Change Of Control Description

No definition available.

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- Definition

Combined maximum amount of credit facility available to parent in the event of the adjustment of the credit sub-limits at the borrowers election.

+ References

No definition available.

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- Definition

Commercial paper program maximum.

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No definition available.

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Commercial paper weighted average maturity.

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- Definition

Contractual Obligation Payments Period

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No definition available.

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- Definition

Debt instrument variable interest rate in addition to one month LIBOR's effective rate.

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No definition available.

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- Definition

Maximum Number Of Sublimit Reallocation Per Year

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- Definition

Ownership Percentage Basis Point For Change In Control

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- Definition

Parent Company Borrowing Capacity Under Credit Facilities

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- Definition

The maximum amount of the credit facility that the parent company may obtain for letters of credit.

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No definition available.

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- Definition

Purchase Price Under Agreement To Sell

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- Definition

Maximum ratio of deferrable interest subordinated debt to capitalization permitted to be excluded from the computation of total indebtedness under the credit facility and term loan agreements.

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No definition available.

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- Definition

Maximum ratio of indebtedness to capitalization permitted under the credit facility and term loan agreements.

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No definition available.

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- Definition

Maximum percentage of credit facility that each company may borrow under the swing-line loan sub-facility.

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No definition available.

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- Definition

Subsidiary borrowing limit under parents credit facility in the event of the adjustment of the credit sub-limits at the borrowers election.

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No definition available.

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- Definition

Swing Line Loan Repayment Period

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No definition available.

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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No definition available.

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- Definition

Face (par) amount of debt instrument at time of issuance.

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Contractual interest rate for funds borrowed, under the debt agreement.

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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.

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No definition available.

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Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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Amount of the required periodic payments applied to principal.

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Amount of unused borrowing capacity under the long-term financing arrangement that is available to the entity as of the balance sheet date.

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Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

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Date the credit facility terminates, in CCYY-MM-DD format.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

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The cash outflow to repay long-term debt that is not secured by collateral. Excludes repayments of tax exempt unsecured debt.

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Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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Weighted average interest rate of short-term debt outstanding.

