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FV Measurements (Classification of Fair Value of Derivatives) (Details) - CAD ($) $ in Millions | Dec. 31, 2024 | Dec. 31, 2023
--- | --- | ---
Assets |  |
Less: Derivatives classified as held for sale | $ (1) | $ 0
Total assets | 166 | 240
Liabilities |  |
Less: Derivatives classified as held for sale | (1) | 0
Total liabilities | 617 | 504
Level 3 |  |
Assets |  |
Total assets | 32 | 34
Liabilities |  |
Total liabilities | 441 | 365
Net assets (liabilities) | (409) | (331)
Level 3 | HFT derivatives | Power swaps and physical contracts |  |
Assets |  |
Total assets | 5 |
Liabilities |  |
Total liabilities | 4 |
Level 3 | HFT derivatives | Natural gas swaps, futures, forwards and physical contracts |  |
Assets |  |
Total assets | 27 | 34
Liabilities |  |
Total liabilities | 437 | 365
Fair Value, Measurements, Recurring |  |
Assets |  |
Less: Derivatives classified as held for sale | (1) |
Total assets | 166 | 240
Liabilities |  |
Less: Derivatives classified as held for sale | (1) |
Total liabilities | 617 | 504
Net assets (liabilities) | (451) | (264)
Fair Value, Measurements, Recurring | Other |  |
Assets |  |
Total assets |  | 22
Liabilities |  |
Total liabilities | 36 | 7
Fair Value, Measurements, Recurring | FX forwards | Other |  |
Assets |  |
Total assets |  | 18
Liabilities |  |
Total liabilities | 34 | 7
Fair Value, Measurements, Recurring | Equity derivatives | Other |  |
Assets |  |
Total assets |  | 4
Liabilities |  |
Less: Derivatives classified as held for sale | (2) |
Fair Value, Measurements, Recurring | Regulatory deferral |  |
Assets |  |
Total assets | 45 | 16
Liabilities |  |
Total liabilities | 40 | 76
Fair Value, Measurements, Recurring | Regulatory deferral | Commodity swaps and forwards |  |
Assets |  |
Total assets | 18 | 13
Liabilities |  |
Total liabilities | 37 | 73
Fair Value, Measurements, Recurring | Regulatory deferral | FX forwards |  |
Assets |  |
Total assets | 27 | 3
Liabilities |  |
Total liabilities | 3 | 3
Fair Value, Measurements, Recurring | HFT derivatives |  |
Assets |  |
Total assets | 122 | 202
Liabilities |  |
Total liabilities | 542 | 421
Fair Value, Measurements, Recurring | HFT derivatives | Power swaps and physical contracts |  |
Assets |  |
Total assets | 30 | 18
Liabilities |  |
Total liabilities | 27 | 24
Fair Value, Measurements, Recurring | HFT derivatives | Natural gas swaps, futures, forwards, physical contracts |  |
Assets |  |
Total assets | 92 | 184
Fair Value, Measurements, Recurring | HFT derivatives | Natural gas swaps, futures, forwards and physical contracts |  |
Liabilities |  |
Total liabilities | 515 | 397
Fair Value, Measurements, Recurring | Level 1 |  |
Assets |  |
Less: Derivatives classified as held for sale | 0 |
Total assets | 30 | 48
Liabilities |  |
Less: Derivatives classified as held for sale | 0 |
Total liabilities | 11 | 56
Net assets (liabilities) | 19 | (8)
Fair Value, Measurements, Recurring | Level 1 | Other |  |
Assets |  |
Total assets |  | 4
Liabilities |  |
Total liabilities | 2 | 0
Fair Value, Measurements, Recurring | Level 1 | FX forwards | Other |  |
Assets |  |
Total assets |  | 0
Liabilities |  |
Total liabilities | 0 | 0
Fair Value, Measurements, Recurring | Level 1 | Equity derivatives | Other |  |
Assets |  |
Total assets |  | 4
Liabilities |  |
Less: Derivatives classified as held for sale | (2) |
Fair Value, Measurements, Recurring | Level 1 | Regulatory deferral |  |
Assets |  |
Total assets | 15 | 7
Liabilities |  |
Total liabilities | 18 | 43
Fair Value, Measurements, Recurring | Level 1 | Regulatory deferral | Commodity swaps and forwards |  |
Assets |  |
Total assets | 15 | 7
Liabilities |  |
Total liabilities | 18 | 43
Fair Value, Measurements, Recurring | Level 1 | Regulatory deferral | FX forwards |  |
Assets |  |
Total assets | 0 | 0
Liabilities |  |
Total liabilities | 0 | 0
Fair Value, Measurements, Recurring | Level 1 | HFT derivatives |  |
Assets |  |
Total assets | 15 | 37
Liabilities |  |
Total liabilities | (9) | 13
Fair Value, Measurements, Recurring | Level 1 | HFT derivatives | Power swaps and physical contracts |  |
Assets |  |
Total assets | 2 | (5)
Liabilities |  |
Total liabilities | 2 | 0
