2.2.0.25truefalse10401 - Disclosure - RECENTLY ISSUED ACCOUNTING STANDARDS, NOT YET ADOPTEDtruefalsefalse1falsefalseUSDtruefalse{dei_LegalEntityAxis} : PEPCO HOLDINGS INC 1/1/2010 - 12/31/2010 USD ($) USD ($) / shares $Duration_1_1_2010_To_12_31_20105http://www.sec.gov/CIK0001135971duration2010-01-01T00:00:002010-12-31T00:00:00falsefalsePEPCO HOLDINGS INCdei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ParentCompanyMemberdei_LegalEntityAxisexplicitMemberUnit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170Unit1Standardhttp://www.xbrl.org/2003/instancesharesxbrli0Unit13Dividehttp://www.xbrl.org/2003/iso4217USDiso4217http://www.xbrl.org/2003/instancesharesxbrli0USDUSD$1false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://www.pepcoholdings.com/taxonomy/role/disclosurerecentlyissuedaccountingstandardsnotyetadopted1falsefalsefalse00falsefalsefalsefalsefalse1falsefalseUSDtruefalse{dei_LegalEntityAxis} : PEPCO HOLDINGS INC 1/1/2010 - 12/31/2010 USD ($) USD ($) / shares $Duration_1_1_2010_To_12_31_20105http://www.sec.gov/CIK0001135971duration2010-01-01T00:00:002010-12-31T00:00:00falsefalsePEPCO HOLDINGS INCdei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ParentCompanyMemberdei_LegalEntityAxisexplicitMemberUnit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170Unit1Standardhttp://www.xbrl.org/2003/instancesharesxbrli0Unit13Dividehttp://www.xbrl.org/2003/iso4217USDiso4217http://www.xbrl.org/2003/instancesharesxbrli0USDUSD$OthernaNo definition available.No authoritative reference available.falsefalsePEPCO HOLDINGS INC2false0pom_DescriptionOfNewAccountingPronouncementsNotYetAdoptedTextBlockpomfalsenadurationFor a new accounting pronouncement that has been issued but not yet adopted, an entity's disclosure should (1) describe the...falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1falsefalsefalse00<div> (4) RECENTLY ISSUED ACCOUNTING STANDARDS, NOT YET ADOPTED Fair Value Measurement and Disclosures (ASC 820) The FASB issued new disclosure requirements that require the disaggregation of the Level 3 fair value measurement reconciliations into separate categories for significant purchases, sales, issuances, and settlements. This requirement is effective beginning with PHI's March 31, 2011 financial statements. PHI is evaluating the impact of this new guidance on its financial statement footnote disclosures. Revenue Recognition (ASC 605) The FASB has issued new revenue recognition guidance related to the determination of separate units of accounting for multiple-deliverables within a single contract. PHI's revenues potentially affected by this guidance are primarily those of Pepco Energy Services' energy services business, which enters into contracts that have multiple deliverables, such as design, installation, operation and maintenance, measurement, and verification. The guidance is effective January 1, 2011 for PHI, and it is not expected to have a material impact on Pepco Energy Services' revenue recognition methods or results. Goodwill (ASC 350) In December 2010, the FASB issued new guidance on performing goodwill impairment tests. The new guidance eliminates the option to exclude liabilities that are part of the capital structure of the reporting unit when calculating the carrying value of the reporting unit. This is effective for PHI beginning January 1, 2011. Under the new guidance, the carrying value of the reporting unit is the net amount of the assets and liabilities allocated to the reporting unit. PHI allocates liabilities to the reporting unit when performing its goodwill impairment test, so the new guidance is not expected to change how PHI currently performs its goodwill impairment test. </div>falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringFor 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.falsefalseRECENTLY ISSUED ACCOUNTING STANDARDS, NOT YET ADOPTED3false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://www.pepcoholdings.com/taxonomy/role/disclosurerecentlyissuedaccountingstandardsnotyetadopted1falsefalsefalse00falsefalsefalsefalsefalse2falsefalseUSDtruefalse{dei_LegalEntityAxis} : POTOMAC ELECTRIC POWER CO 1/1/2010 - 12/31/2010 USD ($) $Duration_1_1_2010_To_12_31_20104http://www.sec.gov/CIK0001135971duration2010-01-01T00:00:002010-12-31T00:00:00falsefalsePOTOMAC ELECTRIC POWER COdei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldipom_PotomacElectricPowerCoMemberdei_LegalEntityAxisexplicitMemberUnit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$OthernaNo definition available.No authoritative reference available.falsefalsePOTOMAC ELECTRIC POWER CO4false0pom_DescriptionOfNewAccountingPronouncementsNotYetAdoptedTextBlockpomfalsenadurationFor a new accounting pronouncement that has been issued but not yet adopted, an entity's disclosure should (1) describe the...falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1falsefalsefalse00<div> (4) RECENTLY ISSUED