v3.25.4
LONG-TERM DEBT - Summary of Long-term Debt (Details)
Dec. 31, 2025
CAD ($)
Dec. 31, 2025
USD ($)
Apr. 30, 2025
CAD ($)
Mar. 31, 2025
USD ($)
Feb. 28, 2025
CAD ($)
Feb. 28, 2025
USD ($)
Dec. 31, 2024
CAD ($)
Feb. 29, 2024
Disclosure of detailed information about borrowings [line items]                
Long-term debt $ 35,872,000,000           $ 38,200,000,000  
Deferred transaction costs and discounts (795,000,000)           (951,000,000)  
Deferred government grant liability (79,000,000)           (39,000,000)  
Less current portion (1,186,000,000)           (3,696,000,000)  
Canada Infrastructure Bank Credit Facility due 2052 1.000%                
Disclosure of detailed information about borrowings [line items]                
Long-term debt $ 71,000,000           64,000,000  
Canada Infrastructure Bank Credit Facility due 2052 1.000% | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Interest rate 1.00% 1.00%            
Senior Notes Due 2025 - 2.950%                
Disclosure of detailed information about borrowings [line items]                
Principal amount       $ 1,000,000,000        
Interest rate       2.95%        
Senior Notes Due 2025 - 2.950% | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Principal amount   $ 1,000,000,000            
Interest rate 2.95% 2.95%            
Senior Notes Due 2025 - 3.100%                
Disclosure of detailed information about borrowings [line items]                
Principal amount     $ 1,250,000,000          
Interest rate     3.10%          
Senior Notes Due 2025 - 3.100% | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Principal amount $ 1,250,000,000              
Interest rate 3.10% 3.10%            
Senior Notes Due 2025 - 3.625%                
Disclosure of detailed information about borrowings [line items]                
Principal amount $ 700,000,000 $ 700,000,000            
Interest rate 3.625% 3.625%            
Senior Notes Due 2025 - 3.625% | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Principal amount   $ 700,000,000            
Interest rate 3.625% 3.625%            
Senior Notes Due 2026 - 5.650% | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Principal amount $ 500,000,000              
Interest rate 5.65% 5.65%            
Senior Notes Due 2026 - 2.900% | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Principal amount   $ 500,000,000            
Interest rate 2.90% 2.90%            
Senior Notes Due 2027 - 3.800% | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Principal amount $ 300,000,000              
Interest rate 3.80% 3.80%            
Senior Notes Due 2027 - 3.650% | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Principal amount $ 1,500,000,000              
Interest rate 3.65% 3.65%            
Senior Notes Due 2027 - 3.200% | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Principal amount   $ 1,300,000,000            
Interest rate 3.20% 3.20%            
Senior Notes Due 2028 - 5.700% | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Principal amount $ 1,000,000,000              
Interest rate 5.70% 5.70%            
Senior Notes Due 2028 - 4.400% | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Principal amount $ 500,000,000              
Interest rate 4.40% 4.40%            
Senior Notes Due 2029 - 5.000%                
Disclosure of detailed information about borrowings [line items]                
Interest rate               5.00%
Senior Notes Due 2029 - 5.000% | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Principal amount   $ 1,250,000,000         $ 1,250,000,000  
Interest rate 5.00% 5.00%         5.00%  
Senior Notes Due 2029 - 3.750% | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Principal amount $ 1,000,000,000              
Interest rate 3.75% 3.75%            
Senior Notes Due 2029 - 3.250% | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Principal amount $ 700,000,000              
Interest rate 3.25% 3.25%            
Senior Notes Due 2029 - 3.300% | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Principal amount $ 159,000,000              
Interest rate 3.30% 3.30%            
Senior Notes Due 2030 - 5.800% | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Principal amount $ 500,000,000              
Interest rate 5.80% 5.80%            
Senior Notes Due 2030 - 2.900% | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Principal amount $ 210,000,000              
Interest rate 2.90% 2.90%            
Senior Notes Due 2032 - 3.800% | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Principal amount   $ 2,000,000,000            
Interest rate 3.80% 3.80%            
Senior Notes Due 2032 - 4.250% | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Principal amount $ 1,000,000,000              
Interest rate 4.25% 4.25%            
Senior Debentures Due 2032 - 8.750% | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Principal amount   $ 200,000,000            
Interest rate 8.75% 8.75%            
Senior Notes Due 2033 - 5.900% | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Principal amount $ 1,000,000,000              
Interest rate 5.90% 5.90%            
Senior Notes Due 2034 - 5.300%                
Disclosure of detailed information about borrowings [line items]                
Interest rate               5.30%
Senior Notes Due 2034 - 5.300% | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Principal amount   $ 1,250,000,000         $ 1,250,000,000  
Interest rate 5.30% 5.30%         5.30%  
Senior Notes Due 2038 - 7.500% | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Principal amount   $ 350,000,000            
Interest rate 7.50% 7.50%            