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Debt - Additional Information (Detail)			1 Months Ended			6 Months Ended		12 Months Ended
Debt - Additional Information (Detail)	Jul. 31, 2015 USD ($)	Oct. 24, 2013 USD ($)	Jul. 31, 2015 USD ($)	Jun. 30, 2015 USD ($)	Apr. 30, 2015 USD ($)	Jun. 30, 2015 USD ($) Sublimit	Jun. 30, 2014 USD ($)	Dec. 31, 2014 USD ($)	May. 31, 2015 USD ($)
Debt Instrument [Line Items]
Amended description of Change in Control						The Consent amends the definition of "Change in Control" in the credit agreement to mean, following consummation of the Merger, an event or series of events by which Exelon no longer owns, directly or indirectly, 100% of the outstanding shares of voting stock of Pepco Holdings.
Ownership percentage of outstanding voting stock for Change in Control				100.00%		100.00%
On-going commercial paper				$ 875,000,000		$ 875,000,000
Short-term debt				$ 798,000,000		$ 798,000,000		$ 729,000,000
Commercial paper weighted average maturity, in days						9 days
Reacquisitions of long-term debt						$ 133,000,000	$ 206,000,000
Purchase price								$ 12,000,000
Contract payment period								9 years
Pepco Energy Services [Member]
Debt Instrument [Line Items]
Reacquisitions of long-term debt					$ 5,000,000
Purchase price		$ 7,000,000
Contract payment period		23 years
Commercial Paper [Member]
Debt Instrument [Line Items]
Commercial paper weighted average interest rate				0.74%		0.74%
Unsecured Syndicated Credit Facility [Member]
Debt Instrument [Line Items]
Credit facility, termination date						Aug. 01, 2018
Line of credit facility maximum borrowing capacity				$ 1,500,000,000		$ 1,500,000,000
Parent company credit facility letter of credit, maximum						$ 500,000,000
Same day borrowings maximum percentage amount						10.00%
Swingline loan repayment period						14 days
Credit facility borrowing capacity				750,000,000		$ 750,000,000
Maximum amount of credit available to parent						1,250,000,000
Subsidiary borrowing limit under parent's credit facility						$ 500,000,000
Maximum number of sublimit reallocations per year \| Sublimit						8
Borrowing capacity under the credit facility				826,000,000		$ 826,000,000		$ 875,000,000
Utility subsidiaries combined cash and borrowing capacity				$ 521,000,000		$ 521,000,000		413,000,000
Unsecured Syndicated Credit Facility [Member] \| Federal Funds Effective Rate [Member]
Debt Instrument [Line Items]
Debt instrument, percentage added to reference rate						0.50%
Unsecured Syndicated Credit Facility [Member] \| LIBOR [Member]
Debt Instrument [Line Items]
Debt instrument, percentage added to reference rate						1.00%
Unsecured Syndicated Credit Facility [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Ratio of indebtedness to total capitalization						65.00%
Ratio of deferrable interest subordinated debt to total capitalization				15.00%		15.00%
Series 2002-1 Bonds, Class A-3 [Member] \| Subsequent Event [Member]
Debt Instrument [Line Items]
Debt instrument periodical principal payments			$ 1,000,000
Series 2003-1 Bonds, Class A-3 [Member] \| Subsequent Event [Member]
Debt Instrument [Line Items]
Debt instrument periodical principal payments			3,000,000
Series 2002-1 Bonds, Class A-4 [Member] \| Subsequent Event [Member]
Debt Instrument [Line Items]
Debt instrument periodical principal payments			$ 6,000,000
Potomac Electric Power Co [Member]
Debt Instrument [Line Items]
Amended description of Change in Control						The Consent amends the definition of "Change in Control" in the credit agreement to mean, following consummation of the Merger, an event or series of events by which Exelon no longer owns, directly or indirectly, 100% of the outstanding shares of voting stock of Pepco Holdings.
Ownership percentage of outstanding voting stock for Change in Control				100.00%		100.00%
On-going commercial paper				$ 500,000,000		$ 500,000,000
Short-term debt								104,000,000
Commercial paper weighted average maturity, in days						5 days
Reacquisitions of long-term debt						$ 12,000,000	175,000,000
Purchase price								$ 12,000,000
Contract payment period								9 years
Potomac Electric Power Co [Member] \| Commercial Paper [Member]
Debt Instrument [Line Items]
Short-term debt				$ 0		$ 0
Commercial paper weighted average interest rate				0.43%		0.43%
Potomac Electric Power Co [Member] \| Unsecured Syndicated Credit Facility [Member]
Debt Instrument [Line Items]
Credit facility, termination date						Aug. 01, 2018
Line of credit facility maximum borrowing capacity				$ 1,500,000,000		$ 1,500,000,000
Parent company credit facility letter of credit, maximum						$ 500,000,000
Same day borrowings maximum percentage amount						10.00%
Swingline loan repayment period						14 days
Credit facility borrowing capacity				200,000,000		$ 200,000,000
Maximum amount of credit available to parent						1,250,000,000
Subsidiary borrowing limit under parent's credit facility						$ 500,000,000
Maximum number of sublimit reallocations per year \| Sublimit						8
Utility subsidiaries combined cash and borrowing capacity				$ 521,000,000		$ 521,000,000		$ 413,000,000
Potomac Electric Power Co [Member] \| Unsecured Syndicated Credit Facility [Member] \| Federal Funds Effective Rate [Member]
Debt Instrument [Line Items]
Debt instrument, percentage added to reference rate						0.50%
Potomac Electric Power Co [Member] \| Unsecured Syndicated Credit Facility [Member] \| LIBOR [Member]
Debt Instrument [Line Items]
Debt instrument, percentage added to reference rate						1.00%
Potomac Electric Power Co [Member] \| Unsecured Syndicated Credit Facility [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Ratio of indebtedness to total capitalization						65.00%
Ratio of deferrable interest subordinated debt to total capitalization				15.00%		15.00%
Delmarva Power & Light Co/De [Member]
Debt Instrument [Line Items]
Amended description of Change in Control						The Consent amends the definition of "Change in Control" in the credit agreement to mean, following consummation of the Merger, an event or series of events by which Exelon no longer owns, directly or indirectly, 100% of the outstanding shares of voting stock of Pepco Holdings.
