Employee Future Benefits - Schedule of Net Benefit Costs (Details) - CAD ($) $ in Millions |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Jun. 30, 2026 |
Jun. 30, 2025 |
Jun. 30, 2026 |
Jun. 30, 2025 |
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| Defined Benefit Pension Plans | ||||
| Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract] | ||||
| Service costs | $ 18 | $ 18 | $ 36 | $ 36 |
| Interest costs | 44 | 43 | 88 | 86 |
| Expected return on plan assets | (57) | (53) | (114) | (107) |
| Amortization of actuarial gains | (6) | (4) | (13) | (8) |
| Amortization of past service credits/plan amendments | 2 | 0 | 3 | 0 |
| Regulatory adjustments | (1) | 0 | (1) | (1) |
| Net benefit cost | 0 | 4 | (1) | 6 |
| OPEB Plans | ||||
| Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract] | ||||
| Service costs | 6 | 5 | 11 | 11 |
| Interest costs | 7 | 7 | 15 | 15 |
| Expected return on plan assets | (7) | (7) | (15) | (14) |
| Amortization of actuarial gains | (7) | (6) | (13) | (12) |
| Amortization of past service credits/plan amendments | 0 | 0 | 0 | 0 |
| Regulatory adjustments | 0 | 2 | 0 | 4 |
| Net benefit cost | $ (1) | $ 1 | $ (2) | $ 4 |
| X | ||||||||||
- Definition Defined Benefit Plan, Regulatory Adjustments No definition available.
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- Definition Amount of gain (loss) recognized in net periodic benefit (cost) credit of defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of prior service cost (credit) recognized in net periodic benefit cost (credit) of defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of expected return (loss) recognized in net periodic benefit (cost) credit, calculated based on expected long-term rate of return and market-related value of plan assets of defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of cost recognized for passage of time related to defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of net periodic benefit cost (credit) for defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- References No definition available.
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- Definition Amount of cost for actuarial present value of benefits attributed to service rendered by employee for defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Details
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- Details
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