Senior Notes Due 2039 - 6.680% | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Principal amount $ 500,000,000              
Interest rate 6.68% 6.68%            
Senior Notes Due 2039 - 6.750% | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Principal amount $ 1,450,000,000              
Interest rate 6.75% 6.75%            
Senior Notes Due 2040 - 6.110% | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Principal amount $ 800,000,000              
Interest rate 6.11% 6.11%            
Senior Notes Due 2041 - 6.560% | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Principal amount $ 400,000,000              
Interest rate 6.56% 6.56%            
Senior Notes Due 2042 - 4.500% | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Principal amount   $ 750,000,000            
Interest rate 4.50% 4.50%            
Senior Notes Due 2043 - 4.500% | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Principal amount   $ 382,000,000            
Interest rate 4.50% 4.50%            
Senior Notes Due 2043 - 5.450% | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Principal amount   $ 650,000,000            
Interest rate 5.45% 5.45%            
Senior Notes Due 2044 - 5.000% | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Principal amount   $ 752,000,000            
Interest rate 5.00% 5.00%            
Senior Notes Due 2048 - 4.300% | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Principal amount   $ 506,000,000            
Interest rate 4.30% 4.30%            
Senior Notes Due 2049 - 4.250% | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Principal amount   $ 630,000,000            
Interest rate 4.35% 4.35%            
Senior Notes Due 2049 - 4.350% | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Principal amount   $ 541,000,000            
Interest rate 3.70% 3.70%            
Senior Notes Due 2049 - 3.700% | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Principal amount $ 26,000,000              
Interest rate 4.25% 4.25%            
Senior Notes Due 2052 - 4.550% | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Principal amount   $ 2,000,000,000            
Interest rate 4.55% 4.55%            
Senior Notes Due 2052 - 5.250% | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Principal amount $ 1,000,000,000              
Interest rate 5.25% 5.25%            
Subordinated Notes Due 2055 - 7.00%, Tranche One                
Disclosure of detailed information about borrowings [line items]                
Principal amount           $ 1,100,000,000    
Interest rate         7.00% 7.00%    
Subordinated Notes Due 2055 - 7.00%, Tranche One | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Principal amount   $ 1,100,000,000            
Interest rate 7.00% 7.00%            
Subordinated Notes Due 2055 - 7.125%, Tranche Two                
Disclosure of detailed information about borrowings [line items]                
Principal amount           $ 1,000,000,000    
Interest rate         7.125% 7.125%    
Subordinated Notes Due 2055 - 7.125%, Tranche Two | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Principal amount   $ 1,000,000,000            
Interest rate 7.125% 7.125%            
Subordinated Notes Due 2055 - 5.625%, Tranche Three                
Disclosure of detailed information about borrowings [line items]                
Principal amount         $ 1,000,000,000      
Interest rate         5.625% 5.625%    
Subordinated Notes Due 2055 - 5.625%, Tranche Three | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Principal amount $ 1,000,000,000 $ 1,000,000,000            
Interest rate 5.625% 5.625%            
Subordinated Notes Due 2081 - 5.000% | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Principal amount $ 2,000,000,000              
Interest rate 5.00% 5.00%            
Subordinated Notes Due 2082 - 5.250% | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Principal amount   $ 750,000,000            
Interest rate 5.25% 5.25%            
Gross carrying amount                
Disclosure of detailed information about borrowings [line items]                
Long-term debt $ 37,932,000,000           $ 42,886,000,000  
Gross carrying amount | Bank credit facilities (Cdn$ portion) | Floating interest rate                
Disclosure of detailed information about borrowings [line items]                
Long-term debt 415,000,000           0  
Gross carrying amount | Term Loan Facilities | Floating interest rate                
Disclosure of detailed information about borrowings [line items]                
Long-term debt 0           1,001,000,000  
Gross carrying amount | Canada Infrastructure Bank Credit Facility due 2052 1.000% | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Long-term debt 134,000,000           64,000,000  
Gross carrying amount | Senior Notes Due 2025 - 2.950% | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Long-term debt 0           1,439,000,000  
Gross carrying amount | Senior Notes Due 2025 - 3.100% | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Long-term debt 0           1,250,000,000  
Gross carrying amount | Senior Notes Due 2025 - 3.625% | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Long-term debt 0           1,007,000,000  
Gross carrying amount | Senior Notes Due 2026 - 5.650% | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Long-term debt 500,000,000           500,000,000  
Gross carrying amount | Senior Notes Due 2026 - 2.900% | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Long-term debt 686,000,000           718,000,000  
Gross carrying amount | Senior Notes Due 2027 - 3.800% | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Long-term debt 300,000,000           300,000,000  
