INCOME TAXES - Summary of Deferred Income Tax Assets and Liabilities (Details) - CAD ($) $ in Millions |
Dec. 31, 2025 |
Dec. 31, 2024 |
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| Deferred income tax assets | ||
| Post-retirement and post-employment benefits expense in excess of cash payments | $ 616 | $ 585 |
| Regulatory assets and liabilities | 491 | 449 |
| Non-capital losses | 91 | 105 |
| Non-depreciable capital property | 255 | 255 |
| Tax credit carryforwards | 211 | 245 |
| Investment in subsidiaries | 114 | 113 |
| Capital losses | 27 | 19 |
| Environmental expenditures | 15 | 16 |
| Other | 3 | 11 |
| Deferred income tax assets gross | 1,823 | 1,798 |
| Less: valuation allowance | (399) | (394) |
| Total deferred income tax assets | 1,424 | 1,404 |
| Deferred income tax liabilities | ||
| Capital cost allowance in excess of depreciation and amortization | 2,874 | 2,494 |
| Pension assets | 214 | 235 |
| Total deferred income tax liabilities | 3,088 | 2,729 |
| Net deferred income tax liabilities | $ (1,664) | $ (1,325) |
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- Definition Deferred Tax Asset, Regulatory Assets and Liabilities No definition available.
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- Definition Deferred Tax Assets, Capital Losses No definition available.
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- Definition Deferred Tax Assets Environmental Reserve No definition available.
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- Definition Deferred tax assets non capital losses. No definition available.
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- Definition Deferred tax assets non depreciable capital property. No definition available.
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- Definition Deferred Tax Assets Post Retirement And Post Employment Benefit Expense In Excess Of Cash Payments No definition available.
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- Definition Deferred Tax Liabilities Capital Cost Allowance In Excess Of Depreciation And Amortization No definition available.
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- Definition Deferred Tax Liabilities, Pension Assets No definition available.
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- Definition Amount of deferred tax liability attributable to taxable temporary differences. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- References No definition available.
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from the entity's investment in its wholly-owned subsidiaries. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount, before allocation of valuation allowance, of deferred tax asset attributable to deductible temporary differences, classified as other. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount, before allocation of a valuation allowances, of deferred tax assets attributable to deductible tax credit carryforwards including, but not limited to, research, foreign, general business, alternative minimum tax, and other deductible tax credit carryforwards. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount, after deferred tax asset, of deferred tax liability attributable to taxable differences without jurisdictional netting. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- References No definition available.
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