Financial Risk Management Activities (Narrative) (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013	Dec. 31, 2013
Derivatives, Fair Value [Line Items]
Net cash collateral received in connection with net derivative contracts	$ 155		$ 155		$ 2
Aggregate amount of accumulated other comprehensive income (loss) attributed to interest rate derivatives designated as cash flow hedges			(1)
Aggregate fair value of derivative contracts in a liability position that contains triggers for additional collateral	116		116		91
Additional collateral aggregate fair value	760		760		691
Power [Member]
Derivatives, Fair Value [Line Items]
Amount of after-tax gains on derivatives designated and effective as cash flow hedges expected to be reclassified to earnings during the 12 months following period end	2		2
Credit exposure, percentage			92.00%
Number of active counterparties on credit risk derivatives	153		153
Power [Member] | Senior Notes 5.32% Due September 2016 [Member]
Derivatives, Fair Value [Line Items]
Senior Notes converted into variable rate debt	300		300
PSEG [Member]
Derivatives, Fair Value [Line Items]
Number of interest rate swaps outstanding, total	7		7
Aggregate amount of series of interest rate swaps converting to variable-rate debt	850		850
Senior Notes converted into variable rate debt	303		303
Fair value of interest rate swaps designated as underlying hedges	32		32		38
Aggregate fair value of derivative contracts in a liability position that contains triggers for additional collateral	37		37		39
Additional collateral aggregate fair value	79		79		52
Amount of reduction in interest expense attributed to interest rate swaps designated as fair value hedges	5	5	10	10
PSEG [Member] | Senior Notes 5.5% Due December 2015 [Member]
Derivatives, Fair Value [Line Items]
Senior Notes converted into variable rate debt	300		300
Stated interest rate of debt instrument	5.50%		5.50%
PSEG [Member] | Senior Notes 5.32% Due September 2016 [Member]
Derivatives, Fair Value [Line Items]
Stated interest rate of debt instrument	5.32%		5.32%
PSEG [Member] | Senior Notes 2.75% Due September 2016 [Member]
Derivatives, Fair Value [Line Items]
Senior Notes converted into variable rate debt	250		250
Stated interest rate of debt instrument	2.75%		2.75%
Non Current Assets [Member]
Derivatives, Fair Value [Line Items]
Net cash collateral received in connection with net derivative contracts	$ (4)		$ (4)		$ (3)