2.2.0.7 true RECENTLY ISSUED ACCOUNTING STANDARDS, NOT YET ADOPTED 111 - Disclosure - RECENTLY ISSUED ACCOUNTING STANDARDS, NOT YET ADOPTED true false false false 1 USD true false false false PEPCO HOLDINGS INC dei_LegalEntityAxis xbrldi http://xbrl.org/2006/xbrldi us-gaap_ParentCompanyMember dei_LegalEntityAxis explicitMember iso4217_USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 iso4217_USD_per_shares Divide http://www.xbrl.org/2003/iso4217 USD iso4217 http://www.xbrl.org/2003/instance shares 0 shares Standard http://www.xbrl.org/2003/instance shares 0 $ 1 PEPCO HOLDINGS INC 0 na true na na No definition available. false true false false false false false false false false false http://www.pepcoholdings.com/taxonomy/role/notestofinancialstatementsdescriptionofnewaccountingpronouncementsnotyetadoptedtextblock false 1 false false false false 0 0 false false false false 1 USD true false false false PEPCO HOLDINGS INC dei_LegalEntityAxis xbrldi http://xbrl.org/2006/xbrldi us-gaap_ParentCompanyMember dei_LegalEntityAxis explicitMember iso4217_USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 iso4217_USD_per_shares Divide http://www.xbrl.org/2003/iso4217 USD iso4217 http://www.xbrl.org/2003/instance shares 0 shares Standard http://www.xbrl.org/2003/instance shares 0 $ na No definition available. No authoritative reference available. false 2 RECENTLY ISSUED ACCOUNTING STANDARDS, NOT YET ADOPTED 2 pom_DescriptionOfNewAccountingPronouncementsNotYetAdoptedTextBlock pom false na duration For a new accounting pronouncement that has been issued but not yet adopted, an entity's disclosure should (1) describe the... false false false false false false false false false false false false 1 false false false false 0 0 <div> (4) RECENTLY ISSUED ACCOUNTING STANDARDS, NOT YET ADOPTED Fair Value Measurements and Disclosures (ASC 820) The new FASB disclosure requirements that will be effective beginning with PHI’s March 31, 2011 financial statements require that the items within the reconciliation of the Level 3 valuation category be presented in separate categories for purchases, sales, issuances, and settlements, if significant. PHI is evaluating the impact of this part of the guidance on its financial statements. Receivables (ASC 310) The new FASB disclosure requirements relating to an entity’s exposure to credit losses from financing receivables will be effective beginning with PHI’s December 31, 2010 financial statements. The new guidance requires disclosures about the credit quality of receivables with maturities of greater than one year and related accounting policies. PHI is evaluating the impact of this new requirement on the disclosures related to its financial statements. </div> false false false us-types:textBlockItemType textblock For a new accounting pronouncement that has been issued but not yet adopted, an entity's disclosure should (1) describe the new pronouncement, the date that adoption is required and the date that the entity plans to adopt, if earlier; (2) discuss the methods of adoption allowed by the pronouncement and the method expected to be utilized by the entity, if determined; (3) discuss the impact that adoption of the pronouncement is expected to have on the financial statements of the entity, unless such impact is not known or reasonably estimable (in which case, a statement to that effect should be made) and; (4) disclose the potential impact of other significant matters that the entity believes might result from the adoption of the pronouncement (for example, technical violations of debt covenant agreements and planned or intended changes in business practices.) No authoritative reference available. false 3 ATLANTIC CITY ELECTRIC CO 0 na true na na No definition available. false true false false false false false false false false false http://www.pepcoholdings.com/taxonomy/role/notestofinancialstatementsdescriptionofnewaccountingpronouncementsnotyetadoptedtextblock false 1 false false false false 0 0 false false false false 2 USD true false false false ATLANTIC CITY ELECTRIC CO dei_LegalEntityAxis xbrldi http://xbrl.org/2006/xbrldi pom_AtlanticCityElectricCoMember dei_LegalEntityAxis explicitMember iso4217_USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 $ na No definition available. No authoritative reference available. false 4 RECENTLY ISSUED ACCOUNTING STANDARDS, NOT YET ADOPTED 2 pom_DescriptionOfNewAccountingPronouncementsNotYetAdoptedTextBlock pom false na duration For a new accounting pronouncement that has been issued but not yet adopted, an entity's disclosure should (1) describe the... false false false false false false false false false false false false 1 false false false false 0 0 <div> (4) RECENTLY ISSUED ACCOUNTING STANDARDS, NOT YET ADOPTED Fair Value Measurements and Disclosures (ASC 820) The new FASB disclosure requirements that will be effective beginning with ACE’s March 31, 2011 financial statements require that the items within the reconciliation of the Level 3 valuation category be presented in separate categories for purchases, sales, issuances, and settlements, if significant. ACE is evaluating the impact of this part of the guidance on its financial statements. </div> false false false us-types:textBlockItemType textblock For a new accounting pronouncement that has been issued but not yet adopted, an entity's disclosure should (1) describe the new pronouncement, the date that adoption is required and the date that the entity plans to adopt, if earlier; (2) discuss the methods of adoption allowed by the pronouncement and the method expected to be utilized