Other comprehensive income (loss) information - Changes in Accumulated Other Comprehensive Income (Loss) (Detail) - CAD ($) $ in Millions |
12 Months Ended | ||
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Dec. 31, 2025 |
Dec. 31, 2024 |
Dec. 31, 2023 |
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| AOCI Attributable to Parent, Net of Tax [Roll Forward] | |||
| At beginning of period | $ 23,473 | $ 22,222 | |
| At end of period | 22,254 | 23,473 | $ 22,222 |
| Accumulated Defined Benefit Plans Adjustment Attributable to Parent | |||
| AOCI Attributable to Parent, Net of Tax [Roll Forward] | |||
| At beginning of period | (214) | (677) | (512) |
| Current period change excluding amounts reclassified from accumulated other comprehensive income | 181 | 412 | (206) |
| Amounts reclassified from accumulated other comprehensive income | 19 | 51 | 41 |
| At end of period | $ (14) | $ (214) | $ (677) |
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. No definition available.
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- Definition Amount after tax, before reclassification adjustments, of other comprehensive income (loss), attributable to parent. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount after tax of reclassification adjustments of other comprehensive income (loss) attributable to parent. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of equity (deficit) attributable to parent. Excludes temporary equity and equity attributable to noncontrolling interest. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Details
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