v2.4.0.6

Variable Interest Entities and Unconsolidated Investments (VIE Textuals) (Details) In Millions, unless otherwise specified | 3 Months Ended | 9 Months Ended |  | 3 Months Ended | 9 Months Ended |  | 3 Months Ended | 9 Months Ended |
--- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Sep. 30, 2012 USD ($) MW | Sep. 30, 2011 USD ($) | Sep. 30, 2012 USD ($) MW | Sep. 30, 2011 USD ($) | Dec. 31, 2011 USD ($) MW | Sep. 30, 2012 Greenfield [Member] USD ($) | Sep. 30, 2011 Greenfield [Member] USD ($) | Sep. 30, 2012 Greenfield [Member] USD ($) | Sep. 30, 2011 Greenfield [Member] USD ($) | Sep. 30, 2012 Greenfield [Member] CAD MW | Sep. 30, 2012 Whitby [Member] USD ($) MW | Sep. 30, 2011 Whitby [Member] USD ($) | Sep. 30, 2012 Whitby [Member] USD ($) MW | Sep. 30, 2011 Whitby [Member] USD ($) | Sep. 30, 2012 Inland Empire Energy Center [Member] Y MW | Sep. 30, 2012 Inland Empire Energy Center [Member] Maximum [Member] Y | Sep. 30, 2012 Inland Empire Energy Center [Member] Minimum [Member] Y
Variable Interest Entity [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Power generation capacity | 10,500 |  | 10,500 |  | 11,391 |  |  |  |  | 1,038 | 50 |  | 50 |  | 775 |  |
Variable Interest Entity, Financial or Other Support, Amount | $ 0 | $ 15 | $ 0 | $ 87 |  |  |  |  |  |  |  |  |  |  |  |  |
Equity Method Investment, Ownership Percentage |  |  |  |  |  |  |  |  |  | 50.00% | 50.00% |  | 50.00% |  |  |  |
Equity Method Investment, Summarized Financial Information, Debt | 460 |  | 460 |  | 462 |  |  |  |  |  |  |  |  |  |  |  |
Prorata Share of Equity Method Investment, Summarized Financial Information, Debt | 230 |  | 230 |  | 231 |  |  |  |  |  |  |  |  |  |  |  |
Equity Method Investment, Summarized Financial Information, Term Loan Period |  |  |  |  |  |  |  |  |  | 18 years |  |  |  |  |  |  |
Equity Method Investment, Summarized Financial Information, Term Loan |  |  |  |  |  |  |  |  |  | 648 |  |  |  |  |  |  |
Project financing interest rate spread - Canadian LIBOR |  |  |  |  |  |  |  |  |  | 1.125% |  |  |  |  |  |  |
Project financing interest rate spread - Canadian Prime Rate |  |  |  |  |  |  |  |  |  | 0.125% |  |  |  |  |  |  |
Distribution from equity method investee |  |  |  |  |  | $ 9 | $ 0 | $ 18 | $ 2 |  | $ 0 | $ 0 | $ 7 | $ 4 |  |  |
Call Option Exercise Period |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 2,024 | 2,017
Put Option Exercise Period |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 2,025 |  |

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- Definition Power generation capacity + References No definition available. + Details
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- Definition Project financing interest rate spread - Canadian LIBOR + References No definition available. + Details
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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 Statement of Financial Accounting Standard (FAS) -Number 159 -Paragraph 18 -Subparagraph f -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 2: 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 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Principles Board Opinion (APB) -Number 18 -Paragraph 20 -Subparagraph a (1) -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. + Details
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- Definition The amount of financial or other support the reporting entity has provided (explicitly or implicitly) to the Variable Interest Entity (VIE) that it was not previously contractually required to provide or that the reporting entity intends to provide, including, for example, situations in which the reporting entity assisted the VIE in obtaining another type of support. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 50 -Paragraph 5A -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=7880789&loc=SL6759159-111685 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name FASB Staff Position (FSP) -Number FAS140-4/FIN46(R)-8 -Paragraph C4 -Subparagraph c -Clause 1 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. + Details
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