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Significant Events - Skookumchuck Wind Energy Facility (Details) $ in Millions | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2019 CAD ($) MW | Dec. 31, 2019 CAD ($) MW | Nov. 01, 2019 MMcf | Dec. 17, 2018 MMcf
Skookumchuck Wind Energy Facility |  |  |  |
Investment [Line Items] |  |  |  |
Proportion of ownership interest in joint operation | 49.00% |  |  |
Capacity of facility (in megawatts) | MW | 136.8 | 136.8 |  |
Skookumchuck Wind Energy Facility | Minimum |  |  |  |
Investment [Line Items] |  |  |  |
Payments for development project expenditure | $ 150 |  |  |
Skookumchuck Wind Energy Facility | Maximum |  |  |  |
Investment [Line Items] |  |  |  |
Payments for development project expenditure | 160 |  |  |
Tidewater Brazeau River Pipeline | Tidewater |  |  |  |
Investment [Line Items] |  |  |  |
Payments for development project expenditure | $ 83 | $ 100 |  |
Future option to acquire pipeline, ownership percentage |  |  |  | 50.00%
Natural gas pipeline capacity (mmcf) | MMcf |  |  | 130 | 50

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