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Derivatives Instruments (Derivative Assets and Liabilities) (Details) - CAD ($) $ in Millions | Dec. 31, 2019 | Dec. 31, 2018
--- | --- | ---
Cash flow hedges |  |
Cash flow hedges, Derivative Assets | $ 0 | $ 0
Cash flow hedges, Derivative Liabilities | 1 | 5
HFT derivatives |  |
HFT, Derivative Assets | 170 | 187
HFT, Derivative Liabilities | 403 | 479
Other derivatives |  |
Other, Derivative Assets | 1 | 1
Other, Derivative Liabilities | 0 | 0
Derivative Assets |  |
Total gross current derivative assets | 207 | 293
Impact of master netting agreements with intent to settle net or simultaneously, Derivative Assets | (120) | (126)
Derivative Asset, Total | 87 | 167
Derivative Liabilities |  |
Total gross current derivative liabilities | 490 | 491
Impact of master netting agreements with intent to settle net or simultaneously, Derivative Liabilities | (120) | (126)
Derivative Liabilities, Total | 370 | 365
Foreign exchange forwards |  |
Cash flow hedges |  |
Cash flow hedges, Derivative Assets | 0 | 0
Cash flow hedges, Derivative Liabilities | 1 | 5
Other derivatives |  |
Other, Derivative Assets | 0 | 0
Other, Derivative Liabilities | 0 | 0
Power swaps and physical contracts |  |
HFT derivatives |  |
HFT, Derivative Assets | 19 | 62
HFT, Derivative Liabilities | 22 | 76
Natural gas swaps, futures, forwards, physical contracts |  |
HFT derivatives |  |
HFT, Derivative Assets | 151 | 125
HFT, Derivative Liabilities | 381 | 403
Equity derivatives and interest rate swaps |  |
Other derivatives |  |
Other, Derivative Assets | 1 | 1
Other, Derivative Liabilities | 0 | 0
Regulatory deferral |  |
HFT derivatives |  |
HFT, Derivative Assets | 36 | 105
HFT, Derivative Liabilities | 86 | 7
Derivative Assets |  |
Impact of master netting agreements with intent to settle net or simultaneously, Derivative Assets | (8) | (1)
Derivative Liabilities |  |
Impact of master netting agreements with intent to settle net or simultaneously, Derivative Liabilities | (8) | (1)
Regulatory deferral | Commodity swaps and forwards | Power |  |
HFT derivatives |  |
HFT, Derivative Assets | 23 | 2
HFT, Derivative Liabilities | 36 | 1
Regulatory deferral | Commodity swaps and forwards | Coal |  |
HFT derivatives |  |
HFT, Derivative Assets | 8 | 71
HFT, Derivative Liabilities | 39 | 1
Regulatory deferral | Commodity swaps and forwards | Heavy fuel oil purchases |  |
HFT derivatives |  |
HFT, Derivative Assets | 1 | 1
HFT, Derivative Liabilities | 0 | 1
Regulatory deferral | Commodity swaps and forwards | Natural gas |  |
HFT derivatives |  |
HFT, Derivative Assets | 2 | 2
HFT, Derivative Liabilities | 5 | 4
Regulatory deferral | Foreign exchange forwards |  |
HFT derivatives |  |
HFT, Derivative Assets | 2 | 29
HFT, Derivative Liabilities | 6 | 0
HFT derivatives |  |
Derivative Assets |  |
Impact of master netting agreements with intent to settle net or simultaneously, Derivative Assets | (112) | (125)
Derivative Liabilities |  |
Impact of master netting agreements with intent to settle net or simultaneously, Derivative Liabilities | $ (112) | $ (125)

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