Gross carrying amount | Senior Notes Due 2027 - 3.650% | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Long-term debt 1,500,000,000           1,500,000,000  
Gross carrying amount | Senior Notes Due 2027 - 3.200% | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Long-term debt 1,784,000,000           1,871,000,000  
Gross carrying amount | Senior Notes Due 2028 - 5.700% | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Long-term debt 1,000,000,000           1,000,000,000  
Gross carrying amount | Senior Notes Due 2028 - 4.400% | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Long-term debt 500,000,000           500,000,000  
Gross carrying amount | Senior Notes Due 2029 - 5.000% | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Long-term debt 1,716,000,000           1,799,000,000  
Gross carrying amount | Senior Notes Due 2029 - 3.750% | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Long-term debt 1,000,000,000           1,000,000,000  
Gross carrying amount | Senior Notes Due 2029 - 3.250% | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Long-term debt 700,000,000           1,000,000,000  
Gross carrying amount | Senior Notes Due 2029 - 3.300% | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Long-term debt 159,000,000           500,000,000  
Gross carrying amount | Senior Notes Due 2030 - 5.800% | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Long-term debt 500,000,000           500,000,000  
Gross carrying amount | Senior Notes Due 2030 - 2.900% | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Long-term debt 210,000,000           500,000,000  
Gross carrying amount | Senior Notes Due 2032 - 3.800% | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Long-term debt 2,745,000,000           2,878,000,000  
Gross carrying amount | Senior Notes Due 2032 - 4.250% | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Long-term debt 1,000,000,000           1,000,000,000  
Gross carrying amount | Senior Debentures Due 2032 - 8.750% | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Long-term debt 275,000,000           288,000,000  
Gross carrying amount | Senior Notes Due 2033 - 5.900% | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Long-term debt 1,000,000,000           1,000,000,000  
Gross carrying amount | Senior Notes Due 2034 - 5.300% | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Long-term debt 1,716,000,000           1,799,000,000  
Gross carrying amount | Senior Notes Due 2038 - 7.500% | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Long-term debt 480,000,000           504,000,000  
Gross carrying amount | Senior Notes Due 2039 - 6.680% | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Long-term debt 500,000,000           500,000,000  
Gross carrying amount | Senior Notes Due 2039 - 6.750% | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Long-term debt 1,450,000,000           1,450,000,000  
Gross carrying amount | Senior Notes Due 2040 - 6.110% | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Long-term debt 800,000,000           800,000,000  
Gross carrying amount | Senior Notes Due 2041 - 6.560% | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Long-term debt 400,000,000           400,000,000  
Gross carrying amount | Senior Notes Due 2042 - 4.500% | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Long-term debt 1,029,000,000           1,079,000,000  
Gross carrying amount | Senior Notes Due 2043 - 4.500% | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Long-term debt 524,000,000           719,000,000  
Gross carrying amount | Senior Notes Due 2043 - 5.450% | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Long-term debt 892,000,000           935,000,000  
Gross carrying amount | Senior Notes Due 2044 - 5.000% | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Long-term debt 1,032,000,000           1,511,000,000  
Gross carrying amount | Senior Notes Due 2048 - 4.300% | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Long-term debt 694,000,000           1,079,000,000  
Gross carrying amount | Senior Notes Due 2049 - 4.250% | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Long-term debt 865,000,000           1,799,000,000  
Gross carrying amount | Senior Notes Due 2049 - 4.350% | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Long-term debt 743,000,000           1,439,000,000  
Gross carrying amount | Senior Notes Due 2049 - 3.700% | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Long-term debt 26,000,000           300,000,000  
Gross carrying amount | Senior Notes Due 2052 - 4.550% | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Long-term debt 2,745,000,000           2,878,000,000  
Gross carrying amount | Senior Notes Due 2052 - 5.250% | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Long-term debt 1,000,000,000           1,000,000,000  
Gross carrying amount | Subordinated Notes Due 2055 - 7.00%, Tranche One | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Long-term debt 1,510,000,000           0  
Gross carrying amount | Subordinated Notes Due 2055 - 7.125%, Tranche Two | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Long-term debt 1,373,000,000           0  
Gross carrying amount | Subordinated Notes Due 2055 - 5.625%, Tranche Three | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Long-term debt 1,000,000,000           0  
Gross carrying amount | Subordinated Notes Due 2081 - 5.000% | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Long-term debt 2,000,000,000           2,000,000,000  
Gross carrying amount | Subordinated Notes Due 2082 - 5.250% | Fixed interest rate                
Disclosure of detailed information about borrowings [line items]                
Long-term debt $ 1,029,000,000           $ 1,079,000,000