Interest expense (Details) - CAD ($) $ in Millions |
12 Months Ended | |
|---|---|---|
Dec. 31, 2025 |
Dec. 31, 2024 |
|
| Disclosure of detailed information about borrowings [line items] | ||
| Capitalized interest | $ 122 | $ 143 |
| Interest expense | $ (1,775) | $ (1,713) |
| Capitalisation rate of borrowing costs eligible for capitalisation | 4.60% | 4.50% |
| Interest expense on long-term debt | ||
| Disclosure of detailed information about borrowings [line items] | ||
| Total interest expense | $ (1,718) | $ (1,623) |
| Interest expense on other debt | ||
| Disclosure of detailed information about borrowings [line items] | ||
| Total interest expense | (179) | (233) |
| Lease liabilities | ||
| Disclosure of detailed information about borrowings [line items] | ||
| Total interest expense | $ (194) | $ (218) |