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Risk Management Activities - Net Risk Management Assets and Liabilities (Details) - CAD ($) $ in Millions | Dec. 31, 2024 | Dec. 31, 2023
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Financial Liabilities |  |
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |
Commodity risk management assets and liabilities | $ (171) | $ (385)
Commodity risk management | Current risk management liabilities |  |
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |
Commodity risk management assets and liabilities | 53 | (178)
Commodity risk management | Long-term risk management liabilities |  |
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |
Commodity risk management assets and liabilities | (220) | (226)
Commodity risk management | Financial Liabilities |  |
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |
Commodity risk management assets and liabilities | (167) | (404)
Other | Current risk management liabilities |  |
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |
Commodity risk management assets and liabilities |  | 15
Other | Long-term risk management liabilities |  |
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |
Commodity risk management assets and liabilities |  | 4
Other | Financial Liabilities |  |
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |
Commodity risk management assets and liabilities |  | 19
Current | Other |  |
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |
Commodity risk management assets and liabilities | (12) |
Long-term | Other |  |
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |
Commodity risk management assets and liabilities | 8 |
Financial Assets | Other |  |
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |
Commodity risk management assets and liabilities | (4) |
Cash flow hedges | Cash flow hedges | Financial Liabilities |  |
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |
Commodity risk management assets and liabilities | 45 | (205)
Cash flow hedges | Cash flow hedges | Commodity risk management | Current risk management liabilities |  |
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |
Commodity risk management assets and liabilities | 45 | (125)
Cash flow hedges | Cash flow hedges | Commodity risk management | Long-term risk management liabilities |  |
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |
Commodity risk management assets and liabilities | 0 | (80)
Cash flow hedges | Cash flow hedges | Commodity risk management | Financial Liabilities |  |
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |
Commodity risk management assets and liabilities | 45 | (205)
Cash flow hedges | Cash flow hedges | Other | Current risk management liabilities |  |
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |
Commodity risk management assets and liabilities |  | 0
Cash flow hedges | Cash flow hedges | Other | Long-term risk management liabilities |  |
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |
Commodity risk management assets and liabilities |  | 0
Cash flow hedges | Cash flow hedges | Other | Financial Liabilities |  |
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |
Commodity risk management assets and liabilities |  | 0
Cash flow hedges | Current | Cash flow hedges | Other |  |
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |
Commodity risk management assets and liabilities | 0 |
Cash flow hedges | Long-term | Cash flow hedges | Other |  |
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |
Commodity risk management assets and liabilities | 0 |
Cash flow hedges | Financial Assets | Cash flow hedges | Other |  |
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |
Commodity risk management assets and liabilities | 0 |
Not designated as a hedge | Financial Liabilities |  |
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |
Commodity risk management assets and liabilities | (216) | (180)
Not designated as a hedge | Commodity risk management | Current risk management liabilities |  |
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |
Commodity risk management assets and liabilities | 8 | (53)
Not designated as a hedge | Commodity risk management | Long-term risk management liabilities |  |
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |
Commodity risk management assets and liabilities | (220) | (146)
Not designated as a hedge | Commodity risk management | Financial Liabilities |  |
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |
Commodity risk management assets and liabilities | (212) | (199)
Not designated as a hedge | Other | Current risk management liabilities |  |
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |
Commodity risk management assets and liabilities |  | 15
Not designated as a hedge | Other | Long-term risk management liabilities |  |
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |
Commodity risk management assets and liabilities |  | 4
Not designated as a hedge | Other | Financial Liabilities |  |
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |
Commodity risk management assets and liabilities |  | $ 19
Not designated as a hedge | Current | Other |  |
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |
Commodity risk management assets and liabilities | (12) |
Not designated as a hedge | Long-term | Other |  |
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |
Commodity risk management assets and liabilities | 8 |
Not designated as a hedge | Financial Assets | Other |  |
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |
Commodity risk management assets and liabilities | $ (4) |

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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 amount of risk exposure associated with financial instruments with a shared characteristic that identifies a concentration of risks. [Refer: Classes of financial instruments [domain]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 7 -IssueDate 2024-01-01 -Paragraph B8 -Subparagraph c -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2024-en-r&anchor=para_B8_c&doctype=Appendix&subtype=B -URIDate 2024-03-27 + Details
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