Subsequent Events (Details) (subsequent event) In Millions, unless otherwise specified	Oct. 03, 2012 AES IC Ictas JV [Member] XAF	Oct. 05, 2012 Tisza II [Member] USD ($)
Subsequent Event [Line Items]
Ownership interest in hydro projects	100.00%
Net Proceeds From Joint Venture Split	10
Gain on Joint Venture Split	11
Proceeds To Be Received From Joint Venture Split	85
Ownership Interest Percent To Be Sold	50.40%
Sale price of asset group		17
Carrying amount of asset group		35
Cumulative translation losses excluded from carrying amount		73
Estimated pretax loss on sale of asset group		$ 91