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Defined Benefit Obligation and Other Long-Term Liabilities - Narrative (Details) $ in Millions, $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2024 CAD ($) | Dec. 31, 2023 CAD ($) | Dec. 31, 2023 USD ($) | Jun. 30, 2024 CAD ($) | Jun. 30, 2024 USD ($)
Disclosure of fair value measurement of liabilities [line items] |  |  |  |  |
Increase (decrease) in defined benefit obligation | $ (9) |  |  |  |
Defined benefit obligation | 146 | $ 155 |  |  |
Plan assets | 257 | 284 |  | $ 23 | $ 17
Voluntary contribution | $ 0 | $ 4 | $ 3 |  |
Increase in discount rates | 100.00% |  |  |  |
Pro Forma |  |  |  |  |
Disclosure of fair value measurement of liabilities [line items] |  |  |  |  |
Increase (decrease) in defined benefit obligation | $ 34 |  |  |  |

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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. + References No definition available. + Details
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- Definition The increase (decrease) in the net defined benefit liability (asset). [Refer: Net defined benefit liability (asset)] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2024-01-01 -Paragraph 141 -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=19&code=ifrs-tx-2024-en-r&anchor=para_141&doctype=Standard -URIDate 2024-03-27 + Details
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- Definition The amount of non-current net defined benefit liability. [Refer: Net defined benefit liability] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 1 -IssueDate 2024-01-01 -Paragraph 55 -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2024-en-r&anchor=para_55&doctype=Standard -URIDate 2024-03-27 + Details
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- Definition The fair value of defined benefit plan assets. Plan assets comprise assets held by a long-term employee benefit fund and qualifying insurance policies. [Refer: At fair value [member]] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 19 -IssueDate 2024-01-01 -Paragraph 57 -Subparagraph a -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=19&code=ifrs-tx-2024-en-r&anchor=para_57_a&doctype=Standard -URIDate 2024-03-27 + Details
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- Definition Increase in Discount Rates + References No definition available. + Details
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- Definition Voluntary Contribution + References No definition available. + Details
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- Details
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