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Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 12 -Article 5 true 36 Other Investments 0 na true na na No definition available. false true false false false false false false false false false http://www.dom.com/taxonomy/role/disclosuremarketableequityanddebtsecuritiesandcashequivalentsclassifiedasavailableforsaleandcostmethodinvestmentsindecommissioningtrustfunds false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false false 15 USD true false false false Other Investments us-gaap_ScheduleOfTradingSecuritiesAndOtherTradingAssetsMajorTypesOfTradingSecuritiesAndAssetsAxis xbrldi http://xbrl.org/2006/xbrldi d_OtherInvestmentsMember us-gaap_ScheduleOfTradingSecuritiesAndOtherTradingAssetsMajorTypesOfTradingSecuritiesAndAssetsAxis explicitMember iso4217_USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 $ false 16 USD true false false false Other Investments us-gaap_ScheduleOfTradingSecuritiesAndOtherTradingAssetsMajorTypesOfTradingSecuritiesAndAssetsAxis xbrldi http://xbrl.org/2006/xbrldi d_OtherInvestmentsMember us-gaap_ScheduleOfTradingSecuritiesAndOtherTradingAssetsMajorTypesOfTradingSecuritiesAndAssetsAxis explicitMember iso4217_USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 $ na No definition available. No authoritative reference available. false 37 Amortized Cost 2 us-gaap_AvailableForSaleSecuritiesAmortizedCost us-gaap true debit instant No definition available. false false false false false false false false false false false false 1 false true false false 47000000 47 [4] false false false 2 false true false false 60000000 60 [4] false false false xbrli:monetaryItemType monetary This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments made for accretion, amortization, other-than-temporary impairments, and hedging, if any. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name FASB Staff Position (FSP) -Number FAS115-1/124-1 -Paragraph 7 -Footnote 2 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 19 false 40 Fair Value 2 us-gaap_DecommissioningFundInvestments us-gaap true debit instant No definition available. false false false false false false false false false false false totallabel false 1 true true false false 47000000 47 [4] false false false 2 true true false false 60000000 60 [4] 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. Immediately after the final closure, radioactive material such as nuclear fuel and operational waste is removed and the buildings surrounding the reactor shield are dismantled and finally the reactor itself is dismantled. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 12 -Article 5 true 1 Included in AOCI and the decommissioning trust regulatory liability. 2 The fair value of securities in an unrealized loss position was $88 million and $169 million at September 30, 2010 and December 31, 2009, respectively. 3 Dominion's Consolidated Balance Sheet at December 31, 2009 has been derived from the audited Consolidated Financial Statements at that date. 4 At September 30, 2010 and December 31, 2009, reflects $57 million and $11 million, respectively, related to net pending sales and purchases of securities. 2 33 false Millions UnKnown UnKnown false true