v3.20.2

Variable Interest Entities and Unconsolidated Investments (VIE Texuals) (Details) $ in Millions | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2020 USD ($) MW | Mar. 31, 2020 USD ($) | Jun. 30, 2019 USD ($) | Jun. 30, 2020 USD ($) MW | Jun. 30, 2019 USD ($) | Dec. 31, 2019 USD ($) MW
Variable Interest Entity [Line Items] |  |  |  |  |  |
Equity method investment, ownership percentage | 50.00% |  |  | 50.00% |  |
Adjustments to additional paid in capital, other |  | $ 67 |  |  |  |
Equity method investment, summarized financial information, debt | $ 276 |  |  | $ 276 |  | $ 299
Prorata share of equity method investment, summarized financial information, debt | 138 |  |  | 138 |  | $ 150
Return on investments from unconsolidated subsidiaries |  |  |  | 0 | $ 11 |
Variable interest entity, financial or other support, amount | $ 0 |  | $ 0 | $ 0 |  |
Greenfield |  |  |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |  |  |
Power generation capacity | MW | 1,038 |  |  | 1,038 |  |
Equity method investment, ownership percentage | 50.00% |  |  | 50.00% |  |
Return on investments from unconsolidated subsidiaries |  |  |  | $ 0 |  |
Calpine Receivables |  |  |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |  |  |
Equity method investment, ownership percentage | 100.00% |  |  | 100.00% |  |
Variable interest entity, reporting entity involvement, maximum loss exposure, amount | $ 51 |  |  | $ 51 |  |
Whitby |  |  |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |  |  |
Return on investments from unconsolidated subsidiaries |  |  | $ 0 |  | $ 11 |
Variable Interest Entity, Primary Beneficiary |  |  |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |  |  |
Power generation capacity | MW | 7,354 |  |  | 7,354 |  | 6,669
Russell City Energy |  |  |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |  |  |
Minority interest ownership percentage by noncontrolling third party owners |  |  |  |  |  | 25.00%
Payments to Acquire Business |  | 35 |  |  |  |
Acquisition of noncontrolling interest |  | 49 |  |  |  |
Working Capital Adjustment to Sale Price |  | $ 14 |  |  |  |

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