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Derivatives Instruments (Derivative Assets and Liabilities) (Details) - CAD ($) $ in Millions | Dec. 31, 2020 | Dec. 31, 2019
--- | --- | ---
Cash flow hedges |  |
Cash flow hedges, Derivative Assets | $ 1 | $ 0
Cash flow hedges, Derivative Liabilities | 0 | 1
HFT derivatives |  |
Derivative Assets | 152 | 170
Derivative Liabilities | 359 | 403
Other derivatives |  |
Other, Derivative Assets | 15 | 1
Other, Derivative Liabilities | 1 | 0
Derivative Assets |  |
Total gross current derivative assets | 184 | 207
Impact of master netting agreements with intent to settle net or simultaneously, Derivative Assets | (86) | (120)
Derivative Asset, Total | 98 | 87
Derivative Liabilities |  |
Total gross current derivative liabilities | 424 | 490
Impact of master netting agreements with intent to settle net or simultaneously, Derivative Liabilities | (86) | (120)
Derivative Liabilities, Total | 338 | 370
Equity derivatives |  |
Other derivatives |  |
Other, Derivative Assets | 0 | 1
Other, Derivative Liabilities | 1 | 0
Foreign exchange forwards |  |
Cash flow hedges |  |
Cash flow hedges, Derivative Assets | 0 | 0
Cash flow hedges, Derivative Liabilities | 0 | 1
Other derivatives |  |
Other, Derivative Assets | 15 | 0
Other, Derivative Liabilities | 0 | 0
Power swaps and physical contracts |  |
HFT derivatives |  |
Derivative Assets | 13 | 19
Derivative Liabilities | 13 | 22
Natural gas swaps, futures, forwards, physical contracts and related transportation |  |
HFT derivatives |  |
Derivative Assets | 139 | 151
Derivative Liabilities | 346 | 381
Regulatory deferral |  |
HFT derivatives |  |
Derivative Assets | 16 | 36
Derivative Liabilities | 64 | 86
Derivative Assets |  |
Impact of master netting agreements with intent to settle net or simultaneously, Derivative Assets | (2) | (8)
Derivative Liabilities |  |
Impact of master netting agreements with intent to settle net or simultaneously, Derivative Liabilities | (2) | (8)
Regulatory deferral | Commodity swaps and forwards | Power |  |
HFT derivatives |  |
Derivative Assets | 10 | 23
Derivative Liabilities | 34 | 36
Regulatory deferral | Commodity swaps and forwards | Coal |  |
HFT derivatives |  |
Derivative Assets | 1 | 8
Derivative Liabilities | 6 | 39
Regulatory deferral | Commodity swaps and forwards | Heavy fuel oil purchases |  |
HFT derivatives |  |
Derivative Assets | 1 | 1
Derivative Liabilities | 5 | 0
Regulatory deferral | Commodity swaps and forwards | Natural gas |  |
HFT derivatives |  |
Derivative Assets | 4 | 2
Derivative Liabilities | 2 | 5
Regulatory deferral | Foreign exchange forwards |  |
HFT derivatives |  |
Derivative Assets | 0 | 2
Derivative Liabilities | 17 | 6
HFT derivatives |  |
Derivative Assets |  |
Impact of master netting agreements with intent to settle net or simultaneously, Derivative Assets | (84) | (112)
Derivative Liabilities |  |
Impact of master netting agreements with intent to settle net or simultaneously, Derivative Liabilities | $ (84) | $ (112)

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