Contract costs (Details) - CAD ($) $ in Thousands |
Sep. 30, 2025 |
Sep. 30, 2024 |
|---|---|---|
| Disclosure Of Contract Costs [Line Items] | ||
| Transition costs | $ 366,449 | $ 336,728 |
| Incentives | 4,483 | 7,301 |
| Contract assets | 370,932 | 344,029 |
| Cost | ||
| Disclosure Of Contract Costs [Line Items] | ||
| Transition costs | 690,012 | 610,971 |
| Incentives | 18,757 | 51,045 |
| Contract assets | 708,769 | 662,016 |
| Accumulated amortization and impairment | ||
| Disclosure Of Contract Costs [Line Items] | ||
| Transition costs | 323,563 | 274,243 |
| Incentives | 14,274 | 43,744 |
| Contract assets | $ 337,837 | $ 317,987 |