New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Interest

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Amount of cash inflow (outflow) from financing activities, including discontinued operations. Financing activity cash flows include obtaining resources from owners and providing them with a return on, and a return of, their investment; borrowing money and repaying amounts borrowed, or settling the obligation; and obtaining and paying for other resources obtained from creditors on long-term credit.

+ References

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- Definition

Amount of cash inflow (outflow) from operating activities, including discontinued operations. Operating activity cash flows include transactions, adjustments, and changes in value not defined as investing or financing activities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
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- Definition

Amount of cumulative effect of the change in accounting principle or new accounting pronouncement on retained earnings or other components of equity or net assets in the statement of financial position as of the beginning of the earliest period presented.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Amount of the effect of a change in accounting principle on net income.

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- Definition

Amount of the effect of a change in accounting principle on operating profit or loss.

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Significant Accounting Policies - Narrative (Details) - USD ($)	3 Months Ended		6 Months Ended	9 Months Ended
	Mar. 23, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2016	Sep. 30, 2015	Jan. 01, 2014
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Net Cash Provided by (Used in) Financing Activities				$ 1,251,000,000	$ 5,402,000,000
Net Cash Provided by (Used in) Operating Activities				7,363,000,000	5,674,000,000
Pepco Holdings LLC [Member] \| Predecessor [Member]
Error Corrections and Prior Period Adjustments Restatement [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Effect of Change on Operating Results		$ 1,000,000			1,000,000
Net Cash Provided by (Used in) Financing Activities	$ 372,000,000				491,000,000
Net Cash Provided by (Used in) Operating Activities	$ 264,000,000				601,000,000
Pepco Holdings LLC [Member] \| Successor [Member]
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Net Cash Provided by (Used in) Financing Activities			$ 65,000,000
Net Cash Provided by (Used in) Operating Activities			$ 546,000,000
Delmarva Power and Light Company [Member]
Error Corrections and Prior Period Adjustments Restatement [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Effect of Change on Operating Results		1,000,000
Net Cash Provided by (Used in) Financing Activities				(14,000,000)	53,000,000
Net Cash Provided by (Used in) Operating Activities				267,000,000	188,000,000
Atlantic City Electric Company [Member]
Error Corrections and Prior Period Adjustments Restatement [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Effect of Change on Operating Results					1,000,000
New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets						$ 12,000,000
New Accounting Pronouncement or Change in Accounting Principle, Effect of Change on Net Income		8,000,000			9,000,000
Net Cash Provided by (Used in) Financing Activities				74,000,000	40,000,000
Net Cash Provided by (Used in) Operating Activities				315,000,000	178,000,000
Potomac Electric Power Company [Member]
Error Corrections and Prior Period Adjustments Restatement [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Interest		$ 1,000,000
New Accounting Pronouncement or Change in Accounting Principle, Effect of Change on Operating Results					1,000,000
Net Cash Provided by (Used in) Financing Activities				28,000,000	148,000,000
Net Cash Provided by (Used in) Operating Activities				$ 504,000,000	$ 213,000,000