v2.4.0.6

Equity method investments (Details) (USD $) In Thousands, unless otherwise specified | 12 Months Ended |  |  | 12 Months Ended |  | 12 Months Ended |  | 12 Months Ended |  | 12 Months Ended |  | 12 Months Ended |  | 12 Months Ended
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Dec. 31, 2012 | Dec. 31, 2011 | Dec. 31, 2010 | Dec. 31, 2012 Frederickson | Dec. 31, 2011 Frederickson | Dec. 31, 2012 Badger Creek Limited | Dec. 31, 2011 Badger Creek Limited | Dec. 31, 2010 Badger Creek Limited | Dec. 31, 2012 Orlando Cogen, LP | Dec. 31, 2011 Orlando Cogen, LP | Dec. 31, 2010 Orlando Cogen, LP | Dec. 31, 2012 Onondaga Renewables, LLC | Dec. 31, 2011 Onondaga Renewables, LLC | Dec. 31, 2010 Onondaga Renewables, LLC | Sep. 30, 2011 Onondaga Renewables, LLC | Dec. 31, 2012 Koma Kulshan Associates | Dec. 31, 2011 Koma Kulshan Associates | Dec. 31, 2010 Koma Kulshan Associates | Dec. 31, 2012 Chambers Cogen, LP | Dec. 31, 2011 Chambers Cogen, LP | Dec. 31, 2010 Chambers Cogen, LP | Dec. 31, 2012 Delta-Person, LP | Dec. 31, 2012 Rockland Wind Farm | Dec. 31, 2011 Rockland Wind Farm | Dec. 31, 2012 Idaho Wind Partners 1, LLC | Dec. 31, 2011 Idaho Wind Partners 1, LLC | Dec. 31, 2010 Idaho Wind Partners 1, LLC | Dec. 31, 2012 Selkirk Cogen Partners, LP | Dec. 31, 2011 Selkirk Cogen Partners, LP | Dec. 31, 2010 Selkirk Cogen Partners, LP | Dec. 31, 2012 Gregory Power Partners, LP | Dec. 31, 2011 Gregory Power Partners, LP | Dec. 31, 2010 Gregory Power Partners, LP | Dec. 31, 2012 Goshen North | Dec. 31, 2012 PERH | Dec. 31, 2011 PERH | Feb. 16, 2012 PERH | Dec. 31, 2012 Other | Dec. 31, 2011 Other | Dec. 31, 2010 Other | Dec. 31, 2012 Power L.P. | Dec. 31, 2011 Power L.P.
Equity method investments |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Percentage of ownership interest |  |  |  | 50.00% |  |  |  |  | 50.00% |  |  | 50.00% |  |  | 50.00% | 49.80% |  |  | 40.00% |  |  | 40.00% | 50.00% |  | 27.60% |  |  | 18.50% |  |  | 17.10% |  |  | 12.50% |  |  | 14.30% |  |  |  |  |
Carrying value | $ 428,690 | $ 474,351 |  | $ 167,723 | $ 166,837 |  | $ 6,477 |  | $ 19,930 | $ 25,955 |  | $ 167 | $ 291 |  |  | $ 6,393 | $ 5,856 |  | $ 154,300 | $ 143,797 |  |  |  | $ 12,500 | $ 34,703 | $ 36,143 |  | $ 33,700 | $ 47,357 |  | $ 2,796 | $ 3,520 |  | $ 8,978 |  | $ 25,609 |  |  | $ 9 |  |  |
Percentage of ownership, before increase |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 30.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Equity in earnings of unconsolidated affiliates | 15,246 | 6,356 | 13,777 |  |  | (2,778) | (4) | 749 | 3,200 | 863 | 2,031 | (433) | (1,761) | (320) |  | 537 | 483 | 452 | 17,082 | 7,739 | 13,144 |  | (7,997) |  | (193) | (1,563) | (126) | 7,640 | (406) | (3,454) | (725) | 524 | 2,162 |  | (1,963) | 38 |  | (10) | (1) | (861) | 886 | 444
Distributions from equity method investments | (38,347) | (21,889) | (16,843) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Equity in earnings (loss) of unconsolidated affiliates, net of distributions | $ (23,101) | $ (15,533) | $ (3,066) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |

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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 before stock transaction. + References No definition available. + Details
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- Definition This item represents disclosure of the amount of dividends or other distributions received from unconsolidated subsidiaries, certain corporate joint ventures, and certain noncontrolled corporation; these investments are accounted for under the equity method of accounting. This element excludes distributions that constitute a return of investment, which are classified as investing activities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 13 -Article 5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 28 -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 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3602-108585 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Principles Board Opinion (APB) -Number 18 -Paragraph 19 -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 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 This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.12) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=16385135&loc=d3e33749-111570 + Details
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- Definition This item represents the entity's proportionate share for the period of the net income (loss) of its investee (such as unconsolidated subsidiaries and joint ventures) to which the equity method of accounting is applied. This item includes income or expense related to stock-based compensation based on the investor's grant of stock to employees of an equity method investee. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.12) -URI http://asc.fasb.org/extlink&oid=6880815&loc=d3e20235-122688 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3602-108585 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 9 -Article 5 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 28 -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 5: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 11 -Article 7 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=16385135&loc=d3e33749-111570 Reference 7: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Principles Board Opinion (APB) -Number 18 -Paragraph 6 -Subparagraph b -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 8: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Principles Board Opinion (APB) -Number 18 -Paragraph 19 -Subparagraph c -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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