Employee retirement benefits - Narrative (Detail) - CAD ($) $ in Millions |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2025 |
Dec. 31, 2024 |
Dec. 31, 2023 |
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| Defined Benefit Plan Disclosure [Line Items] | |||
| Health care cost trend rate assumed for 2026 | 6.14% | ||
| Health care cost trend rate assumed for 2040 and beyond | 3.57% | ||
| Long-term expected return | 4.40% | ||
| Actual rate of return over the last 10 years | 4.50% | ||
| Actual rate of return over the last 20 years | 5.60% | ||
| Cost for defined contributions plans | $ 47 | $ 47 | $ 44 |
| Cash contributions to pension plans in 2026 | $ 151 | ||
| Defined Benefit Plan, Equity Securities | |||
| Defined Benefit Plan Disclosure [Line Items] | |||
| Target allocation securities | 15.00% | ||
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- Definition Actual rate of return over the last 10 years. No definition available.
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- Definition Actual rate of return over the last 20 years. No definition available.
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- Definition Defined benefit plan health care cost trend rate assumed later than next fiscal year. No definition available.
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- Definition Weighted average rate of return on plan assets, reflecting average rate of earnings expected on existing plan assets and expected contributions, used to determine net periodic benefit cost of defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of contribution expected to be received by defined benefit plan from employer in next fiscal year following current fiscal year. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Assumed rate, for next fiscal year, based on annual change in cost of health care cost benefits used to measure expected cost of benefits covered by defined benefit postretirement plan. Factors include, but are not limited to, estimate of health care inflation, change in health care utilization or delivery pattern, technological advances, and change in health status of participant. Excludes factors for change in composition of plan population by age and dependency status. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Percentage of target investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of cost for defined contribution plan. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Details
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