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Severance Severance - PHI Merger (Details) - PHI Merger [Member] $ in Millions | 12 Months Ended
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Dec. 31, 2016 USD ($)
Restructuring Cost and Reserve [Line Items] |
Severance Costs | $ 57
Exelon Generation Co L L C [Member] |
Restructuring Cost and Reserve [Line Items] |
Severance Costs | 9
Commonwealth Edison Co [Member] |
Restructuring Cost and Reserve [Line Items] |
Severance Costs | 2
PECO Energy Co [Member] |
Restructuring Cost and Reserve [Line Items] |
Severance Costs | 1
Baltimore Gas and Electric Company [Member] |
Restructuring Cost and Reserve [Line Items] |
Severance Costs | 1
Pepco Holdings LLC [Member] | Successor [Member] |
Restructuring Cost and Reserve [Line Items] |
Severance Costs | 44
Potomac Electric Power Company [Member] |
Restructuring Cost and Reserve [Line Items] |
Severance Costs | 21
Delmarva Power & Light Company [Member] |
Restructuring Cost and Reserve [Line Items] |
Severance Costs | 13
Atlantic City Electric Company [Member] |
Restructuring Cost and Reserve [Line Items] |
Severance Costs | $ 10

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- Definition Amount of expenses for special or contractual termination benefits provided to current employees involuntarily terminated under a benefit arrangement associated exit or disposal activities pursuant to an authorized plan. Excludes expenses related to one-time termination benefits, a discontinued operation or an asset retirement obligation. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 420 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SAB Topic 5.P.4(b)) -URI http://asc.fasb.org/extlink&oid=27011515&loc=d3e140904-122747 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 420 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 420 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 5.P.3) -URI http://asc.fasb.org/extlink&oid=27011515&loc=d3e140864-122747 + Details
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