Fair Value Measurements (A Reconciliation Of The Beginning And Ending Balances Of Level 3 Derivative Contracts And Securities) (Details) (USD $) In Millions	3 Months Ended				9 Months Ended
	Sep. 30, 2011		Sep. 30, 2010		Sep. 30, 2011		Sep. 30, 2010
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Closing Balance	$ 0				$ 0
Gains and losses attributable to changes in net derivative assets and liabilities, included in Operating Income					(28)		8
Gains and losses attributable to changes in net derivative assets and liabilities included in OCI	1				(2)		28
Gains and losses attributable to changes in net derivative assets and liabilities included in Income from Discontinued Operations	1				3		25
Gains and losses attributable to changes in net derivative assets and liabilities, unrealized	31		32		(25)		9
Gains and losses attributable to changes in net derivative assets and liabilities, realized					(3)		(1)
Purchases	10				65
Sales	(36)
Issuances	(5)				(25)
Settlements	8				3
PSEG (Parent) [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Gains and losses attributable to changes in net derivative assets and liabilities, included in Operating Income	12
Power [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Gains and losses attributable to changes in net derivative assets and liabilities, included in Operating Income			17
Gains and losses attributable to changes in net derivative assets and liabilities included in OCI			14
Gains and losses attributable to changes in net derivative assets and liabilities included in Income from Discontinued Operations			2
Gains and losses attributable to changes in net derivative assets and liabilities, realized	(19)		(15)
Net Derivative Assets [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Opening Balance	(3)		168		47		105
Included in Income	13	[1]	33	[1]	(27)	[2]	61	[2]
Included in Regulatory Assets/Liabilities	(27)	[3]	(11)	[3]	(31)	[3]	34	[3]
Purchases, (Sales)	10	[4]			29	[4]
(Issuances) (Settlements)	3	[5]			(22)	[5]
Purchases, (Sales) and Settlements			(2)				(12)
Transfers In (Out)	0				0
Closing Balance	(4)		188		(4)		188
NDT Funds [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Opening Balance			6		8		9
Included in Income			0	[1]	0	[2]	0	[2]
Included in Regulatory Assets/Liabilities			0	[3]	0	[3]	0	[3]
Purchases, (Sales)					0	[4]
(Issuances) (Settlements)					0	[5]
Purchases, (Sales) and Settlements			3				0
Transfers In (Out)					(8)
Closing Balance	0		9		0		9
Rabbi Trust Funds [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Opening Balance			16				14
Included in Income			0	[1]			0	[2]
Included in Regulatory Assets/Liabilities			0	[3]			0	[3]
Purchases, (Sales) and Settlements			(16)				(14)
Closing Balance			$ 0				$ 0

[1] PSEG's and Power's gains and losses are mainly attributable to changes in net derivative assets and liabilities of which $12 million and $17 million are included in Operating Income, $1 million and $14 million are included in OCI, and less than $1 million and $2 million are included in Income from Discontinued Operations in 2011 and 2010, respectively. Of the $12 million in Operating Income in 2011, $31 million is unrealized and $(19) million is realized. Of the $17 million in Operating Income in 2010, $32 million is unrealized and $(15) million is realized.

[2] PSEG's and Power's gains and losses are mainly attributable to changes in net derivative assets and liabilities of which $(28) million and $8 million are included in Operating Income, $(2) million and $28 million are included in OCI, and $3 million and $25 million are included in Income from Discontinued Operations in 2011 and 2010, respectively. Of the $(28) million in Operating Income in 2011, $(25) million is unrealized and $(3) million is realized. Of the $8 million in Operating Income in 2010, $9 million is unrealized and $(1) million is realized.

[3] Mainly includes gains/losses on PSE&G's derivative contracts that are not included in either earnings or OCI, as they are deferred as a Regulatory Asset/Liability and are expected to be recovered from/returned to PSE&G's customers.

[4] Represents $10 million in purchases for the three months ended September 30, 2011. Includes $65 million in purchases and $(36) million in sales for the nine months ended September 30, 2011.

[5] Includes $(5) million in issuances and $8 million in settlements for the three months ended September 30, 2011. Includes $(25) million in issuances and $3 million in settlements for the nine months ended September 30, 2011.