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Defined Benefit Obligation and Other Long-Term Liabilities - Narrative (Details) - CAD ($) $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2022 | Dec. 31, 2021
Disclosure of fair value measurement of liabilities [line items] |  |
Increase (decrease) in defined benefit obligation | $ (78) |
Defined benefit obligation | 150 | $ 228
Voluntary contribution | $ 35 |
Increase in discount rates | 1.00% |
Pro Forma |  |
Disclosure of fair value measurement of liabilities [line items] |  |
Increase (decrease) in defined benefit obligation | $ 39 |
Level II | Recurring fair value measurement |  |
Disclosure of fair value measurement of liabilities [line items] |  |
Commodity risk management assets and liabilities | 173 | $ 122
Level II | Recurring fair value measurement | retail power contract liabilities |  |
Disclosure of fair value measurement of liabilities [line items] |  |
Commodity risk management assets and liabilities | 129 |
Risk management assets | Level II | Recurring fair value measurement |  |
Disclosure of fair value measurement of liabilities [line items] |  |
Commodity risk management assets and liabilities | $ 139 |

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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 2022-03-24 -Paragraph 141 -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=19&code=ifrs-tx-2022-en-r&anchor=para_141&doctype=Standard -URIDate 2022-03-24 + Details
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- Definition The amount of risk exposure associated with financial instruments with a shared characteristic that identifies a concentration of risks. [Refer: Financial instruments, class [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 7 -IssueDate 2022-03-24 -Paragraph B8 -Subparagraph c -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2022-en-r&anchor=para_B8_c&doctype=Appendix&subtype=B -URIDate 2022-03-24 + Details
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