Credit Risk Derivative Liabilities At Fair Value Net

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- Definition

Debt Instrument Unused Borrowing Capacity Amount For Subsidiary

+ Details

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- Definition

Net settlement amount in the event of a downgrade below investment grade

+ Details

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- Definition

The aggregate fair value of assets that are already posted, at the end of the reporting period, as collateral for derivative instruments with credit-risk-related contingent features.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4H

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=6935481&loc=SL5624258-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 44D

-Subparagraph c

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

Fair value as of the balance sheet date of credit risk derivative liabilities, which includes all such derivative instruments in hedging and non-hedging relationships that are recognized as liabilities on the balance sheet.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 17

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

-Section 50

-Paragraph 10

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6947722&loc=d3e13433-108611

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- Definition

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

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Subparagraph b

-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(b))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Net Increase or Decrease in the fair value of the derivative or group of derivatives included in earnings.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4A

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6935481&loc=SL5618551-113959

+ Details

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- Definition

Decrease in the fair value of the derivative or group of derivatives included in earnings in the period.

+ References

+ Details

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Derivative Instruments And Hedging Activities (Narrative) (Details) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010	Dec. 31, 2010
Credit risk derivative liabilities, at fair value	$ 74,000,000		$ 74,000,000		$ 156,000,000
Derivative Gain Loss On Derivative, Net	(4,000,000)	1,000,000	(11,000,000)	2,000,000
Net settlement amount in the event of a downgrade below investment grade	129,000,000		129,000,000		182,000,000
Cash collateral posted	5,000,000		5,000,000
Credit risk derivative liabilities, at fair value net	69,000,000		69,000,000
Pepco Energy Services [Member]
Cash plus borrowing capacity to meet future liquidity needs	1,400,000,000		1,400,000,000		1,200,000,000
Debt instrument unused borrowing capacity amount for subsidiary	547,000,000		547,000,000		728,000,000
PHI [Member]
Derivative Gain Loss On Derivative, Net		9,000,000
Derivative, Loss on Derivative		15,000,000
Natural Gas Derivatives [Member]
Derivative Gain Loss On Derivative, Net			$ 31,000,000