v3.3.1.900

Variable Interest Entities and Unconsolidated Investments (Unconsolidated Investements) (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013
Income Loss from Unconsolidated Investments in Power Plants and Distributions [Line Items] |  |  |
(Income) from unconsolidated investments in power plants | $ (24) | $ (25) | $ (30)
Distributions from Equity Method Investments | 25 | 13 | 27
Greenfield [Member] |  |  |
Income Loss from Unconsolidated Investments in Power Plants and Distributions [Line Items] |  |  |
(Income) from unconsolidated investments in power plants | (12) | (10) | (16)
Distributions from Equity Method Investments | 12 | 0 | 18
Whitby [Member] |  |  |
Income Loss from Unconsolidated Investments in Power Plants and Distributions [Line Items] |  |  |
(Income) from unconsolidated investments in power plants | (12) | (15) | (14)
Distributions from Equity Method Investments | $ 13 | $ 13 | $ 9

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