Goodwill and Other Intangible Assets (Tables)

12 Months Ended

Dec. 31, 2011

Goodwill And Other Intangible Assets Tables [Abstract]

Goodwill By Segments

			Latin		Latin		North		North
			America -		America -		America -		America -		Europe -		Asia -		Corporate
			Generation		Utilities		Generation		Utilities		Generation		Generation		and Other		Total
Balance as of December 31, 2009
	Goodwill		$	926	$	140	$	111	$	-	$	137	$	78	$	101	$	1,493
	Accumulated impairment losses			(24)		(7)		(20)		-		(137)		-		(6)		(194)
		Net balance		902		133		91		-		-		78		95		1,299
	Impairment losses			-		-		(18)		-		-		-		(3)		(21)
	Foreign currency translation
		and other		-		-		(10)		-		-		3		-		(7)
Balance as of December 31, 2010
	Goodwill			926		140		101		-		137		81		101		1,486
	Accumulated impairment losses			(24)		(7)		(38)		-		(137)		-		(9)		(215)
		Net balance		902		133		63		-		-		81		92		1,271
	Impairment losses			-		-		-		-		-		(17)		-		(17)
	Goodwill acquired during the year(1)			-		-		-		2,489		-		-		-		2,489
	Foreign currency translation
		and other		-		-		(10)		-		-		-		-		(10)
Balance as of December 31, 2011
	Goodwill			926		140		91		2,489		137		81		101		3,965
	Accumulated impairment losses			(24)		(7)		(38)		-		(137)		(17)		(9)		(232)
		Net balance	$	902	$	133	$	53	$	2,489	$	-	$	64	$	92	$	3,733

Other Intangible Assets

		December 31, 2011						December 31, 2010
		Gross		Accumulated		Net		Gross		Accumulated		Net
		Balance		Amortization		Balance		Balance		Amortization		Balance
			(in millions)					(in millions)
Subject to Amortization
Project development rights(1)		$	102	$	-	$	102	$	117	$	-	$	117
Sales concessions			156		(92)		64		162		(89)		73
Contractual payment rights(2)			69		(13)		56		65		(4)		61
Land use rights			49		(4)		45		50		(2)		48
Management rights			39		(13)		26		66		(30)		36
Emission allowances(3)			18		-		18		8		-		8
Electric security plan			88		(9)		79		-		-		-
Customer contracts			45		(3)		42		-		-		-
Customer relationships			30		-		30		-		-		-
Other(4)			71		(30)		41		70		(26)		44
	Subtotal		667		(164)		503		538		(151)		387
Indefinite-Lived Intangible Assets
Land use rights			52		-		52		51		-		51
Emission allowances(5)			4		-		4		8		-		8
Trademark/Trade name			5		-		5		-		-		-
Other			2		-		2		2		-		2
	Subtotal		63		-		63		61		-		61
Total		$	730	$	(164)	$	566	$	599	$	(151)	$	448

Schedule Of Acquired Intangible Assets By Major Class [Text Block]

	December 31, 2011
			Subject to
			Amortization/	Weighted Average		Amortization
	Amount		Indefinite-Lived	Amortization Period		Method
	(in millions)			(in years)
Electric security plan(2)	$	88	Subject to amortization		1		Straight line
Customer relationship(1) (3)		30	Subject to amortization		12		Straight line
Customer contracts(1) (4)		45	Subject to amortization		3		Other
Trademark/Trade name(1) (5)		5	Indefinite-lived		N/A		N/A
Other		4	Subject to amortization		Various		As utilized
Total	$	172
	December 31, 2010
			Subject to
			Amortization/	Weighted Average		Amortization
	Amount		Indefinite-Lived	Amortization Period		Method
	(in millions)			(in years)
Project development rights	$	141	Subject to amortization		Various		Straight line
Contractual payment rights		65	Subject to amortization		10		Straight line
Emission allowances		14	Subject to amortization		Various		As utilized
Land use rights		7	Indefinite-lived		N/A		N/A
Total	$	227

Schedule of Expected Amortization Expense [Table Text Block]

	Estimated amortization expense
	2012		2013		2014		2015		2016
		(in millions)
Contractual payment rights	$	9	$	9	$	9	$	9	$	3
Sales concessions		6		6		6		6		5
Customer relationships & contracts		35		11		4		3		3
Electric security plan		79		-		-		-		-
All other		9		6		4		4		4
Total	$	138	$	32	$	23	$	22	$	15