DEBT AND CAPITAL STRUCTURE - Schedule of Net Debt to Adjusted Funds Flow (Details) - CAD ($) $ in Millions |
3 Months Ended | 9 Months Ended | 12 Months Ended | |||
|---|---|---|---|---|---|---|
Sep. 30, 2026 |
Sep. 30, 2025 |
Sep. 30, 2026 |
Sep. 30, 2025 |
Sep. 30, 2026 |
Dec. 31, 2025 |
|
| Borrowings [abstract] | ||||||
| Net Debt | $ 2,999 | $ 2,999 | $ 2,999 | $ 8,292 | ||
| Cash From (Used in) Operating Activities | 5,584 | $ 2,131 | 13,401 | $ 5,820 | 15,809 | 8,228 |
| Settlement of Decommissioning Liabilities | (63) | (94) | (155) | (198) | (237) | (280) |
| Net Change in Non-Cash Working Capital | $ 624 | $ (241) | $ 170 | $ (179) | (52) | (363) |
| Adjusted funds flow | $ 16,098 | $ 8,871 | ||||
| Net Debt to Adjusted Funds Flow (times) | 20.00% | 90.00% | ||||