Baltimore Gas and Electric Company [Member] Baltimore Gas and Electric Company [Member] Entity Incorporation, State or Country Code Entity Incorporation, State or Country Code Document Information, Document [Axis] Document Information, Document [Axis] Geographical [Axis] Geographical [Axis] Security Exchange Name Security Exchange Name Document [Domain] Document [Domain] Potomac Electric Power Company [Member] Potomac Electric Power Company [Member] Potomac Electric Power Company [Member] Entity Address, City or Town Entity Address, City or Town PECO Energy Co [Member] PECO Energy Co [Member] PECO Energy Co [Member] Soliciting Material Soliciting Material Cover page. Cover [Abstract] VIRGINIA VIRGINIA Legal Entity [Axis] Legal Entity [Axis] City Area Code City Area Code Amendment Flag Amendment Flag Entity Tax Identification Number Entity Tax Identification Number Trading Symbol Trading Symbol Entity Registrant Name Entity Registrant Name Pre-commencement Tender Offer Pre-commencement Tender Offer Entity Emerging Growth Company Entity Emerging Growth Company Delmarva Power and Light Company [Member] Delmarva Power and Light Company [Member] Delmarva Power and Light Company [Member] Entity Central Index Key Entity Central Index Key Entity File Number Entity File Number Entity Address, State or Province Entity Address, State or Province Geographical [Domain] Geographical [Domain] Pre-commencement Issuer Tender Offer Pre-commencement Issuer Tender Offer Pepco Holdings LLC [Member] Pepco Holdings LLC [Member] Pepco Holdings LLC [Member] Commonwealth Edison Co [Member] Commonwealth Edison Co [Member] Commonwealth Edison Co [Member] Entity Address, Address Line One Entity Address, Address Line One Document Information [Line Items] Document Information [Line Items] Document Information [Table] Document Information [Table] Entity Address, Postal Zip Code Entity Address, Postal Zip Code Written Communications Written Communications Entity Address, Address Line Two Entity Address, Address Line Two Local Phone Number Local Phone Number Entity [Domain] Entity [Domain] Title of 12(b) Security Title of 12(b) Security Document Period End Date Document Period End Date Document Type Document Type DELAWARE DELAWARE Atlantic City Electric Company [Member] Atlantic City Electric Company [Member] Atlantic City Electric Company [Member] DISTRICT OF COLUMBIA DISTRICT OF COLUMBIA