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Employee Defined Benefit Plans - Schedule of Quantitative Sensitivity Analyses Impact on Defined Benefit Obligation for Significant Assumptions (Details) - CAD ($) $ in Millions | Dec. 31, 2024 | Dec. 31, 2023
--- | --- | ---
Change in discount rate by 0.25% |  |
Disclosure of sensitivity analysis for actuarial assumptions [Line Items] |  |
Increase | $ (12.8) | $ (13.8)
Decrease | $ 13.2 | 14.3
Percentage of increase | 0.25% |
Percentage of decrease | 0.25% |
Change in pre-retirement inflation rate by 0.25% |  |
Disclosure of sensitivity analysis for actuarial assumptions [Line Items] |  |
Increase | $ 2.2 | 2.4
Decrease | $ (2.2) | (2.4)
Percentage of increase | 0.25% |
Percentage of decrease | 0.25% |
Change in pension increase assumption by 0.25% |  |
Disclosure of sensitivity analysis for actuarial assumptions [Line Items] |  |
Increase | $ 6.7 | 7.5
Decrease | $ (6.6) | (7.4)
Percentage of increase | 0.25% |
Percentage of decrease | 0.25% |
Change in one year in the life expectancy |  |
Disclosure of sensitivity analysis for actuarial assumptions [Line Items] |  |
Increase | $ 12.0 | 13.5
Decrease | $ (12.0) | $ (13.5)

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- Definition The increase (decrease) in a defined benefit obligation that would have been caused by a decrease in a significant actuarial assumption that was reasonably possible at the end of the reporting period. [Refer: Actuarial assumptions [domain]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2024-01-01 -Paragraph 145 -Subparagraph a -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=19&code=ifrs-tx-2024-en-r&anchor=para_145_a&doctype=Standard -URIDate 2024-03-27 + Details
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- Definition The increase (decrease) in a defined benefit obligation that would have been caused by an increase in a significant actuarial assumption that was reasonably possible at the end of the reporting period. [Refer: Actuarial assumptions [domain]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2024-01-01 -Paragraph 145 -Subparagraph a -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=19&code=ifrs-tx-2024-en-r&anchor=para_145_a&doctype=Standard -URIDate 2024-03-27 + Details
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