by the entity, if determined; (3) discuss the impact that adoption of the pronouncement is expected to have on the financial statements of the entity, unless such impact is not known or reasonably estimable (in which case, a statement to that effect should be made) and; (4) disclose the potential impact of other significant matters that the entity believes might result from the adoption of the pronouncement (for example, technical violations of debt covenant agreements and planned or intended changes in business practices.) No authoritative reference available. false 5 DELMARVA POWER & LIGHT CO /DE/ 0 na true na na No definition available. false true false false false false false false false false false http://www.pepcoholdings.com/taxonomy/role/notestofinancialstatementsdescriptionofnewaccountingpronouncementsnotyetadoptedtextblock false 1 false false false false 0 0 false false false false 3 USD true false false false DELMARVA POWER & LIGHT CO /DE/ dei_LegalEntityAxis xbrldi http://xbrl.org/2006/xbrldi pom_DelmarvaPowerLightCoMember dei_LegalEntityAxis explicitMember iso4217_USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 $ na No definition available. No authoritative reference available. false 6 RECENTLY ISSUED ACCOUNTING STANDARDS, NOT YET ADOPTED 2 pom_DescriptionOfNewAccountingPronouncementsNotYetAdoptedTextBlock pom false na duration For a new accounting pronouncement that has been issued but not yet adopted, an entity's disclosure should (1) describe the... false false false false false false false false false false false false 1 false false false false 0 0 <div> (4) RECENTLY ISSUED ACCOUNTING STANDARDS, NOT YET ADOPTED Fair Value Measurements and Disclosures (ASC 820) The new FASB disclosure requirements that will be effective beginning with DPL’s March 31, 2011 financial statements require that the items within the reconciliation of the Level 3 valuation category be presented in separate categories for purchases, sales, issuances, and settlements, if significant. DPL is evaluating the impact of this part of the guidance on its financial statements. </div> false false false us-types:textBlockItemType textblock For a new accounting pronouncement that has been issued but not yet adopted, an entity's disclosure should (1) describe the new pronouncement, the date that adoption is required and the date that the entity plans to adopt, if earlier; (2) discuss the methods of adoption allowed by the pronouncement and the method expected to be utilized by the entity, if determined; (3) discuss the impact that adoption of the pronouncement is expected to have on the financial statements of the entity, unless such impact is not known or reasonably estimable (in which case, a statement to that effect should be made) and; (4) disclose the potential impact of other significant matters that the entity believes might result from the adoption of the pronouncement (for example, technical violations of debt covenant agreements and planned or intended changes in business practices.) No authoritative reference available. false 7 POTOMAC ELECTRIC POWER CO 0 na true na na No definition available. false true false false false false false false false false false http://www.pepcoholdings.com/taxonomy/role/notestofinancialstatementsdescriptionofnewaccountingpronouncementsnotyetadoptedtextblock false 1 false false false false 0 0 false false false false 4 USD true false false false POTOMAC ELECTRIC POWER CO dei_LegalEntityAxis xbrldi http://xbrl.org/2006/xbrldi pom_PotomacElectricPowerCoMember dei_LegalEntityAxis explicitMember iso4217_USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 $ na No definition available. No authoritative reference available. false 8 RECENTLY ISSUED ACCOUNTING STANDARDS, NOT YET ADOPTED 2 pom_DescriptionOfNewAccountingPronouncementsNotYetAdoptedTextBlock pom false na duration For a new accounting pronouncement that has been issued but not yet adopted, an entity's disclosure should (1) describe the... false false false false false false false false false false false false 1 false false false false 0 0 <div> (4) RECENTLY ISSUED ACCOUNTING STANDARDS, NOT YET ADOPTED Fair Value Measurements and Disclosures (ASC 820) The new FASB disclosure requirements that will be effective beginning with Pepco’s March 31, 2011 financial statements require that the items within the reconciliation of the Level 3 valuation category be presented in separate categories for purchases, sales, issuances, and settlements, if significant. Pepco is evaluating the impact of this part of the guidance on its financial statements. </div> false false false us-types:textBlockItemType textblock For a new accounting pronouncement that has been issued but not yet adopted, an entity's disclosure should (1) describe the new pronouncement, the date that adoption is required and the date that the entity plans to adopt, if earlier; (2) discuss the methods of adoption allowed by the pronouncement and the method expected to be utilized by the entity, if determined; (3) discuss the impact that adoption of the pronouncement is expected to have on the financial statements of the entity, unless such impact is not known or reasonably estimable (in which case, a statement to that effect should be made) and; (4) disclose the potential impact of other significant matters that the entity believes might result from the adoption of the pronouncement (for example, technical violations of debt covenant agreements and planned or intended changes in business practices.) No authoritative reference available. false 1 8 false UnKnown UnKnown UnKnown false true