Approximate annual commitments under capital leases due after one year five years.

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- Definition

Approximate annual commitments under capital leases due after one year four years.

+ References

No definition available.

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- Definition

Approximate annual commitments under capital leases due after one year.

+ References

No definition available.

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- Definition

Approximate annual commitments under capital leases due after one year three years.

+ References

No definition available.

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- Definition

Approximate annual commitments under capital leases due after one year two years.

+ References

No definition available.

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- Definition

Approximate annual commitments under capital leases due thereafter.

+ References

No definition available.

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- Definition

Impairment loss after tax.

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No definition available.

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- Definition

Long lived assets after impairment carrying value.

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No definition available.

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- Definition

Long lived assets before impairment carrying value.

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No definition available.

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- Definition

Maximum estimated costs for closure of the operations.

+ References

No definition available.

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- Definition

Minimum estimated costs for closure of the operations.

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- Definition

Percentage of change in estimated cash flow does not impact on estimated fair value of assets.

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No definition available.

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- Definition

Percentage of increase decrease in discount rate assumptions.

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No definition available.

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Range of discount rates.

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No definition available.

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- Definition

Term length.

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No definition available.

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- Definition

Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

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-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 45

-Paragraph 4

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- Definition

The carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 410

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (c)

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Asset Retirement Obligation

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- Definition

Amount of minimum lease payments for capital leases net of executory costs, which include amounts paid by the lessee to the lessor for insurance, maintenance and taxes.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 30

-Section 50

-Paragraph 1

-Subparagraph (b)

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- Definition

Present value of minimum lease payments for capital leases net of executory costs, including amounts paid by the lessee to the lessor for insurance, maintenance and taxes.

+ References

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- Definition

The estimate of the lease property's economic value at the end of the direct financing lease term excluding any amounts guaranteed by either the lessee or a third-party.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 30

-Section 50

-Paragraph 4

-Subparagraph (a)(2)

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A general description of the nature of the existing leasing arrangements of a lessor for all types of capital leases (sales-type, direct financing, leveraged) including, but not limited to: (1) unguaranteed residual values, if any, (2) restrictions imposed by lease arrangements; (3) unusual provisions or conditions; (4) contingent rentals, if any; and (5) lease expiration dates.

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-Section 50

-Paragraph 4

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-Topic 840

-SubTopic 30

-Section 50

-Paragraph 5

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- Definition

The total period end amount of plant in service and construction in progress net of accumulated depreciation for the utility's share of jointly owned electricity generation plant.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 980

-SubTopic 360

-Section S99

-Paragraph 1

-Subparagraph (SAB TOPIC 10.C)

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-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 10

-Section C

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Property, Plant and Equipment - Additional Information (Detail) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Property, Plant and Equipment [Line Items]
Present value of future minimum lease payments	$ 152,000,000
Semi-annual payments	8,000,000
Description of lease term	Over a 25-year period that began in December 1994
Guaranteed residual value due at end of lease term	1
Approximate annual commitments, 2015	15,000,000
Approximate annual commitments, 2016	15,000,000
Approximate annual commitments, 2017	15,000,000
Approximate annual commitments, 2018	15,000,000
Approximate annual commitments, 2019	16,000,000
Impairment losses	81,000,000us-gaap_AssetImpairmentCharges	4,000,000us-gaap_AssetImpairmentCharges	12,000,000us-gaap_AssetImpairmentCharges
Long-lived assets before impairment, carrying amount	83,000,000
Long lived assets after impairment, carrying amount	2,000,000
Percentage of change in the estimated cash flows	10.00%
Percentage of change in discount rate assumptions	1.00%
Asset retirement obligation		2,000,000us-gaap_AssetRetirementObligation
Minimum [Member]
Property, Plant and Equipment [Line Items]
Range of discount rates	10.00%
Maximum [Member]
Property, Plant and Equipment [Line Items]
Range of discount rates	16.00%
Pepco Energy Services [Member]
Property, Plant and Equipment [Line Items]
Impairment losses	81,000,000	4,000,000	12,000,000
Impairment losses, after-tax	48,000,000	3,000,000	7,000,000
Buzzard Point and Benning Road [Member]
Property, Plant and Equipment [Line Items]
Asset retirement obligation	0	2,000,000
Subsidiaries [Member]
Property, Plant and Equipment [Line Items]
Jointly owned plant, net book value ownership	15,000,000	12,000,000
Impairment losses		4,000,000
Impairment losses, after-tax		3,000,000
Conectiv Energy [Member]
Property, Plant and Equipment [Line Items]
Asset retirement obligation	6,000,000
Minimum estimated costs for closure of the operations	2,000,000
Maximum estimated costs for closure of the operations	3,000,000
Annual post-closure operations, maintenance and monitoring period	30 years
Potomac Electric Power Co [Member]
Property, Plant and Equipment [Line Items]
Semi-annual payments	8,000,000
Description of lease term	Over a 25-year period that began in December 1994
Guaranteed residual value due at end of lease term	1
Approximate annual commitments, 2015	15,000,000
Approximate annual commitments, 2016	15,000,000
Approximate annual commitments, 2017	15,000,000
Approximate annual commitments, 2018	15,000,000
Approximate annual commitments, thereafter	16,000,000
Atlantic City Electric Co [Member]
Property, Plant and Equipment [Line Items]
Jointly owned plant, net book value ownership	$ 11,000,000	$ 8,000,000