v2.4.0.6

Acquisitions and divestments (Details 2) (USD $) | 12 Months Ended |  |  | 0 Months Ended | 1 Months Ended |  |  | 0 Months Ended | 1 Months Ended | 3 Months Ended |  | 1 Months Ended | 3 Months Ended |  | 1 Months Ended |  | 3 Months Ended |  |  | 1 Months Ended |
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Dec. 31, 2012 | Dec. 31, 2011 | Dec. 31, 2010 | Dec. 31, 2012 Minimum | Dec. 31, 2012 Maximum | Nov. 05, 2012 Ridgeline MW | Jul. 31, 2012 Canadian Hills | Dec. 31, 2012 Canadian Hills item | Mar. 31, 2012 Canadian Hills | Mar. 30, 2012 Canadian Hills | Jan. 31, 2012 Canadian Hills MW | Jan. 30, 2013 Auburndale, Lake and Pasco Acquisition | Jan. 31, 2013 Auburndale, Lake and Pasco Acquisition | Jan. 31, 2013 Path 15 Acquisition MMBTU mi | Sep. 30, 2013 Delta-Person Acquisition | Dec. 07, 2012 Delta-Person Acquisition | Sep. 30, 2012 Badger Creek Limited Acquisition | Jun. 30, 2012 Badger Creek Limited Acquisition | Aug. 02, 2012 Badger Creek Limited Acquisition | Feb. 29, 2012 Primary Energy Recycling Corporation | Feb. 16, 2012 Primary Energy Recycling Corporation | Dec. 31, 2011 Onondaga Renewables | Dec. 31, 2012 Onondaga Renewables | Sep. 30, 2011 Onondaga Renewables | May 31, 2011 Topsham | Dec. 31, 2012 Rockland Wind Farm | Dec. 31, 2012 Goshen North MW
Acquisition and divestments |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Percentage acquired in entity |  |  |  |  |  | 100.00% |  |  |  | 48.00% | 51.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Percentage of ownership interest |  |  |  | 5.00% | 50.00% |  |  |  |  | 99.00% |  |  | 100.00% | 100.00% |  | 40.00% |  |  | 50.00% |  | 14.30% |  | 50.00% | 50.00% |  | 50.00% | 12.50%
Wind power project capacity (in MW) |  |  |  |  |  | 40 |  |  |  |  | 300 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 124.5
Percentage of retained interest |  |  |  |  |  |  |  |  |  | 1.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Project-level construction financing facility |  |  |  |  |  |  |  |  |  | $ 310,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Construction loan |  |  |  |  |  |  |  |  |  | 290,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Letter of credit facility |  |  |  |  |  |  |  |  |  | 20,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Letter of credit facility, term |  |  |  |  |  |  |  |  | 5 years |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Investment in equity |  |  |  |  |  |  | 190,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Tax equity investments received |  |  |  |  |  |  |  | 225,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of institutional tax equity investors by whom tax equity investments received |  |  |  |  |  |  |  | 4 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proceeds from sale | 27,925,000 | 8,500,000 | 2,000,000 |  |  |  |  |  |  |  |  |  |  |  | 9,000,000 |  | 3,700,000 |  |  |  |  |  |  |  | 8,500,000 |  |
Own tax equity investment |  |  |  |  |  |  |  | 44,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Short-term debt |  |  |  |  |  |  |  | 265,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Impairment charge on pending sale |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 3,000,000 |  |  |  | 1,500,000 |  |  |  |  |
Entity's common membership interest to be purchased in equity method investee (in shares) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 7,462,830.33 |  |  |  |  |  |  |
Expected proceeds from sale |  |  |  |  |  |  |  |  |  |  |  |  | 111,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Outstanding balance of senior credit facility |  |  |  |  |  |  |  |  |  |  |  |  | 64,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Price of entity's common membership interest in equity method investee |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 24,200,000 |  |  |  |  |  |  |
Management termination fee |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 6,000,000 |  |  |  |  |  |  |
Total price |  |  |  |  |  |  |  |  |  |  |  | 136,000,000 |  |  |  |  |  |  |  | 30,200,000 |  |  |  |  |  |  |
Length of electric transmission line located in California (in miles) |  |  |  |  |  |  |  |  |  |  |  |  |  | 84 |  |  |  |  |  |  |  |  |  |  |  |  |
Capacity of electric transmission line located in California (in kilovolt) |  |  |  |  |  |  |  |  |  |  |  |  |  | 500 |  |  |  |  |  |  |  |  |  |  |  |  |
Gain in equity in earnings of unconsolidated affiliates |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 600,000 |  |  |  |  |  |  |

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- Definition This item represents an other than temporary decline in value that has been recognized against an investment accounted for under the equity method of accounting. The excess of the carrying amount over the fair value of the investment represents the amount of the write down which is or was reflected in earnings. The written down value is a new cost basis with the adjusted value of the investment becoming its new carrying value subject to the equity accounting method. Evidence of a loss in value might include, but would not necessarily be limited to, absence of an ability to recover the carrying amount of the investment or inability of the investee to sustain an earnings capacity which would justify the carrying amount of the investment. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Principles Board Opinion (APB) -Number 18 -Paragraph 19 -Subparagraph h -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 35 -Paragraph 32 -URI http://asc.fasb.org/extlink&oid=7658923&loc=d3e32787-111569 + 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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