Ownership percentage of outstanding voting stock for Change in Control				100.00%		100.00%
On-going commercial paper				$ 500,000,000		$ 500,000,000
Short-term debt				135,000,000		$ 135,000,000		211,000,000
Commercial paper weighted average maturity, in days						5 days
Reacquisitions of long-term debt						$ 100,000,000
Delmarva Power & Light Co/De [Member] \| Commercial Paper [Member]
Debt Instrument [Line Items]
Short-term debt				$ 30,000,000		$ 30,000,000
Commercial paper weighted average interest rate				0.46%		0.46%
Delmarva Power & Light Co/De [Member] \| Unsecured Syndicated Credit Facility [Member]
Debt Instrument [Line Items]
Credit facility, termination date						Aug. 01, 2018
Line of credit facility maximum borrowing capacity				$ 1,500,000,000		$ 1,500,000,000
Parent company credit facility letter of credit, maximum						$ 500,000,000
Same day borrowings maximum percentage amount						10.00%
Swingline loan repayment period						14 days
Credit facility borrowing capacity				250,000,000		$ 250,000,000
Maximum amount of credit available to parent						1,250,000,000
Subsidiary borrowing limit under parent's credit facility						$ 500,000,000
Maximum number of sublimit reallocations per year \| Sublimit						8
Utility subsidiaries combined cash and borrowing capacity				$ 521,000,000		$ 521,000,000		413,000,000
Debt instrument variable interest rate in addition to one month London Interbank Offered Rate				1.00%		1.00%
Delmarva Power & Light Co/De [Member] \| Unsecured Syndicated Credit Facility [Member] \| Federal Funds Effective Rate [Member]
Debt Instrument [Line Items]
Debt instrument, percentage added to reference rate						0.50%
Delmarva Power & Light Co/De [Member] \| Unsecured Syndicated Credit Facility [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Ratio of indebtedness to total capitalization						65.00%
Ratio of deferrable interest subordinated debt to total capitalization				15.00%		15.00%
Delmarva Power & Light Co/De [Member] \| 4.15% Due 2045 [Member] \| First Mortgage Bonds [Member]
Debt Instrument [Line Items]
Debt instrument, face amount									$ 200,000,000
Debt instruments maturity date						May 15, 2045
Debt instrument, interest percentage									4.15%
Delmarva Power & Light Co/De [Member] \| 5.00% Due 2015 [Member]
Debt Instrument [Line Items]
Repayment of unsecured notes				$ 100,000,000
Delmarva Power & Light Co/De [Member] \| 5.00% Due 2015 [Member] \| Unsecured Notes [Member]
Debt Instrument [Line Items]
Debt instrument, interest percentage				5.00%		5.00%
Atlantic City Electric Co [Member]
Debt Instrument [Line Items]
Amended description of Change in Control						The Consent amends the definition of "Change in Control" in the credit agreement to mean, following consummation of the Merger, an event or series of events by which Exelon no longer owns, directly or indirectly, 100% of the outstanding shares of voting stock of Pepco Holdings.
Ownership percentage of outstanding voting stock for Change in Control				100.00%		100.00%
On-going commercial paper				$ 350,000,000		$ 350,000,000
Short-term debt				218,000,000		$ 218,000,000		127,000,000
Commercial paper weighted average maturity, in days						5 days
Reacquisitions of long-term debt						$ 21,000,000	$ 20,000,000
Atlantic City Electric Co [Member] \| Commercial Paper [Member]
Debt Instrument [Line Items]
Short-term debt				$ 218,000,000		$ 218,000,000
Commercial paper weighted average interest rate				0.46%		0.46%
Atlantic City Electric Co [Member] \| Unsecured Syndicated Credit Facility [Member]
Debt Instrument [Line Items]
Credit facility, termination date						Aug. 01, 2018
Line of credit facility maximum borrowing capacity				$ 1,500,000,000		$ 1,500,000,000
Parent company credit facility letter of credit, maximum						$ 500,000,000
Same day borrowings maximum percentage amount						10.00%
Swingline loan repayment period						14 days
Credit facility borrowing capacity				300,000,000		$ 300,000,000
Maximum amount of credit available to parent						1,250,000,000
Subsidiary borrowing limit under parent's credit facility						$ 500,000,000
Maximum number of sublimit reallocations per year \| Sublimit						8
Utility subsidiaries combined cash and borrowing capacity				$ 521,000,000		$ 521,000,000		$ 413,000,000
Debt instrument variable interest rate in addition to one month London Interbank Offered Rate				1.00%		1.00%
Atlantic City Electric Co [Member] \| Unsecured Syndicated Credit Facility [Member] \| Federal Funds Effective Rate [Member]
Debt Instrument [Line Items]
Debt instrument, percentage added to reference rate						0.50%
Atlantic City Electric Co [Member] \| Unsecured Syndicated Credit Facility [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Ratio of indebtedness to total capitalization						65.00%
Ratio of deferrable interest subordinated debt to total capitalization				15.00%		15.00%
Atlantic City Electric Co [Member] \| Series 2002-1 Bonds, Class A-3 [Member]
Debt Instrument [Line Items]
Debt instrument periodical principal payments					7,000,000
Atlantic City Electric Co [Member] \| Series 2002-1 Bonds, Class A-3 [Member] \| Subsequent Event [Member]
Debt Instrument [Line Items]
Debt instrument periodical principal payments	$ 1,000,000
Atlantic City Electric Co [Member] \| Series 2003-1 Bonds, Class A-3 [Member]
Debt Instrument [Line Items]
Debt instrument periodical principal payments					$ 3,000,000
Atlantic City Electric Co [Member] \| Series 2003-1 Bonds, Class A-3 [Member] \| Subsequent Event [Member]
Debt Instrument [Line Items]
Debt instrument periodical principal payments	3,000,000
Atlantic City Electric Co [Member] \| Series 2002-1 Bonds, Class A-4 [Member] \| Subsequent Event [Member]
Debt Instrument [Line Items]
Debt instrument periodical principal payments	$ 6,000,000
PHI [Member] \| Commercial Paper [Member]
Debt Instrument [Line Items]
Short-term debt				$ 445,000,000		$ 445,000,000