Financing costs (Detail) - CAD ($) $ in Millions |
3 Months Ended | 9 Months Ended | |||||||||||||||||||||||||||||||||||||||||||||||||
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Sep. 30, 2026 |
Sep. 30, 2025 |
Sep. 30, 2026 |
Sep. 30, 2025 |
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| Financing costs and additional notes and loans payable information [Abstract] | |||||||||||||||||||||||||||||||||||||||||||||||||||
| Debt-related interest | $ 32 | $ 39 | $ 96 | $ 103 | |||||||||||||||||||||||||||||||||||||||||||||||
| Capitalized interest | (24) | (34) | (68) | (86) | |||||||||||||||||||||||||||||||||||||||||||||||
| Net interest expense | 8 | 5 | 28 | 17 | |||||||||||||||||||||||||||||||||||||||||||||||
| Other interest | 5 | 3 | 10 | (9) | |||||||||||||||||||||||||||||||||||||||||||||||
| Total financing | [1] | $ 13 | $ 8 | $ 38 | $ 8 | ||||||||||||||||||||||||||||||||||||||||||||||
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- 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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- 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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- 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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