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Includes long-term advances receivable form a party that is affiliated with the reporting entity by means of direct or indirect ownership. No authoritative reference available. false 11 2 us-gaap_DecommissioningFundInvestments us-gaap true debit instant No definition available. false false false false false false false false false false false terselabel false 1 false true false false 1884000000 1884 false false false 2 false true false false 1765000000 1765 false false false xbrli:monetaryItemType monetary Decommission fund to pay for the costs of decontaminating and decommissioning of facilities through collection of revenues derived from utility assessments and government appropriations. Decommission fund investment for the process whereby a power station, at the end of its economic life, is taken permanently out of service and its site made available for other purposes. In the case of a nuclear station this comprises three different states of clearance. 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It also includes other kinds of accounts that have the general characteristics of demand deposits in that the Entity may deposit additional funds at any time and also effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months. 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No authoritative reference available. true 162 2 us-gaap_CommitmentsAndContingencies2009 us-gaap true na duration No definition available. false false false false false false false false false false false false 1 false false false false 0 0   false false false 2 false false false false 0 0   false false false xbrli:stringItemType string Represents the caption on the face of the balance sheet to indicate that the entity has entered into (1) purchase or supply arrangements that will require expending a portion of its resources to meet the terms thereof, and (2) is exposed to potential losses or, less frequently, gains, arising from (a) possible claims against a company's resources due to future performance under contract terms, and (b) possible losses or likely gains from uncertainties that will ultimately be resolved when one or more future events that are deemed likely to occur do occur or fail to occur. 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May be called contributed capital, capital in excess of par, capital surplus, or paid-in capital. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 31 -Article 5 false 166 2 us-gaap_RetainedEarningsAccumulatedDeficit us-gaap true credit instant No definition available. false false false false false false false false false false false verboselabel false 1 false true false false -858000000 -858 false false false 2 false true false false -405000000 -405 false false false xbrli:monetaryItemType monetary The cumulative amount of the reporting entity's undistributed earnings or deficit. 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It also includes other kinds of accounts that have the general characteristics of demand deposits in that the Entity may deposit additional funds at any time and also effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months. 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