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v3.19.3.a.u2

Risk Management Activities - Non-Hedges (Details) $ in Millions, kJ in Billions | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2019 CAD ($) MWh | Dec. 31, 2018 CAD ($) MWh | Dec. 31, 2017 CAD ($) | Dec. 31, 2019 kJ | Dec. 31, 2019 t | Dec. 31, 2019 J | Dec. 31, 2019 MW | Dec. 31, 2018 kJ | Dec. 31, 2018 t | Dec. 31, 2018 J | Dec. 31, 2018 MW
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |  |  |  |  |  |  |  |  |  |
Gains (losses) on change in fair value of derivatives | $ | $ 33 | $ 29 | $ 45 |  |  |  |  |  |  |  |
Gains on change in fair value of derivatives | $ | 24 | 3 | 28 |  |  |  |  |  |  |  |
Unrealised Loss On Change In Fair Value Of Derivatives | $ | 6 | 4 | (2) |  |  |  |  |  |  |  |
Unrealised Gains On Change In Fair Value Of Derivatives | $ | $ 18 | $ (1) | $ 30 |  |  |  |  |  |  |  |
Electricity | Non-Hedges | Commodity risk management |  |  |  |  |  |  |  |  |  |  |
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |  |  |  |  |  |  |  |  |  |
Notional amount sold | MWh | 16,097,000 | 58,885,000 |  |  |  |  |  |  |  |  |
Notional amount purchased | MWh | 7,204,000 | 37,023,000 |  |  |  |  |  |  |  |  |
Natural gas | Non-Hedges | Commodity risk management |  |  |  |  |  |  |  |  |  |  |
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |  |  |  |  |  |  |  |  |  |
Notional amount sold |  |  |  | 80,413 |  | 38,062,000 |  | 74,194 |  | 80,413,000 |
Notional amount purchased |  |  |  | 110,488 |  | 55,023,000 |  | 103,805 |  | 110,488,000 |
Transmission | Non-Hedges | Commodity risk management |  |  |  |  |  |  |  |  |  |  |
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |  |  |  |  |  |  |  |  |  |
Notional amount sold | MWh | 0 | 29,000 |  |  |  |  |  |  |  |  |
Notional amount purchased | MWh | 1,818,000 | 11,163,000 |  |  |  |  |  |  |  |  |
Emissions | Non-Hedges | Commodity risk management |  |  |  |  |  |  |  |  |  |  |
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |  |  |  |  |  |  |  |  |  |
Notional amount sold | MW |  |  |  |  |  |  | 184,000 |  |  |  | 0
Notional amount purchased | MW |  |  |  |  |  |  | 138,000 |  |  |  | 0
Notional amount sold | t |  |  |  |  | 2,436,000 |  |  |  | 3,134,000 |  |
Notional amount purchased | t |  |  |  |  | 2,446,000 |  |  |  | 2,948,000 |  |

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