK AND CREDIT RISK    
Maximum credit exposure with respect to derivative instruments 415 200
US financial institutions    
LIQUIDITY RISK AND CREDIT RISK    
Maximum credit exposure with respect to derivative instruments 904 260
European financial institutions    
LIQUIDITY RISK AND CREDIT RISK    
Maximum credit exposure with respect to derivative instruments 206 57
Asian financial institutions    
LIQUIDITY RISK AND CREDIT RISK    
Maximum credit exposure with respect to derivative instruments 208 39
Other    
LIQUIDITY RISK AND CREDIT RISK    
Maximum credit exposure with respect to derivative instruments $ 503 $ 302