Discontinued Operations And Held For Sale Businesses (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Gain (loss) on disposal and impairment, after taxes	$ 16	$ 86	$ 64
(Gain) loss on disposal and impairment write-down before tax and NCI	84	388	209
Tax effect of gain on disposal of discontinued operations	68	300	132
Asset impairment expense	73	173	304
Fair Value of nonrecurring measurement	35
Discontinued Operations Income Loss
Revenue	66	836	1,695
Income (loss) from operations of discontinued businesses	(10)	(157)	(770)
Income tax (expense) benefit	(3)	26	284
Income (loss) from operations of discontinued businesses	(13)	(131)	(486)
Net gain/(loss) on sale and impairments of discontinued operations, net of tax	16	86	64
Red Oak [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Generation Capacity (MW)	832
Ironwood [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Generation Capacity (MW)	710
Red Oak and Ironwood [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Divestiture Of Ownership In Subsidiary Percent		100.00%
Sale Proceeds	228
Gain (loss) on disposal and impairment, after taxes	73	0	0
(Gain) loss on disposal and impairment write-down before tax and NCI	73
Discontinued Operations Income Loss
Net gain/(loss) on sale and impairments of discontinued operations, net of tax	73	0	0
Eastern Energy Subsidiary [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Generation Capacity (MW)		1,169
Gain (loss) on disposal and impairment, after taxes	30	0	0
Asset impairment expense		827
Discontinued Operations Income Loss
Net gain/(loss) on sale and impairments of discontinued operations, net of tax	30	0	0
Tisza I I Subsidiary [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Generation Capacity (MW)	900
Divestiture Of Ownership In Subsidiary Percent	100.00%
Sale Proceeds	14
Gain (loss) on disposal and impairment, after taxes	(87)	0	0
Asset impairment expense		52	85
Loss recognized due to CTA	73
Discontinued Operations Income Loss
Net gain/(loss) on sale and impairments of discontinued operations, net of tax	(87)	0	0
Carbon Reduction Projects [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Divestiture Of Ownership In Subsidiary Percent		100.00%
Gain (loss) on disposal and impairment, after taxes	(6)	0	0
Asset impairment expense		40
Fair Value of nonrecurring measurement		0
Carrying Amount		49
Discontinued Operations Income Loss
Net gain/(loss) on sale and impairments of discontinued operations, net of tax	(6)	0	0
Edes [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Divestiture Of Ownership In Subsidiary Percent		90.00%
Customers Served		172,000
Edelap [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Divestiture Of Ownership In Subsidiary Percent		90.00%
Customers Served		329,000
Brazil Telecom [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Divestiture Of Ownership In Subsidiary Percent		46.00%
Sale Proceeds		893
Gain (loss) on disposal and impairment, after taxes	6	446	0
Discontinued Operations Income Loss
Net gain/(loss) on sale and impairments of discontinued operations, net of tax	6	446	0
Argentina Distribution [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Gain (loss) on disposal and impairment, after taxes	0	(338)	0
Discontinued Operations Income Loss
Net gain/(loss) on sale and impairments of discontinued operations, net of tax	0	(338)	0
Wind projects [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Gain (loss) on disposal and impairment, after taxes	0	(22)	0
Discontinued Operations Income Loss
Net gain/(loss) on sale and impairments of discontinued operations, net of tax	0	(22)	0
Subsidiary Barka [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Generation Capacity (MW)			456
Divestiture Of Ownership In Subsidiary Percent			35.00%
Sale Proceeds			170
Sale Proceeds AES Portion			124
Gain (loss) on disposal and impairment, after taxes	0	0	80
Discontinued Operations Income Loss
Net gain/(loss) on sale and impairments of discontinued operations, net of tax	0	0	80
Barka Related Service Companies [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Divestiture Of Ownership In Subsidiary Percent			100.00%
Lal Pir and Pak Gen [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Divestiture Of Ownership In Subsidiary Percent			55.00%
Sale Proceeds			117
Sale Proceeds AES Portion			65
Gain (loss) on disposal and impairment, after taxes	0	0	(22)
Discontinued Operations Income Loss
Net gain/(loss) on sale and impairments of discontinued operations, net of tax	0	0	(22)
Ras Laffan [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Generation Capacity (MW)			756
Divestiture Of Ownership In Subsidiary Percent			55.00%
Sale Proceeds			234
Gain (loss) on disposal and impairment, after taxes	0	0	6
Discontinued Operations Income Loss
Net gain/(loss) on sale and impairments of discontinued operations, net of tax	$ 0	$ 0	$ 6
Borsod [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Generation Capacity (MW)		161
Thames [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Generation Capacity (MW)		208
Lal Pir [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Generation Capacity (MW)			362
Pak Gen [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Generation Capacity (MW)			365