v2.4.0.6

Debt (Textuals 2) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011	Dec. 31, 2011
Debt Instrument [Line Items]
Power generation capacity	11,392		11,391
Letters of credit issued	$ 550		$ 581
Long-term Debt	10,495		10,425
Debt extinguishment costs	(12)	(93)
Russell City Project [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	845
Power generation capacity	619
Construction Loan Facility	700
Project Letter of Credit Facility	77
Debt Service Letter of Credit Facility	68
Term Loan Period	10
Applicable Margin Range Percentage Above British Bankers' Association Interest Settlement Rates	2.25%
Amount Drawn Under Construction Loan	334
Letters of credit issued	61
Equity Method Investment, Ownership Percentage	75.00%
Minority Interest Ownership Percentage By Noncontrolling Third Party Owners	25.00%
Los Esteros Project [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	373
Power generation capacity	188
Power generation capacity after upgrade	309
Construction Loan Facility	305
Project Letter of Credit Facility	38
Debt Service Letter of Credit Facility	30
Term Loan Period	10
Applicable Margin Range Percentage Above British Bankers' Association Interest Settlement Rates	2.25%
Amount Drawn Under Construction Loan	107
Letters of credit issued	$ 30

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Construction Loan Facility

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Debt Service Letter of Credit Facility

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Letters of credit issued

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Minority Interest Ownership Percentage By Noncontrolling Third Party Owners

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Power generation capacity

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Power generation capacity after upgrade

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Project Letter of Credit Facility

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Term Loan Period

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The stated principal amount of the debt instrument at time of issuance, which may vary from the carrying amount because of unamortized premium or discount.

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-Publisher AICPA

-Name Accounting Principles Board Opinion (APB)

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Amount represents the difference between the fair value of the payments made and the carrying amount of the debt at the time of its extinguishment.

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Including current and noncurrent portions, aggregate carrying amount of long-term borrowings as of the balance sheet date. May include notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, which had initial maturities beyond one year or beyond the normal operating cycle, if longer, and after deducting unamortized discount or premiums, if any.

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