Fair Value Measurements (Schedule Of Quantitative Information About Level 3 Fair Value Measurements) (Detail) (USD $) In Millions, unless otherwise specified	9 Months Ended		12 Months Ended
	Sep. 30, 2014		Dec. 31, 2013
Power [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value	$ 0		$ 4
Liabilities, Fair Value	(21)		(10)
PSE And G [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value	13		94
Liabilities, Fair Value	0		0
PSEG [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value	13		98
Liabilities, Fair Value	(21)		(10)
Electric Swaps [Member] | Power [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value			3
Liabilities, Fair Value			(1)
Valuation Technique (s)			Discounted Cash Flow
Significant Unobservable Inputs			Power Basis
Electric Load Contracts [Member] | Power [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value	0		0
Liabilities, Fair Value	(21)		(8)
Valuation Technique (s)	Discounted Cash Flow		Discounted Cash Flow
Significant Unobservable Inputs	Historic Load Variability		Historic Load Variability
Various [Member] | Power [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value	0	[1]	1	[2]
Liabilities, Fair Value	0	[1]	(1)	[2]
Forward Contracts [Member] | PSE And G [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value	13		94
Liabilities, Fair Value	$ 0		$ 0
Valuation Technique (s)	Discounted Cash Flow		Discounted Cash Flow
Significant Unobservable Inputs	Transportation Costs		Transportation Costs
Minimum [Member] | Electric Load Contracts [Member] | Power [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Historic Load Variability	0.00%		(5.00%)
Minimum [Member] | MWh [Member] | Electric Swaps [Member] | Power [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Power Basis Range			0
Minimum [Member] | MWh [Member] | Forward Contracts [Member] | PSE And G [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Transportation Costs	0.70		0.70
Maximum [Member] | Electric Load Contracts [Member] | Power [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Historic Load Variability	10.00%		10.00%
Maximum [Member] | MWh [Member] | Electric Swaps [Member] | Power [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Power Basis Range			10
Maximum [Member] | MWh [Member] | Forward Contracts [Member] | PSE And G [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Transportation Costs	1		1

[1] Includes gas supply positions and long-term electric capacity positions which were immaterial as of September 30, 2014.

[2] Includes gas supply positions which were immaterial as of December 31, 2013.