v3.26.3
SUPPLEMENTARY CASH FLOW INFORMATION - Reconciliation of Liabilities to Cash Flows from Financing Activities (Details) - CAD ($)
$ in Millions
 3 Months Ended 9 Months Ended
Sep. 30, 2026
Sep. 30, 2025
Sep. 30, 2026
Sep. 30, 2025
Disclosure of reconciliation of liabilities arising from financing activities [line items]        
Beginning balance, lease liabilities     $ 3,175  
Changes From Financing Cash Flows:        
Acquisition $ (3) $ (7) (18) $ (236)
Repayment of Long-Term Debt 0 (183) (2,700) (195)
Principal Repayment of Leases (94) (89) (272) (266)
Non-Cash Changes:        
Lease Additions     43  
Modifications     28  
Ending balance, lease liabilities 3,003   3,003  
Dividends Payable        
Disclosure of reconciliation of liabilities arising from financing activities [line items]        
Beginning balance. dividend payables     0 0
Changes From Financing Cash Flows:        
Dividends Paid     (1,193) (1,057)
Non-Cash Changes:        
Ending balance. dividend payables 0 2 0 2
Dividends Payable | Common shares        
Non-Cash Changes:        
Dividends declared     1,191 1,047
Dividends Payable | Preferred Shares        
Non-Cash Changes:        
Dividends declared     2 12
Repurchase Agreements Payable        
Disclosure of reconciliation of liabilities arising from financing activities [line items]        
Beginning balance, Repurchase agreements payable     401 0
Changes From Financing Cash Flows:        
Proceeds on Repurchase Agreements     1,104 403
Repayment of Repurchase Agreements     (1,006) (220)
Non-Cash Changes:        
Exchange Rate Movements and Other     (16) (7)
Ending balance, Repurchase agreements payable 483 176 483 176
Repurchase Agreements Payable - RINs        
Changes From Financing Cash Flows:        
Proceeds on Repurchase Agreements     843  
Repayment of Repurchase Agreements     (745)  
Short-Term Borrowings        
Disclosure of reconciliation of liabilities arising from financing activities [line items]        
Beginning balance, short-term borrowings     0 173
Changes From Financing Cash Flows:        
Net Issuance (Repayment) of Short-Term Borrowings       152
Non-Cash Changes:        
Divestiture of Short-Term Borrowings       (313)
Exchange Rate Movements and Other     0 (12)
Ending balance, short term borrowings 0 0 0 0
Long-Term Debt        
Disclosure of reconciliation of liabilities arising from financing activities [line items]        
Beginning balance, long-term debt     11,032 7,534
Changes From Financing Cash Flows:        
Acquisition       12
Repayment of Long-Term Debt     (2,700) (195)
Non-Cash Changes:        
Finance and Transaction Costs     8 (15)
Exchange Rate Movements and Other     207 (180)
Ending balance, long-term debt 8,547 7,156 8,547 7,156
Lease Liabilities        
Disclosure of reconciliation of liabilities arising from financing activities [line items]        
Beginning balance, lease liabilities     3,175 2,927
Changes From Financing Cash Flows:        
Principal Repayment of Leases     (272) (266)
Non-Cash Changes:        
Lease Additions     43 162
Lease Divestitures     (3) (39)
Exchange Rate Movements and Other     32 88
Ending balance, lease liabilities $ 3,003 $ 2,872 $ 3,003 $ 2,872