Financing costs (Detail) - CAD ($) $ in Millions |
3 Months Ended | 6 Months Ended | |||||||||||||||||||||||||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Jun. 30, 2026 |
Jun. 30, 2025 |
Jun. 30, 2026 |
Jun. 30, 2025 |
||||||||||||||||||||||||||||||||||||||||||||||||
| Financing costs and additional notes and loans payable information [Abstract] | |||||||||||||||||||||||||||||||||||||||||||||||||||
| Debt-related interest | $ 33 | $ 27 | $ 64 | $ 64 | |||||||||||||||||||||||||||||||||||||||||||||||
| Capitalized interest | (23) | (25) | (44) | (52) | |||||||||||||||||||||||||||||||||||||||||||||||
| Net interest expense | 10 | 2 | 20 | 12 | |||||||||||||||||||||||||||||||||||||||||||||||
| Other interest | 4 | 0 | 5 | (12) | |||||||||||||||||||||||||||||||||||||||||||||||
| Total financing | [1] | $ 14 | $ 2 | $ 25 | $ 0 | ||||||||||||||||||||||||||||||||||||||||||||||
| |||||||||||||||||||||||||||||||||||||||||||||||||||
| X | ||||||||||
- Definition Financing costs and additional notes and loans payable information No definition available.
|
| X | ||||||||||
- Definition Amount of the cost of borrowed funds accounted for as interest expense. No definition available.
|
| X | ||||||||||
- Definition Interest and debt related expenses associated with nonoperating financing activities of the entity. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
|
| X | ||||||||||
- Definition Amount of interest expense classified as operating and nonoperating. Includes, but is not limited to, cost of borrowing accounted for as interest expense. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
|
| X | ||||||||||
- Definition Amount of the cost of borrowed funds accounted for as interest expense for debt. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition Amount of cash paid for interest capitalized, classified as investing activity. Reference 1: http://www.xbrl.org/2003/role/exampleRef
|