Financial Risk Management Activities (Schedule Of Derivative Instruments Designated As Cash Flow Hedges) (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended	9 Months Ended	3 Months Ended	9 Months Ended
Sep. 30, 2012 PSEG [Member]	Sep. 30, 2012 PSEG [Member]	Sep. 30, 2011 PSEG [Member]	Sep. 30, 2012 Power [Member]	Sep. 30, 2011 Power [Member]	Sep. 30, 2012 Operating Revenues [Member] PSEG [Member] Energy-Related Contracts [Member]	Sep. 30, 2011 Operating Revenues [Member] PSEG [Member] Energy-Related Contracts [Member]	Sep. 30, 2012 Operating Revenues [Member] PSEG And Power [Member] Energy-Related Contracts [Member]	Sep. 30, 2011 Operating Revenues [Member] PSEG And Power [Member] Energy-Related Contracts [Member]	Sep. 30, 2012 Operating Revenues [Member] Power [Member] Energy-Related Contracts [Member]	Sep. 30, 2011 Operating Revenues [Member] Power [Member] Energy-Related Contracts [Member]	Sep. 30, 2012 Energy Costs [Member] PSEG [Member] Energy-Related Contracts [Member]	Sep. 30, 2011 Energy Costs [Member] PSEG [Member] Energy-Related Contracts [Member]	Sep. 30, 2012 Energy Costs [Member] Power [Member] Energy-Related Contracts [Member]	Sep. 30, 2011 Energy Costs [Member] Power [Member] Energy-Related Contracts [Member]	Sep. 30, 2012 Interest Expense [Member] PSEG [Member] Interest Rate Swap [Member]	Sep. 30, 2011 Interest Expense [Member] PSEG [Member] Interest Rate Swap [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Pre-Tax Gain (Loss) attributed to Cash Flow Hedges Recognized in AOCI on Derivatives (Effective Portion)		$ 23	$ (19)	$ 23	$ 19	$ 27	$ 18	$ (3)	$ 21	$ 27	$ 18	$ (4)	$ 1	$ (4)	$ 1	$ 0	$ 0
Amount of Pre-Tax Gain (Loss) Recognized in Income on Derivatives (Ineffective Portion)	1	(1)		(1)	1	(1)	1	(1)	0	(1)	1	0	0	0	0	0	0
Amount of Pre-Tax Gain (Loss) attributed to Cash Flow Hedges Reclassified from AOCI into Operating Revenues (Effective Portion)						67	152	15	60	67	152
Amount of Pre-Tax Gain (Loss) attributed to Cash Flow Hedges Reclassified from AOCI into Energy Costs (Effective Portion)												(9)	2	(9)	2
Amount of gain (loss) attributed to cash flow hedges reclassified from AOCI into Earnings (effective portion)																(1)	(1)
Amount of Pre-Tax Gain (Loss) attributed to Cash Flow Hedges Reclassified from AOCI into Energy Costs (Effective Portion)		$ 57	$ 153	$ 58	$ 154

The amount of net gains or losses on a cash flow hedge reclassified in the period to cost of sales from accumulated other comprehensive income.

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The amount of net gains or losses on a cash flow hedge reclassified in the period to earnings from accumulated other comprehensive income.

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The amount of net gains or losses on a cash flow hedge reclassified in the period to interest expense from accumulated other comprehensive income.

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The amount of net gains or losses on a cash flow hedge reclassified to revenues from accumulated other comprehensive income.

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The net gain (loss) recognized in earnings during the reporting period representing the amount of the cash flow hedges' ineffectiveness.

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Amount of unrealized gain (loss) related to derivatives designated as cash flow hedging instruments, recorded in results of operations to the extent that the cash flow hedge is determined to be ineffective.

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