Fair Value of Financial Instruments and Risk Management - Schedule of Derivative Offset Netting (Details) - Energy contracts - CAD ($) $ in Millions |
Jun. 30, 2026 |
Dec. 31, 2025 |
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| Derivative assets | ||
| Gross Amount Recognized in Balance Sheet | $ 61 | $ 55 |
| Counterparty Netting of Energy Contracts | (26) | (29) |
| Posted/Received | 12 | 15 |
| Net Amount | 47 | 41 |
| Derivative liabilities | ||
| Gross Amount Recognized in Balance Sheet | (158) | (151) |
| Counterparty Netting of Energy Contracts | 26 | 29 |
| Cash Collateral Posted/(Received) | 0 | 0 |
| Net Amount | $ (132) | $ (122) |
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- Definition Derivative Asset, Subject to Master Netting Arrangement, Collateral, Obligation to Return (Receive) Cash, Offset Against Derivative Asset No definition available.
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- Definition Fair value of liability associated with financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Fair value of financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and contract can be net settled by means outside contract or delivery of asset, subject to master netting arrangement or similar agreement and not elected or qualified to offset, deducted from derivative asset. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- References No definition available.
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- Definition Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Fair value, after effect of master netting arrangement and deduction of obligation to return financial collateral not offset and financial instrument subject to master netting arrangement not offset, of financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and contract can be net settled by means outside contract or delivery of asset. Includes derivative not subject to master netting arrangement or similar agreement. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Fair value, after effect of master netting arrangement and deduction of obligation to return financial collateral not offset and financial instrument subject to master netting arrangement not offset, of financial liability or contract with one or more underlyings, notional amount or payment provision or both, and contract can be net settled by means outside contract or delivery of asset. Includes derivative not subject to master netting arrangement or similar agreement. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- References No definition available.
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- Definition Amount of right to receive cash collateral under master netting arrangements offset against derivative liabilities. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Fair value of financial liability or contract with one or more underlyings, notional amount or payment provision or both, and contract can be net settled by means outside contract or delivery of asset, subject to master netting arrangement or similar agreement and not elected or qualified to offset, deducted from derivative liability. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Details
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