v3.19.2

Divestitures (Details) $ in Millions | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Sep. 30, 2019 USD ($) | Jun. 30, 2019 USD ($) | Jun. 30, 2018 USD ($) | Mar. 31, 2018 USD ($) | Jun. 30, 2019 USD ($) | Jun. 30, 2018 USD ($) | Jul. 10, 2019 MW
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Dividends paid(2) |  |  |  | $ (20) | $ 0 | [1] | $ (18) | [1] |
Impairment losses |  | $ 40 | $ 0 |  | $ 55 |  | $ 0 |  |
Subsequent Event [Member] |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Dividends paid(2) | $ 400 |  |  |  |  |  |  |  |
Subsequent Event [Member] | Garrison Energy Center and RockGen Energy LLC [Member] |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Ownership percentage of acquiree |  |  |  |  |  |  |  |  | 100.00%
Proceeds from Sale of Productive Assets | $ 360 |  |  |  |  |  |  |  |
Subsequent Event [Member] | Garrison Energy Center LLC [Member] |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Power generation capacity | MW |  |  |  |  |  |  |  |  | 309
Subsequent Event [Member] | RockGen Energy LLC [Member] |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Power generation capacity | MW |  |  |  |  |  |  |  |  | 503
[1] | Subsequent to the consummation of the Merger on March 8, 2018, we paid certain Merger-related costs incurred by CPN Management, our direct parent.

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