Employee retirement benefits - Plan Assets (Detail) - CAD ($) $ in Millions |
12 Months Ended | |
|---|---|---|
Dec. 31, 2025 |
Dec. 31, 2024 |
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| Change in plan assets | ||
| Fair value at January 1 | $ 8,553 | |
| Fair value at December 31 | 8,582 | $ 8,553 |
| Pension benefits | ||
| Change in plan assets | ||
| Fair value at January 1 | 8,553 | 8,054 |
| Actual return (loss) gain | 345 | 805 |
| Company contributions | 148 | 150 |
| Benefits paid | (459) | (452) |
| Other | (5) | (4) |
| Fair value at December 31 | 8,582 | 8,553 |
| Total | 626 | 422 |
| Pension benefits | Funded plans | ||
| Change in plan assets | ||
| Total | 1,035 | 853 |
| Pension benefits | Unfunded plans | ||
| Change in plan assets | ||
| Total | (409) | (431) |
| Other postretirement benefits | ||
| Change in plan assets | ||
| Total | (465) | (476) |
| Other postretirement benefits | Unfunded plans | ||
| Change in plan assets | ||
| Total | $ (465) | $ (476) |
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- Definition Defined Benefit Plan, Plan Asset, Other No definition available.
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- Definition Amount of increase (decrease) in plan assets of defined benefit plan from actual return (loss) determined by change in fair value of plan assets adjusted for contributions, benefit payments, and other expenses. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. No definition available.
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- Definition Amount of contribution received by defined benefit plan from employer which increases plan assets. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of asset segregated and restricted to provide benefit under defined benefit plan. Asset includes, but is not limited to, stock, bond, other investment, earning from investment, and contribution by employer and employee. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of funded (unfunded) status of defined benefit plan, measured as difference between fair value of plan assets and benefit obligation. Includes, but is not limited to, overfunded (underfunded) status. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of payment to participant under defined benefit plan which decreases plan assets. For pension plan, payment includes, but is not limited to, pension benefits and death benefits. For other postretirement plan, payment includes, but is not limited to, prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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