Fair Value Measurements (Fair Value Of Debt) (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2012		Dec. 31, 2011
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-Term Debt, Carrying Amount	$ 7,978		$ 8,094
Long-Term Debt, Fair Value	9,123		9,283
PSEG [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-Term Debt, Carrying Amount	38	[1]	39	[1]
Long-Term Debt, Fair Value	60	[1]	62	[1]
Power - Recourse Debt [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-Term Debt, Carrying Amount	2,685	[2]	2,751	[2]
Long-Term Debt, Fair Value	3,092	[2]	3,158	[2]
PSE And G [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-Term Debt, Carrying Amount	4,271	[2]	4,270	[2]
Long-Term Debt, Fair Value	4,875	[2]	4,905	[2]
Transition Funding (PSE&G) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-Term Debt, Carrying Amount	845	[2]	895	[2]
Long-Term Debt, Fair Value	954	[2]	1,016	[2]
Transition Funding II [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-Term Debt, Carrying Amount	44	[2]	44	[2]
Long-Term Debt, Fair Value	47	[2]	47	[2]
Energy Holdings Project Level, Non-Recourse Debt [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-Term Debt, Carrying Amount	95	[3]	95	[3]
Long-Term Debt, Fair Value	95	[3]	95	[3]
DH [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Non-Recourse Debt	50
Fair value of non-recourse debt	$ 45

[1] Fair value represents net offsets to debt resulting from adjustments from interest rate swaps entered into to hedge certain debt at Power and the unamortized premium resulting from a debt exchange entered into between Power and Energy Holdings.

[2] The debt fair valuation is based on the present value of each bond's future cash flows. The discount rates used in the present value analysis are based on an estimate of new issue bond yields across the treasury curve. When a bond has embedded options, an interest rate model is used to reflect the impact of interest rate volatility into the analysis. (primarily Level 2 measurements).

[3] Fair value amounts include $50 million of non-recourse project debt related to Dynegy which is classified as a Level 3 measurement. See "Fair Value Option" above for more details on Dynegy debt. Non-recourse project debt of $45 million is valued as equivalent to the amortized cost and is classified as a Level 3 measurement.