Income taxes - Components of Deferred Income Tax Liabilities and Assets (Detail) - CAD ($) $ in Millions |
Dec. 31, 2025 |
Dec. 31, 2024 |
Dec. 31, 2023 |
|---|---|---|---|
| Income Tax Disclosure [Abstract] | |||
| Depreciation and amortization | $ 5,311 | $ 5,267 | $ 5,366 |
| Successful drilling and land acquisitions | 236 | 236 | 237 |
| Pension and benefits | 38 | (15) | (168) |
| Asset retirement obligation | (858) | (686) | (655) |
| Capitalized interest | 202 | 185 | 155 |
| LIFO inventory valuation | (297) | (468) | (406) |
| Tax loss carryforwards | (65) | (66) | (69) |
| Valuation allowance | 65 | 66 | 69 |
| Other | (214) | (35) | (60) |
| Net deferred income tax liabilities | $ 4,418 | $ 4,484 | $ 4,469 |
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- Definition Deferred Tax Assets Inventory Noncurrent No definition available.
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- Definition Deferred Tax Assets Other Non Current No definition available.
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- Definition Deferred Tax Assets, Tax Deferred Expense, Compensation And Benefits, Pension And Benefits, Net No definition available.
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- Definition The tax effect as of the balance sheet date of the amount of the estimated future tax effects arising from successful drilling and land acquisitions expensed for tax purposes, but capitalized for conformity with gaap. No definition available.
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible capital loss carryforwards. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from asset retirement obligations. An asset retirement obligation is a legal obligation associated with the disposal or retirement from service of a tangible long-lived asset. 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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- Definition Amount of deferred tax liability attributable to taxable temporary differences from capitalized interest. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of deferred tax liability attributable to taxable temporary differences from property, plant, and equipment. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- References No definition available.
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