Financial Risk Management Activities (Schedule Providing Credit Risk From Others, Net Of Collateral) (Details) (USD $) In Millions	Sep. 30, 2011
Power [Member] | Investment Grade- External Rating [Member]
Derivative [Line Items]
Current Exposure	$ 396
Securities held as Collateral	46
Net Exposure	392
Number of Counterparties greater than 10%	3
Net Exposure of Counterparties greater than 10%	242	[1]
Power [Member] | Non-Investment Grade- External Rating [Member]
Derivative [Line Items]
Current Exposure	11
Securities held as Collateral	0
Net Exposure	11
Number of Counterparties greater than 10%	0
Net Exposure of Counterparties greater than 10%	0
Power [Member] | Investment Grade- No External Rating [Member]
Derivative [Line Items]
Current Exposure	9
Securities held as Collateral	0
Net Exposure	9
Number of Counterparties greater than 10%	0
Net Exposure of Counterparties greater than 10%	0
Power [Member] | Non-Investment Grade- No External Rating [Member]
Derivative [Line Items]
Current Exposure	9
Securities held as Collateral	0
Net Exposure	9
Number of Counterparties greater than 10%	0
Net Exposure of Counterparties greater than 10%	0
Power [Member]
Derivative [Line Items]
Current Exposure	425
Securities held as Collateral	46
Net Exposure	421
Number of Counterparties greater than 10%	3
Net Exposure of Counterparties greater than 10%	242
PSE&G [Member]
Derivative [Line Items]
Net Exposure	129
Nonaffiliated [Member]
Derivative [Line Items]
Net Exposure	$ 113

[1] Includes net exposure of $129 million with PSE&G. The remaining net exposure of $113 million is with two nonaffiliated power purchasers which are regulated investment grade counterparties.