Long-term debt - Narrative (Details) - CAD ($) |
Oct. 30, 2025 |
Sep. 30, 2025 |
Sep. 30, 2024 |
|---|---|---|---|
| Disclosure of detailed information about borrowings [line items] | |||
| Borrowings | $ 3,637,835,000 | $ 2,688,308,000 | |
| Unsecured committed revolving credit facility | |||
| Disclosure of detailed information about borrowings [line items] | |||
| Borrowings, capacity of unsecured credit facility | 1,500,000,000 | ||
| Borrowings | 0 | ||
| Collateral amount against facility to cover letters of credits | $ 3,752,000 | ||
| Unsecured committed revolving credit facility | Extension of uncommitted RCF | |||
| Disclosure of detailed information about borrowings [line items] | |||
| Borrowings, extension period | 1 year |