Financial Risk Management Activities (Schedule Providing Credit Risk From Others, Net Of Collateral) (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2011
Power [Member]
Derivative [Line Items]
Current Exposure	$ 739
Securities held as Collateral	83
Net Exposure	736
Number of Counterparties greater than 10%	2
Net Exposure of Counterparties greater than 10%	427
PSE&G [Member]
Derivative [Line Items]
Net Exposure	339
Nonaffiliated [Member]
Derivative [Line Items]
Net Exposure	88
Investment Grade- External Rating [Member] | Power [Member]
Derivative [Line Items]
Current Exposure	702
Securities held as Collateral	83
Net Exposure	699
Number of Counterparties greater than 10%	2
Net Exposure of Counterparties greater than 10%	427	[1]
Non-Investment Grade- External Rating [Member] | Power [Member]
Derivative [Line Items]
Current Exposure	27
Securities held as Collateral	0
Net Exposure	27
Number of Counterparties greater than 10%	0
Net Exposure of Counterparties greater than 10%	0
Investment Grade- No External Rating [Member] | Power [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
Non-Investment Grade- No External Rating [Member] | Power [Member]
Derivative [Line Items]
Current Exposure	1
Securities held as Collateral	0
Net Exposure	1
Number of Counterparties greater than 10%	0
Net Exposure of Counterparties greater than 10%	$ 0

[1] Includes net exposure of $339 million with PSE&G. The remaining net exposure of $88 million is with one non-affiliated power purchaser which is a regulated investment grade counterparty.