Fair Value, Measurements, Recurring | Level 1 | HFT derivatives | Natural gas swaps, futures, forwards, physical contracts |  |
Assets |  |
Total assets | 13 | 42
Fair Value, Measurements, Recurring | Level 1 | HFT derivatives | Natural gas swaps, futures, forwards and physical contracts |  |
Liabilities |  |
Total liabilities | (11) | 13
Fair Value, Measurements, Recurring | Level 2 |  |
Assets |  |
Less: Derivatives classified as held for sale | (1) |
Total assets | 104 | 158
Liabilities |  |
Less: Derivatives classified as held for sale | (1) |
Total liabilities | 165 | 83
Net assets (liabilities) | (61) | 75
Fair Value, Measurements, Recurring | Level 2 | Other |  |
Assets |  |
Total assets |  | 18
Liabilities |  |
Total liabilities | 34 | 7
Fair Value, Measurements, Recurring | Level 2 | FX forwards | Other |  |
Assets |  |
Total assets |  | 18
Liabilities |  |
Total liabilities | 34 | 7
Fair Value, Measurements, Recurring | Level 2 | Equity derivatives | Other |  |
Assets |  |
Total assets |  | 0
Liabilities |  |
Less: Derivatives classified as held for sale | 0 |
Fair Value, Measurements, Recurring | Level 2 | Regulatory deferral |  |
Assets |  |
Total assets | 30 | 9
Liabilities |  |
Total liabilities | 22 | 33
Fair Value, Measurements, Recurring | Level 2 | Regulatory deferral | Commodity swaps and forwards |  |
Assets |  |
Total assets | 3 | 6
Liabilities |  |
Total liabilities | 19 | 30
Fair Value, Measurements, Recurring | Level 2 | Regulatory deferral | FX forwards |  |
Assets |  |
Total assets | 27 | 3
Liabilities |  |
Total liabilities | 3 | 3
Fair Value, Measurements, Recurring | Level 2 | HFT derivatives |  |
Assets |  |
Total assets | 75 | 131
Liabilities |  |
Total liabilities | 110 | 43
Fair Value, Measurements, Recurring | Level 2 | HFT derivatives | Power swaps and physical contracts |  |
Assets |  |
Total assets | 23 | 23
Liabilities |  |
Total liabilities | 21 | 24
Fair Value, Measurements, Recurring | Level 2 | HFT derivatives | Natural gas swaps, futures, forwards, physical contracts |  |
Assets |  |
Total assets | 52 | 108
Fair Value, Measurements, Recurring | Level 2 | HFT derivatives | Natural gas swaps, futures, forwards and physical contracts |  |
Liabilities |  |
Total liabilities | 89 | 19
Fair Value, Measurements, Recurring | Level 3 |  |
Assets |  |
Less: Derivatives classified as held for sale | 0 |
Total assets | 32 | 34
Liabilities |  |
Less: Derivatives classified as held for sale | 0 |
Total liabilities | 441 | 365
Net assets (liabilities) | (409) | (331)
Fair Value, Measurements, Recurring | Level 3 | Other |  |
Assets |  |
Total assets |  | 0
Liabilities |  |
Total liabilities | 0 | 0
Fair Value, Measurements, Recurring | Level 3 | FX forwards | Other |  |
Assets |  |
Total assets |  | 0
Liabilities |  |
Total liabilities | 0 | 0
Fair Value, Measurements, Recurring | Level 3 | Equity derivatives | Other |  |
Assets |  |
Total assets |  | 0
Liabilities |  |
Less: Derivatives classified as held for sale | 0 |
Fair Value, Measurements, Recurring | Level 3 | Regulatory deferral |  |
Assets |  |
Total assets | 0 | 0
Liabilities |  |
Total liabilities | 0 | 0
Fair Value, Measurements, Recurring | Level 3 | Regulatory deferral | Commodity swaps and forwards |  |
Assets |  |
Total assets | 0 | 0
Liabilities |  |
Total liabilities | 0 | 0
Fair Value, Measurements, Recurring | Level 3 | Regulatory deferral | FX forwards |  |
Assets |  |
Total assets | 0 | 0
Liabilities |  |
Total liabilities | 0 | 0
Fair Value, Measurements, Recurring | Level 3 | HFT derivatives |  |
Assets |  |
Total assets | 32 | 34
Liabilities |  |
Total liabilities | 441 | 365
Fair Value, Measurements, Recurring | Level 3 | HFT derivatives | Power swaps and physical contracts |  |
Assets |  |
Total assets | 5 | 0
Liabilities |  |
Total liabilities | 4 | 0
Fair Value, Measurements, Recurring | Level 3 | HFT derivatives | Natural gas swaps, futures, forwards, physical contracts |  |
Assets |  |
Total assets | 27 | 34
Fair Value, Measurements, Recurring | Level 3 | HFT derivatives | Natural gas swaps, futures, forwards and physical contracts |  |
Liabilities |  |
Total liabilities | $ 437 | $ 365

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