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Investments Accounted for by the Equity Method and Variable Interest Entities - Variable Interest Entities (Details) $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Jun. 30, 2018 USD ($) | Dec. 31, 2020 project MW | Dec. 31, 2019 USD ($)
Schedule of Equity Method Investments [Line Items] |  |  |
Generation capacity (in MW) | MW |  | 23,000 |
Ivanpah Master Holdings LLC |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Ownership percentage |  | 54.50% |
Number of solar electric generating projects | project |  | 3 |
Generation capacity (in MW) | MW |  | 393 |
Release of reserves to fund equity distributions | $ 95 |  |
Loss on deconsolidation |  |  | $ 22
Reduction of assets due to deconsolidation |  |  | 1,300
Reduction of liabilities due to deconsolidation |  |  | $ 1,200
Gladstone |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Ownership percentage |  | 37.50% |
Generation capacity (in MW) | MW |  | 1,613 |

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