v2.4.0.6

Goodwill, transmission system rights, power purchase agreements and development intangible assets and liabilities (Tables) | 12 Months Ended
--- | ---
Dec. 31, 2012
Goodwill, transmission system rights, power purchase agreements and development intangible assets and liabilities |
Schedule of changes in the carrying amount of goodwill |
|  | Northeast |  | Northwest |  | Southwest |  | Un-allocated corporate |  | Total |
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Balance at December 31, 2010 |  | $ | — |  | $ | — |  | $ | 8,918 |  | $ | 3,535 |  | $ | 12,453 |
Acquisition of businesses |  |  | 135,268 |  |  | 138,263 |  |  | 57,602 |  |  | — |  |  | 331,133 |
Balance at December 31, 2011 |  |  | 135,268 |  |  | 138,263 |  |  | 66,520 |  |  | 3,535 |  |  | 343,586 |
Reclass to assets held for sale |  |  | — |  |  | — |  |  | (8,918 | ) |  | — |  |  | (8,918 | )
Balance at December 31, 2012 |  | $ | 135,268 |  | $ | 138,263 |  | $ | 57,602 |  | $ | 3,535 |  | $ | 334,668 |
Schedule of components of intangible assets subject to amortization |
|  | Other Intangible Assets, Net |
--- | --- | --- | ---
|  | Power Purchase Agreements |  | Development Costs |  | Total |
Gross balances, December 31, 2012 |  | $ | 590,923 |  | $ | 6,164 |  | $ | 597,087 |
Less: accumulated amortization |  |  | (76,897 | ) |  | — |  |  | (76,897 | )
Foreign currency translation adjustment |  |  | 4,693 |  |  | — |  |  | 4,693 |
Net carrying amount, December 31, 2012 |  | $ | 518,719 |  | $ | 6,164 |  | $ | 524,883 |
|  | Other Intangible Assets, Net |  |  |
--- | --- | --- | --- | --- | ---
|  | Power Purchase Agreements |  | Fuel Supply Agreements |  | Development Costs |  | Total |  | Transmission System Rights |
Gross balances, December 31, 2011 |  | $ | 639,699 |  | $ | 33,845 |  | $ | 1,786 |  | $ | 675,330 |  | $ | 231,669 |
Less: accumulated amortization |  |  | (63,908 | ) |  | (26,271 | ) |  | — |  |  | (90,179 | ) |  | — |
Foreign currency translation adjustment |  |  | (877 | ) |  | — |  |  | — |  |  | (877 | ) |  | (51,387 | )
Net carrying amount, December 31, 2011 |  | $ | 574,914 |  | $ | 7,574 |  | $ | 1,786 |  | $ | 584,274 |  | $ | 180,282 |
|  | Power Purchase and Fuel supply Agreement Liabilities, Net |
--- | --- | --- | ---
|  | Power Purchase Agreements |  | Fuel Supply Agreements |  | Total |
Gross balances, December 31, 2012 |  | $ | (35,287 | ) | $ | (12,613 | ) | $ | (47,900 | )
Less: accumulated amortization |  |  | 2,884 |  |  | 1,564 |  |  | 4,448 |
Foreign currency translation adjustment |  |  | (557 | ) |  | — |  |  | (557 | )
Net carrying amount, December 31, 2012 |  | $ | (32,960 | ) | $ | (11,049 | ) | $ | (44,009 | )
|  | Power Purchase and Fuel supply Agreement Liabilities, Net |
--- | --- | --- | ---
|  | Power Purchase Agreements |  | Fuel Supply Agreements |  | Total |
Gross balances, December 31, 2011 |  | $ | (35,288 | ) | $ | (38,106 | ) | $ | (73,394 | )
Less: accumulated amortization |  |  | 398 |  |  | 973 |  |  | 1,371 |
Foreign currency translation adjustment |  |  | 127 |  |  | 121 |  |  | 248 |
Net carrying amount, December 31, 2011 |  | $ | (34,763 | ) | $ | (37,012 | ) | $ | (71,775 | )
Schedule of amortization of intangible assets |
|  | 2012 |  | 2011 |  | 2010 |
--- | --- | --- | --- | --- | --- | --- | ---
Power purchase agreements |  | $ | 66,168 |  | $ | 11,586 |  | $ | — |
Fuel supply agreements |  |  | (1,096 | ) |  | (1,370 | ) |  | — |
Total amortization |  | $ | 65,072 |  | $ | 10,216 |  | $ | — |
Schedule of estimated future amortization for the next five years |
Year Ended December 31, |  | Power Purchase Agreements |  | Fuel Supply Agreements |
--- | --- | --- | --- | --- | ---
2013 |  | $ | 60,199 |  | $ | (1,173 | )
2014 |  |  | 60,527 |  |  | (1,173 | )
2015 |  |  | 56,802 |  |  | (1,173 | )
2016 |  |  | 56,802 |  |  | (1,173 | )
2017 |  |  | 56,802 |  |  | (1,173 | )
Schedule of weighted average remaining amortization period related to the entity's intangible assets |
As of December 31, 2012 |  | Power Purchase Agreements |  | Fuel Supply Agreements |  | Total |
--- | --- | --- | --- | --- | --- | --- | ---
(in years) |  |  |  |  |  |  |
Weighted average remaining amortization period |  |  | 9.0 |  |  | 10.0 |  |  | 9.0 |

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- Definition Tabular disclosure of assets, excluding financial assets and goodwill, lacking physical substance with a finite life, by either major class or business segment. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=7658586&loc=d3e16323-109275 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=7658586&loc=d3e16265-109275 + Details
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- Definition Tabular disclosure of goodwill by reportable segment and in total which includes a rollforward schedule. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 142 -Paragraph 45 -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. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 142 -Paragraph 47 -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 350 -SubTopic 20 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=14024403&loc=d3e13854-109267 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=14024403&loc=d3e13816-109267 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 142 -Paragraph 45 -Subparagraph e -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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