ACCOUNTING STANDARDS, NOT YET ADOPTED Fair Value Measurement and Disclosures (ASC 820) The FASB issued new disclosure requirements that require the disaggregation of the Level 3 fair value measurement reconciliations into separate categories for significant purchases, sales, issuances, and settlements. This requirement is effective beginning with Pepco's March 31, 2011 financial statements. Pepco is evaluating the impact of this new guidance on its financial statement footnote disclosures. </div>falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringFor 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.falsefalseRECENTLY ISSUED ACCOUNTING STANDARDS, NOT YET ADOPTED5false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://www.pepcoholdings.com/taxonomy/role/disclosurerecentlyissuedaccountingstandardsnotyetadopted1falsefalsefalse00falsefalsefalsefalsefalse3falsefalseUSDtruefalse{dei_LegalEntityAxis} : DELMARVA POWER & LIGHT CO /DE/ 1/1/2010 - 12/31/2010 USD ($) $Duration_1_1_2010_To_12_31_20103http://www.sec.gov/CIK0001135971duration2010-01-01T00:00:002010-12-31T00:00:00falsefalseDELMARVA POWER & LIGHT CO /DE/dei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldipom_DelmarvaPowerLightCoMemberdei_LegalEntityAxisexplicitMemberUnit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$OthernaNo definition available.No authoritative reference available.falsefalseDELMARVA POWER & LIGHT CO /DE/6false0pom_DescriptionOfNewAccountingPronouncementsNotYetAdoptedTextBlockpomfalsenadurationFor a new accounting pronouncement that has been issued but not yet adopted, an entity's disclosure should (1) describe the...falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1falsefalsefalse00<div> (4) RECENTLY ISSUED ACCOUNTING STANDARDS, NOT YET ADOPTED Fair Value Measurement and Disclosures (ASC 820) The FASB issued new disclosure requirements that require the disaggregation of the Level 3 fair value measurement reconciliations into separate categories for significant purchases, sales, issuances, and settlements. This requirement is effective beginning with DPL's March 31, 2011 financial statements. DPL is evaluating the impact of this new guidance on its financial statement footnote disclosures.   Goodwill (ASC 350) In December 2010, the FASB issued new guidance on performing goodwill impairment tests. The new guidance eliminates the option to exclude liabilities that are part of the capital structure of the reporting unit when calculating the carrying value of the reporting unit. This is effective for DPL beginning January 1, 2011. Under the new guidance, the carrying value of the reporting unit is the net amount of the assets and liabilities allocated to the reporting unit. DPL allocates liabilities to the reporting unit when performing its goodwill impairment test, so the new guidance is not expected to change how DPL currently performs its goodwill impairment test. </div>falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringFor 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.falsefalseRECENTLY ISSUED ACCOUNTING STANDARDS, NOT YET ADOPTED7false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://www.pepcoholdings.com/taxonomy/role/disclosurerecentlyissuedaccountingstandardsnotyetadopted1falsefalsefalse00falsefalsefalsefalsefalse4falsefalseUSDtruefalse{dei_LegalEntityAxis} : ATLANTIC CITY ELECTRIC CO 1/1/2010 - 12/31/2010 USD ($) $Duration_1_1_2010_To_12_31_20102http://www.sec.gov/CIK0001135971duration2010-01-01T00:00:002010-12-31T00:00:00falsefalseATLANTIC CITY ELECTRIC COdei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldipom_AtlanticCityElectricCoMemberdei_LegalEntityAxisexplicitMemberUnit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$OthernaNo definition available.No authoritative reference available.falsefalseATLANTIC CITY ELECTRIC CO8false0pom_DescriptionOfNewAccountingPronouncementsNotYetAdoptedTextBlockpomfalsenadurationFor a new accounting pronouncement that has been issued but not yet adopted, an entity's disclosure should (1) describe the...falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1falsefalsefalse00<div> (4) RECENTLY ISSUED ACCOUNTING STANDARDS, NOT YET ADOPTED Fair Value Measurement and Disclosures (ASC 820) The FASB issued new disclosure requirements that require the disaggregation of the Level 3 fair value measurement reconciliations into separate categories for significant purchases, sales, issuances, and settlements. This requirement is effective beginning with ACE's March 31, 2011 financial statements. ACE is evaluating the impact of this new guidance on its financial statement footnote disclosures. </div>falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringFor 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.falsefalseRECENTLY ISSUED ACCOUNTING STANDARDS, NOT YET ADOPTED18RECENTLY ISSUED ACCOUNTING STANDARDS, NOT YET ADOPTEDUnKnownUnKnownUnKnownUnKnownfalsetrue