2.2.0.7 true Financial Instruments' Carrying Amounts and Fair Values (Detail) (USD $) 156 - Disclosure - Financial Instruments' Carrying Amounts and Fair Values (Detail) true false In Millions false false 1 USD false false iso4217_USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 shares Standard http://www.xbrl.org/2003/instance shares 0 $ false 2 USD false false iso4217_USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 shares Standard http://www.xbrl.org/2003/instance shares 0 $ 3 Junior subordinated notes payable to affiliates 2 d_SubordinatedDebtLongTermAffiliates d false credit instant Affiliated portion of collateralized/uncollateralized debt obligations due beyond one year/operating cycle. Subordinated debt... false false false false false false false false false false false false 1 true true false false 268000000 268 false false false 2 true true false false 268000000 268 [1] false false false xbrli:monetaryItemType monetary Affiliated portion of collateralized/uncollateralized debt obligations due beyond one year/operating cycle. Subordinated debt places a lender in a lien position behind the primary lender of the company. No authoritative reference available. false 4 Enhanced junior subordinated notes 2 us-gaap_SubordinatedLongTermDebt us-gaap true credit instant No definition available. false false false false false false false false false false false false 1 false true false false 1467000000 1467 false false false 2 false true false false 1483000000 1483 [1] false false false xbrli:monetaryItemType monetary Carrying value as of the balance sheet date of collateralized/uncollateralized debt obligation (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion. Subordinated debt places a lender in a lien position behind the primary lender of the company. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 22 -Article 5 false 5 Subsidiary preferred stock 2 us-gaap_PreferredStockValueOutstanding us-gaap true credit instant No definition available. false false false false false false false false false false false false 1 false true false false 257000000 257 false false false 2 false true false false 257000000 257 [1] false false false xbrli:monetaryItemType monetary Value of all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by shareholders, which is net of related treasury stock. May be all or a portion of the number of preferred shares authorized. These shares represent the ownership interest of the preferred shareholders. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 29 -Article 5 false 6 Carrying (Reported) Amount, Fair Value Disclosure 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/disclosurefinancialinstrumentscarryingamountsandfairvalues false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false false 3 USD true false false false Carrying (Reported) Amount, Fair Value Disclosure us-gaap_FairValueByBalanceSheetGroupingDisclosureItemAmountsAxis xbrldi http://xbrl.org/2006/xbrldi us-gaap_CarryingReportedAmountFairValueDisclosureMember us-gaap_FairValueByBalanceSheetGroupingDisclosureItemAmountsAxis explicitMember iso4217_USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 $ false 4 USD true false false false Carrying (Reported) Amount, Fair Value Disclosure us-gaap_FairValueByBalanceSheetGroupingDisclosureItemAmountsAxis xbrldi http://xbrl.org/2006/xbrldi us-gaap_CarryingReportedAmountFairValueDisclosureMember us-gaap_FairValueByBalanceSheetGroupingDisclosureItemAmountsAxis explicitMember iso4217_USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 $ na No definition available. No authoritative reference available. false 7 Long-term debt, including securities due within one year 2 us-gaap_LongTermDebt us-gaap true credit instant No definition available. false false false false false false false false false false false false 1 false true false false 15064000000 15064 [2] false false false 2 false true false false 14867000000 14867 [2] false false false xbrli:monetaryItemType monetary 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. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 16 -Article 7 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 16 -Article 9 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 20, 22 -Article 5 false 8 Junior subordinated notes payable to affiliates 2 d_SubordinatedDebtLongTermAffiliates d false credit instant Affiliated portion of collateralized/uncollateralized debt obligations due beyond one year/operating cycle. Subordinated debt... false false false false false false false false false false false false 1 false true false false 268000000 268 false false false 2 false true false false 268000000 268 false false false xbrli:monetaryItemType monetary Affiliated portion of collateralized/uncollateralized debt obligations due beyond one year/operating cycle. Subordinated debt places a lender in a lien position behind the primary lender of the company. No authoritative reference available. false 9 Enhanced junior subordinated notes 2 us-gaap_SubordinatedLongTermDebt us-gaap true credit instant No definition available. false false false false false false false false false false false false 1 false true false false 1467000000 1467 false false false 2 false true false false 1483000000 1483 false false false xbrli:monetaryItemType monetary Carrying value as of the balance sheet date of collateralized/uncollateralized debt obligation (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion. Subordinated debt places a lender in a lien position behind the primary lender of the company. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 22 -Article 5 false 10 Subsidiary preferred stock 2 us-gaap_PreferredStockValueOutstanding us-gaap true credit instant No definition available. false false false false false false false false false false false false 1 false true false false 257000000 257 [3] false false false 2 false true false false 257000000 257 [3] false false false xbrli:monetaryItemType monetary Value of all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by shareholders, which is net of related treasury stock. May be all or a portion of the number of preferred shares authorized. These shares represent the ownership interest of the preferred shareholders. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 29 -Article 5 false 11 Estimate of Fair Value, Fair Value Disclosure 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/disclosurefinancialinstrumentscarryingamountsandfairvalues false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false false 5 USD true false false false Estimate of Fair Value, Fair Value Disclosure us-gaap_FairValueByBalanceSheetGroupingDisclosureItemAmountsAxis xbrldi http://xbrl.org/2006/xbrldi us-gaap_EstimateOfFairValueFairValueDisclosureMember us-gaap_FairValueByBalanceSheetGroupingDisclosureItemAmountsAxis explicitMember iso4217_USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 $ false 6 USD true false false false Estimate of Fair Value, Fair Value Disclosure us-gaap_FairValueByBalanceSheetGroupingDisclosureItemAmountsAxis xbrldi http://xbrl.org/2006/xbrldi us-gaap_EstimateOfFairValueFairValueDisclosureMember us-gaap_FairValueByBalanceSheetGroupingDisclosureItemAmountsAxis explicitMember iso4217_USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 $ na No definition available. No authoritative reference available. false 12 Long-term debt, including securities due within one year 2 us-gaap_LongTermDebt us-gaap true credit instant No definition available. false false false false false false false false false false false false 1 false true false false 17352000000 17352 [2],[4] false false false 2 false true false false 15970000000 15970 [2],[4] false false false xbrli:monetaryItemType monetary 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. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 16 -Article 7 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 16 -Article 9 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 20, 22 -Article 5 false 13 Junior subordinated notes payable to affiliates 2 d_SubordinatedDebtLongTermAffiliates d false credit instant Affiliated portion of collateralized/uncollateralized debt obligations due beyond one year/operating cycle. Subordinated debt... false false false false false false false false false false false false 1 false true false false 265000000 265 [4] false false false 2 false true false false 255000000 255 [4] false false false xbrli:monetaryItemType monetary Affiliated portion of collateralized/uncollateralized debt obligations due beyond one year/operating cycle. Subordinated debt places a lender in a lien position behind the primary lender of the company. No authoritative reference available. false 14 Enhanced junior subordinated notes 2 us-gaap_SubordinatedLongTermDebt us-gaap true credit instant No definition available. false false false false false false false false false false false false 1 false true false false 1573000000 1573 [4] false false false 2 false true false false 1487000000 1487 [4] false false false xbrli:monetaryItemType monetary Carrying value as of the balance sheet date of collateralized/uncollateralized debt obligation (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion. Subordinated debt places a lender in a lien position behind the primary lender of the company. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 22 -Article 5 false 15 Subsidiary preferred stock 2 us-gaap_PreferredStockValueOutstanding us-gaap true credit instant No definition available. false false false false false false false false false false false false 1 true true false false 252000000 252 [3],[4] false false false 2 true true false false 251000000 251 [3],[4] false false false xbrli:monetaryItemType monetary Value of all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by shareholders, which is net of related treasury stock. May be all or a portion of the number of preferred shares authorized. These shares represent the ownership interest of the preferred shareholders. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 29 -Article 5 false 1 Dominion's Consolidated Balance Sheet at December 31, 2009 has been derived from the audited Consolidated Financial Statements at that date. 2 Includes amounts which represent the unamortized discount and premium. At September 30, 2010 and December 31, 2009, includes the valuation of certain fair value hedges associated with Dominion's fixed rate debt of approximately $59 million and $23 million, respectively. 3 Includes issuance expenses of $2 million at September 30, 2010 and December 31, 2009. 4 Fair value is estimated using market prices, where available, and interest rates currently available for issuance of debt with similar terms and remaining maturities. The carrying amount of debt issues with short-term maturities and variable rates refinanced at current market rates is a reasonable estimate of their fair value. 2 13 false Millions UnKnown UnKnown false true