v2.4.0.6

Goodwill, transmission system rights, power purchase agreements and development intangible assets and liabilities (Details 3) (USD $) In Thousands, unless otherwise specified | 12 Months Ended
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Dec. 31, 2012
Weighted average remaining amortization period related to our intangible assets |
Weighted average remaining amortization period | 9 years
Power Purchase Agreements |
Estimated future amortization |
2013 | 60,199
2014 | 60,527
2015 | 56,802
2016 | 56,802
2017 | 56,802
Weighted average remaining amortization period related to our intangible assets |
Weighted average remaining amortization period | 9 years
Fuel Supply Agreements |
Estimated future amortization |
2013 | (1,173)
2014 | (1,173)
2015 | (1,173)
2016 | (1,173)
2017 | (1,173)
Weighted average remaining amortization period related to our intangible assets |
Weighted average remaining amortization period | 10 years

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- Definition Amount of amortization expense expected to be recognized during the next fiscal year following the latest fiscal year for assets, excluding financial assets and goodwill, lacking physical substance with a finite life. + 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)(3) -URI http://asc.fasb.org/extlink&oid=7658586&loc=d3e16323-109275 + Details
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- Definition Amount of amortization expense expected to be recognized during the fifth fiscal year following the latest fiscal year for assets, excluding financial assets and goodwill, lacking physical substance with a finite life. + 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)(3) -URI http://asc.fasb.org/extlink&oid=7658586&loc=d3e16323-109275 + Details
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- Definition Amount of amortization expense expected to be recognized during the fourth fiscal year following the latest fiscal year for assets, excluding financial assets and goodwill, lacking physical substance with a finite life. + 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)(3) -URI http://asc.fasb.org/extlink&oid=7658586&loc=d3e16323-109275 + Details
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- Definition Amount of amortization expense expected to be recognized during the third fiscal year following the latest fiscal year for assets, excluding financial assets and goodwill, lacking physical substance with a finite life. + 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)(3) -URI http://asc.fasb.org/extlink&oid=7658586&loc=d3e16323-109275 + Details
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- Definition Amount of amortization expense expected to be recognized during the second fiscal year following the latest fiscal year for assets, excluding financial assets and goodwill, lacking physical substance with a finite life. + 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)(3) -URI http://asc.fasb.org/extlink&oid=7658586&loc=d3e16323-109275 + Details
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