Financing costs (Detail) - CAD ($) $ in Millions |
3 Months Ended | ||||||||||||||||||||||||||||||||||||||||||||||||
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Mar. 31, 2026 |
Mar. 31, 2025 |
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| Financing costs and additional notes and loans payable information [Abstract] | |||||||||||||||||||||||||||||||||||||||||||||||||
| Debt-related interest | $ 31 | $ 37 | |||||||||||||||||||||||||||||||||||||||||||||||
| Capitalized interest | (21) | (27) | |||||||||||||||||||||||||||||||||||||||||||||||
| Net interest expense | 10 | 10 | |||||||||||||||||||||||||||||||||||||||||||||||
| Other interest | 1 | (12) | |||||||||||||||||||||||||||||||||||||||||||||||
| Total financing | [1] | $ 11 | $ (2) | ||||||||||||||||||||||||||||||||||||||||||||||
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| X | ||||||||||
- Definition Financing costs and additional notes and loans payable information No definition available.
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- Definition Amount of the cost of borrowed funds accounted for as interest expense. No definition available.
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| X | ||||||||||
- Definition Interest and debt related expenses associated with nonoperating financing activities of the entity. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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| 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
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- 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
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- Definition Amount of cash paid for interest capitalized, classified as investing activity. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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