Income taxes - Summary of Income Taxes (Detail) - CAD ($) $ in Millions |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2025 |
Dec. 31, 2024 |
Dec. 31, 2023 |
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| Income Tax Disclosure [Abstract] | |||
| Current income tax expense (benefit) | $ 1,125 | $ 1,586 | $ 1,556 |
| Deferred income tax expense (benefit) | (131) | (137) | (76) |
| Total income tax expense (benefit) | 994 | 1,449 | 1,480 |
| Federal | 625 | 902 | 920 |
| Provincial | 369 | 547 | 560 |
| Income (loss) before income taxes | 4,262 | 6,239 | 6,369 |
| Canadian federal statutory tax rate | $ 639 | $ 935 | $ 955 |
| Canadian federal statutory tax rate (percent) | 15.00% | 15.00% | 15.00% |
| Provincial | $ 376 | $ 567 | $ 582 |
| Provincial (percent) | 8.80% | 9.10% | 9.10% |
| Other adjustments | $ (21) | $ (53) | $ (57) |
| Other adjustments (percent) | (0.50%) | (0.90%) | (0.90%) |
| Effective income tax rate | 23.30% | 23.20% | 23.20% |
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- Definition Amount of current income tax expense (benefit) pertaining to taxable income (loss) from continuing operations. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of deferred income tax expense (benefit) pertaining to income (loss) from continuing operations. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Percentage of domestic federal statutory tax rate applicable to pretax income (loss). Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to other adjustments. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations applicable to state and local income tax expense (benefit), net of federal tax expense (benefit). Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of current and deferred federal tax expense (benefit) attributable to income (loss) from continuing operations. Includes, but is not limited to, current and deferred national tax expense (benefit) for non-US (United States of America) jurisdiction. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- References No definition available.
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| X | ||||||||||
- Definition Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from continuing operations. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to other adjustments. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to state and local income tax expense (benefit). Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of current and deferred state and local tax expense (benefit) attributable to income (loss) from continuing operations. Includes, but is not limited to, current and deferred regional, territorial, and provincial tax expense (benefit) for non-US (United States of America) jurisdiction. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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