Fair Value Measurements (Changes In Level 3 Assets And (Liabilities) Measured At Fair Value On A Recurring Basis) (Detail) - USD ($) $ in Millions		3 Months Ended				6 Months Ended
		Jun. 30, 2015		Jun. 30, 2014		Jun. 30, 2015		Jun. 30, 2014
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Settlements		$ (4)		$ (1)		$ (16)		$ 58
Power [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Gains and losses attributable to changes in net derivative assets and liabilities, included in Operating Income		5		6		8		(58)
Gains and losses attributable to changes in net derivative assets and liabilities, unrealized		0		6		(9)		1
Net Derivative Assets (Liabilities) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Opening Balance		9		1		37		88
Included in Income		5	[1]	6	[1]	8	[1]	(58)	[2]
Included in Regulatory Assets/Liabilities	[3]	(2)		10		(21)		(72)
Purchases, (Sales)		0		0		0		0
Issuances (Settlements)	[4]	(4)		(1)		(16)		58
Transfers In (Out)		0	[5]	(3)	[5]	0		(3)	[5]
Closing Balance		8		13		8		13
Net Derivative Assets (Liabilities) [Member] | Power [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Opening Balance		2		(11)		11		(6)
Included in Income		5	[1]	6	[1]	8	[1]	(58)	[2]
Included in Regulatory Assets/Liabilities	[3]	0		0		0		0
Purchases, (Sales)		0		0		0		0
Issuances (Settlements)	[4]	(4)		(1)		(16)		58
Transfers In (Out)		0	[5]	(3)	[5]	0		(3)	[5]
Closing Balance		3		(9)		3		(9)
Net Derivative Assets (Liabilities) [Member] | PSE And G [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Opening Balance		7		12		26		94
Included in Income		0	[1]	0	[1]	0	[1]	0	[2]
Included in Regulatory Assets/Liabilities	[3]	(2)		10		(21)		(72)
Purchases, (Sales)		0		0		0		0
Issuances (Settlements)	[4]	0		0		0		0
Transfers In (Out)		0	[5]	0	[5]	0		0	[5]
Closing Balance		$ 5		$ 22		$ 5		$ 22

[1] PSEG’s and Power’s gains and losses attributable to changes in net derivative assets and liabilities includes $5 million and $8 million in Operating Income for the three months and six months ended June 30, 2015, respectively. The $5 million in Operating Income is realized. Of the $8 million in Operating Income, $(9) million is unrealized.

[2] PSEG’s and Power’s gains and losses attributable to changes in net derivative assets and liabilities include $6 million and $(58) million in Operating Income for the three months and six months ended June 30, 2014, respectively. The $6 million in Operating Income is unrealized. Of the $(58) million in Operating Income, $1 million is unrealized.

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

[4] Represents $(4) million and $(16) million in settlements for the three months and six months ended June 30, 2015. Includes $(1) million and $58 million in settlements for the three months and six months ended June 30, 2014.

[5] During the three months and six months ended June 30, 2014, $(3) million of net derivative assets/liabilities were transferred from Level 3 to Level 2 due to more observable pricing for the underlying securities. The transfers were recognized as of the beginning of the quarters in which the transfers first occurred as per PSEG's policy.