v3.3.1.900

Variable Interest Entities and Unconsolidated Investments (VIE Textuals) (Details) | 12 Months Ended
--- | ---
Dec. 31, 2015 USD ($) yr MW | Dec. 31, 2014 USD ($) MW | Dec. 31, 2013 USD ($)
Schedule of Equity Method Investments [Line Items] |  |  |
Variable Interest Entity, Financial or Other Support, Amount | $ | $ 4,000,000 | $ 47,000,000 | $ 0
Equity Method Investment, Summarized Financial Information, Debt | $ | 269,000,000 | 342,000,000 |
Prorata Share of Equity Method Investment, Summarized Financial Information, Debt | $ | $ 135,000,000 | $ 171,000,000 |
Greenfield [Member] |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Minority Interest Ownership Percentage By Noncontrolling Third Party Owners | 50.00% |  |
Whitby [Member] |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Minority Interest Ownership Percentage By Noncontrolling Third Party Owners | 50.00% |  |
Russell City Energy [Member] |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Minority Interest Ownership Percentage By Noncontrolling Third Party Owners | 25.00% |  |
Equity Method Investment, Ownership Percentage | 75.00% |  |
Variable Interest Entity, Primary Beneficiary [Member] |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Power generation capacity | 10,266 | 10,365 |
Inland Empire Energy Center [Member] |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Power generation capacity | 775 |  |
Put Option Exercise Period | yr | 2,025 |  |
Minimum [Member] | Inland Empire Energy Center [Member] |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Call Option Exercise Period | yr | 2,017 |  |
Maximum [Member] | Inland Empire Energy Center [Member] |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Call Option Exercise Period | yr | 2,024 |  |
Greenfield [Member] |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Power generation capacity | 1,038 |  |
Equity Method Investment, Ownership Percentage | 50.00% |  |
Whitby [Member] |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Power generation capacity | 50 |  |
Equity Method Investment, Ownership Percentage | 50.00% |  |

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- Definition The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=6382943&loc=d3e33918-111571 + Details
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