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Investments Accounted for by the Equity Method and Variable Interest Entities - Variable Interest Entities (Details) $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2018 USD ($) project MW | Dec. 31, 2017 USD ($)
Schedule of Equity Method Investments [Line Items] |  |
Generation capacity (in MW) | MW | 23,000 |
Equity investments in affiliates | $ 412 | $ 182
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 |
Equity investments in affiliates | $ 37 |
Gladstone |  |
Schedule of Equity Method Investments [Line Items] |  |
Ownership percentage | 37.50% |
Generation capacity (in MW) | MW | 1,613 |
Equity investments in affiliates | $ 140 |

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