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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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 30

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 142

-Paragraph 45

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-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.



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-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.



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