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v3.19.3.a.u2

Significant Events - Clean Energy Investment Plan (Details) $ in Millions |  | 12 Months Ended
--- | --- | ---
Oct. 30, 2019 CAD ($) power_purchase_arrangement MW | Dec. 31, 2019 CAD ($) | Dec. 31, 2018 CAD ($) | Dec. 31, 2017 CAD ($)
Investment [Line Items] |  |  |  |
Property, plant and equipment expenditures |  | $ 417 | $ 277 | $ 338
Siemens F Class Gas Turbines And Related Equipment |  |  |  |
Investment [Line Items] |  |  |  |
Number of turbines acquired | power_purchase_arrangement | 2 |  |  |
Capacity of facility (in megawatts) | MW | 230 |  |  |
Property, plant and equipment expenditures | $ 84 |  |  |
Sundance Unit 5 |  |  |  |
Investment [Line Items] |  |  |  |
Capacity of facility (in megawatts) | MW | 730 |  |  |
Sundance Unit 5 | Minimum |  |  |  |
Investment [Line Items] |  |  |  |
Payments for development project expenditure |  | 750 |  |
Sundance Unit 5 | Maximum |  |  |  |
Investment [Line Items] |  |  |  |
Payments for development project expenditure |  | $ 770 |  |

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