v2.4.0.6

Variable Interest Entities and Unconsolidated Investments (VIE Textuals) (Details) (USD $) In Millions, unless otherwise specified | 12 Months Ended
--- | ---
Dec. 31, 2012 MW | Dec. 31, 2011 MW | Dec. 31, 2010
Schedule of Equity Method Investments [Line Items] |  |  |
Power generation capacity | 8,255 | 11,391 |
Variable Interest Entity, Financial or Other Support, Amount | $ 20 | $ 87 | $ 46
Equity Method Investment, Summarized Financial Information, Debt | 448 | 462 |
Prorata Share of Equity Method Investment, Summarized Financial Information, Debt | 224 | 231 |
OMEC [Member] |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Power generation capacity | 608 |  |
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% |  |
Inland Empire Energy Center [Member] |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Power generation capacity | 775 |  |
Put Option Exercise Period | 2,025 |  |
Minimum [Member] | Inland Empire Energy Center [Member] |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Call Option Exercise Period | 2,017 |  |
Maximum [Member] | Inland Empire Energy Center [Member] |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Call Option Exercise Period | 2,024 |  |
Greenfield [Member] |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Power generation capacity | 1,038 |  |
Equity Method Investment, Ownership Percentage | 50.00% |  |
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% |  |
Whitby [Member] |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Power generation capacity | 50 |  |
Equity Method Investment, Ownership Percentage | 50.00% |  |
NDH [Member] |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Variable Interest Entity, Financial or Other Support, Amount |  |  | 540
York Energy Center [Member] |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Variable Interest Entity, Financial or Other Support, Amount |  |  | $ 110

X
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- Definition Equity Method Investment, Summarized Financial Information, Term Loan + References No definition available. + Details
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- Definition Minority Interest Ownership Percentage By Noncontrolling Third Party Owners + References No definition available. + Details
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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 Project financing interest rate spread - Canadian Prime Rate + 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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