v3.19.3.a.u2

Acquisitions, Divestitures and Discontinued Operations (Textuals) (Details) $ in Millions | 3 Months Ended | 9 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | --- | ---
Sep. 30, 2019 USD ($) | Mar. 31, 2017 USD ($) | Sep. 30, 2019 USD ($) | Dec. 31, 2019 USD ($) | Dec. 31, 2018 USD ($) | Dec. 31, 2017 USD ($) | Jul. 10, 2019 MW | Jan. 17, 2017 USD ($)
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Dividends | [1] |  |  |  | $ 1,151 | $ 20 | $ 0 |  |
Impairment losses |  |  |  |  | 84 | 10 | 41 |  |
(Gain) on sale of power plants, net |  |  |  |  | 10 | $ 0 | 27 |  |
North American Power [Member] |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Ownership Percentage of Acquiree |  |  |  |  |  |  |  |  | 100.00%
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net |  |  |  |  |  |  |  |  | $ 105
Garrison Energy Center LLC [Member] |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Power generation capacity | MW |  |  |  |  |  |  |  | 309 |
RockGen Energy LLC [Member] |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Power generation capacity | MW |  |  |  |  |  |  |  | 503 |
Garrison Energy Center and RockGen Energy LLC [Member] |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Ownership Percentage of Divestee |  |  |  |  |  |  |  | 100.00% |
Proceeds from Sale of Productive Assets |  | $ 360 |  |  |  |  |  |  |
Impairment losses |  |  |  |  | $ 55 |  |  |  |
Osprey Energy Center [Member] |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Proceeds from Sale of Productive Assets |  |  | $ 166 |  |  |  |  |  |
(Gain) on sale of power plants, net |  |  |  |  |  |  | $ 27 |  |
Commodity Contract [Member] |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Proceeds from Hedge, Financing Activities |  |  |  | $ 52 |  |  |  |  |
Dividend Paid [Member] |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Dividends |  | $ 400 |  |  |  |  |  |  |
[1] | Dividends paid during the years ended December 31, 2019 and 2018, includes approximately $1 million and $20 million, respectively, in certain Merger-related costs incurred by CPN Management, our parent.

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