Employee retirement benefits - Summary of Change in Accumulated Other Comprehensive Income (Detail) - CAD ($) $ in Millions |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2025 |
Dec. 31, 2024 |
Dec. 31, 2023 |
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| Retirement Benefits [Abstract] | |||
| (Charge) credit to other comprehensive income, before-tax | $ 265 | $ 613 | $ (218) |
| Deferred income tax (charge) credit | (65) | (150) | 53 |
| (Charge) credit to other comprehensive income, after-tax | $ 200 | $ 463 | $ (165) |
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- References No definition available.
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- Definition Amount, before tax, after reclassification adjustment, of (increase) decrease in accumulated other comprehensive income for defined benefit plan. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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| X | ||||||||||
- Definition Amount, after tax and reclassification adjustment, of (increase) decrease in accumulated other comprehensive income for defined benefit plan. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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| X | ||||||||||
- Definition Amount, after reclassification adjustment, of tax (expense) benefit for (increase) decrease in accumulated other comprehensive income of defined benefit plan. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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