Debt (Details) (USD $) In Millions, unless otherwise specified	Jun. 30, 2012
Nonrecourse Debt Default [Line Items]
Default	$ 1,413
Sonel [Member]
Nonrecourse Debt Default [Line Items]
Net Assets	288
Kelanitissa [Member]
Nonrecourse Debt Default [Line Items]
Net Assets	48
Maritza [Member]
Nonrecourse Debt Default [Line Items]
Net Assets	231
Saurashtra [Member]
Nonrecourse Debt Default [Line Items]
Net Assets	15
Kribi [Member]
Nonrecourse Debt Default [Line Items]
Net Assets	(11)
Dibamba [Member]
Nonrecourse Debt Default [Line Items]
Net Assets	36
Covenant Violation [Member] | Sonel [Member]
Nonrecourse Debt Default [Line Items]
Default	302
Covenant Violation [Member] | Kelanitissa [Member]
Nonrecourse Debt Default [Line Items]
Default	10
Covenant Violation [Member] | Maritza [Member]
Nonrecourse Debt Default [Line Items]
Default	861
Covenant Violation [Member] | Saurashtra [Member]
Nonrecourse Debt Default [Line Items]
Default	26
Covenant Violation [Member] | Dibamba [Member]
Nonrecourse Debt Default [Line Items]
Default	77
Payment Default [Member] | Kribi [Member]
Nonrecourse Debt Default [Line Items]
Default	$ 137