v3.19.1

Variable Interest Entities and Unconsolidated Investments in Power Plants (VIE Texuals) (Details) $ in Millions | 3 Months Ended |
--- | --- | ---
Mar. 31, 2019 USD ($) yr MW | Mar. 31, 2018 USD ($) | Dec. 31, 2018 USD ($) MW
Variable Interest Entity [Line Items] |  |  |
Variable interest entity, financial or other support, amount | $ 0 | $ 0 |
Equity method investment, ownership percentage | 50.00% |  |
Equity method investment, summarized financial information, debt | $ 302 |  | $ 301
Prorata share of equity method investment, summarized financial information, debt | 151 |  | $ 151
Return on investments from unconsolidated subsidiaries | $ 11 | 3 |
Greenfield [Member] |  |  |
Variable Interest Entity [Line Items] |  |  |
Power generation capacity | MW | 1,038 |  |
Equity method investment, ownership percentage | 50.00% |  |
Return on investments from unconsolidated subsidiaries | $ 0 | 0 |
Whitby [Member] |  |  |
Variable Interest Entity [Line Items] |  |  |
Power generation capacity | MW | 50 |  |
Equity method investment, ownership percentage | 50.00% |  |
Return on investments from unconsolidated subsidiaries | $ 11 | $ 3 |
Calpine Receivables [Member] |  |  |
Variable Interest Entity [Line Items] |  |  |
Variable Interest Entity, Reporting Entity Involvement, Maximum Loss Exposure, Amount | $ 60 |  |
Equity method investment, ownership percentage | 100.00% |  |
Variable Interest Entity, Primary Beneficiary [Member] |  |  |
Variable Interest Entity [Line Items] |  |  |
Power generation capacity | MW | 7,880 |  | 7,880
Put Option [Member] |  |  |
Variable Interest Entity [Line Items] |  |  |
Proceeds from sale of property, plant and equipment | $ 280 |  |
Call Option [Member] |  |  |
Variable Interest Entity [Line Items] |  |  |
Proceeds from sale of property, plant and equipment | $ 377 |  |
Inland Empire Energy Center [Member] |  |  |
Variable Interest Entity [Line Items] |  |  |
Power generation capacity | MW | 775 |  |
Put Option Exercise Period | yr | 2,025 |  |
Inland Empire Energy Center [Member] | Minimum [Member] |  |  |
Variable Interest Entity [Line Items] |  |  |
Call Option Exercise Period | yr | 2,017 |  |
Inland Empire Energy Center [Member] | Maximum [Member] |  |  |
Variable Interest Entity [Line Items] |  |  |
Call Option Exercise Period | yr | 2,024 |  |
OMEC [Member] |  |  |
Variable Interest Entity [Line Items] |  |  |
Debt Instrument, Face Amount | $ 220 |  |

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