Intangible Assets - Schedule of Intangible Assets (Details) - CAD ($) $ in Millions |
Dec. 31, 2024 |
Dec. 31, 2023 |
|---|---|---|
| Finite-Lived and Indefinite Lived Intangible Assets [Line Items] | ||
| Cost | $ 2,459 | $ 2,301 |
| Accumulated Amortization | (798) | (791) |
| Net Book Value | 1,661 | 1,510 |
| Land, transmission and water rights | ||
| Finite-Lived and Indefinite Lived Intangible Assets [Line Items] | ||
| Cost | 1,188 | 1,071 |
| Accumulated Amortization | (210) | (182) |
| Net Book Value | 978 | 889 |
| Assets under construction | ||
| Finite-Lived and Indefinite Lived Intangible Assets [Line Items] | ||
| Cost | 93 | 58 |
| Accumulated Amortization | 0 | 0 |
| Net Book Value | 93 | 58 |
| Computer software | ||
| Finite-Lived and Indefinite Lived Intangible Assets [Line Items] | ||
| Cost | 1,035 | 1,040 |
| Accumulated Amortization | (493) | (528) |
| Net Book Value | 542 | 512 |
| Other | ||
| Finite-Lived and Indefinite Lived Intangible Assets [Line Items] | ||
| Cost | 143 | 132 |
| Accumulated Amortization | (95) | (81) |
| Net Book Value | $ 48 | $ 51 |