PENSION PLANS AND POSTRETIREMENT BENEFITS - Changes in the plans benefit obligations (Details) - Present value of defined benefit - CAD ($) $ in Millions |
12 Months Ended | |
|---|---|---|
Dec. 31, 2025 |
Dec. 31, 2024 |
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| Pension and postretirement benefits | ||
| Disclosure of net defined benefit liability (asset) | ||
| Benefit obligations at the beginning of the year | $ 560.8 | $ 538.1 |
| Service costs | 14.1 | 14.6 |
| Interest costs | 24.1 | 25.5 |
| Plan participants' contributions | 4.7 | 5.1 |
| Actuarial (gain) loss arising from: | ||
| Financial assumptions | (19.9) | (5.0) |
| Demographic assumptions | (2.9) | |
| Participant experience | (3.6) | 1.0 |
| Benefits and settlements paid | (18.1) | (18.3) |
| Plan amendments and other | (0.2) | |
| Benefit obligations at the end of the year | 559.2 | 560.8 |
| Postretirement defined benefit plans | ||
| Disclosure of net defined benefit liability (asset) | ||
| Benefit obligations at the beginning of the year | 19.3 | 19.0 |
| Actuarial (gain) loss arising from: | ||
| Benefit obligations at the end of the year | $ 16.8 | $ 19.3 |
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- Definition The decrease (increase) in a net defined benefit liability (asset) resulting from actuarial gains (losses) arising from changes in demographic assumptions that result in remeasurements of the net defined benefit liability (asset). Demographic assumptions deal with matters such as: (a) mortality; (b) rates of employee turnover, disability and early retirement; (c) the proportion of plan members with dependants who will be eligible for benefits; (d) the proportion of plan members who will select each form of payment option available under the plan terms; and (e) claim rates under medical plans. [Refer: Net defined benefit liability (asset)] Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The decrease (increase) in a net defined benefit liability (asset) resulting from actuarial gains (losses) arising from changes in financial assumptions that result in remeasurements of the net defined benefit liability (asset). Financial assumptions deal with items such as: (a) the discount rate; (b) benefit levels, excluding any cost of the benefits to be met by employees, and future salary; (c) in the case of medical benefits, future medical costs, including claim handling costs (ie the costs that will be incurred in processing and resolving claims, including legal and adjuster's fees); and (d) taxes payable by the plan on contributions relating to service before the reporting date or on benefits resulting from that service. [Refer: Net defined benefit liability (asset)] Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The decrease (increase) in a net defined benefit liability (asset) resulting from actuarial gains (losses) arising from experience adjustments that result in remeasurements of the net defined benefit liability (asset). Experience adjustments deal with the effects of differences between the previous actuarial assumptions and what has actually occurred. [Refer: Net defined benefit liability (asset)] Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition The decrease (increase) in the net defined benefit liability (asset) resulting from contributions to a defined benefit plan by plan participants. [Refer: Net defined benefit liability (asset); Defined benefit plans [domain]] Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The increase (decrease) in the net defined benefit liability (asset) resulting from employee service in the current period. [Refer: Net defined benefit liability (asset)] Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with members defined in one or many axes of the table. No definition available.
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- References No definition available.
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- Definition The increase (decrease) in the net defined benefit liability (asset) resulting from changes that the entity does not separately disclose in the same statement or note. [Refer: Net defined benefit liability (asset)] Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- References Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The amount of deficit or surplus in a defined benefit plan, adjusted for any effect of limiting a net defined benefit asset to the asset ceiling. [Refer: Defined benefit plans [domain]] Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The decrease (increase) in the net defined benefit liability (asset) resulting from payments from the plan for benefits and settlements. No definition available.
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