Financial Risk Management Activities (Narrative) (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013	Dec. 31, 2013
Derivatives, Fair Value [Line Items]
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	91		91
Additional collateral aggregate fair value	802		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	1
Credit exposure, percentage	97.00%
Number of active counterparties on credit risk derivatives	158
Power [Member] | Senior Notes 5.32% Due September 2016 [Member]
Derivatives, Fair Value [Line Items]
Senior Notes converted into variable rate debt	300
PSEG [Member]
Derivatives, Fair Value [Line Items]
Number of interest rate swaps outstanding, total	7
Aggregate amount of series of interest rate swaps converting to variable-rate debt	850
Senior Notes converted into variable rate debt	303
Fair value of interest rate swaps designated as underlying hedges	34		38
Aggregate fair value of derivative contracts in a liability position that contains triggers for additional collateral	39		39
Additional collateral aggregate fair value	52		52
Amount of reduction in interest expense attributed to interest rate swaps designated as fair value hedges	5	5
PSEG [Member] | Senior Notes 5.5% Due December 2015 [Member]
Derivatives, Fair Value [Line Items]
Senior Notes converted into variable rate debt	300
Stated interest rate of debt instrument	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%
PSEG [Member] | Senior Notes 2.75% Due September 2016 [Member]
Derivatives, Fair Value [Line Items]
Senior Notes converted into variable rate debt	$ 250
Stated interest rate of debt instrument	2.75%