Financial Risk Management Activities (Schedule Of Gross Volume On Absolute Basis For Derivative Contracts) (Details)	Dec. 31, 2011	Dec. 31, 2010
Natural Gas Dth [Member]
Derivative [Line Items]
Gross volume of derivative on absolute value basis	612,000,000	704,000,000
Electricity MWh [Member]
Derivative [Line Items]
Gross volume of derivative on absolute value basis	137,000,000	154,000,000
Capacity MW Days [Member]
Derivative [Line Items]
Gross volume of derivative on absolute value basis		1,000,000
FTRs MWh [Member]
Derivative [Line Items]
Gross volume of derivative on absolute value basis	12,000,000	23,000,000
Interest Rate Swaps [Member]
Derivative [Line Items]
Gross volume of derivative on absolute value basis	1,100,000,000	1,150,000,000
Coal Tons [Member]
Derivative [Line Items]
Gross volume of derivative on absolute value basis	1,000,000
Coal Tons [Member] | PSEG [Member]
Derivative [Line Items]
Gross volume of derivative on absolute value basis	0
Coal Tons [Member] | Power [Member]
Derivative [Line Items]
Gross volume of derivative on absolute value basis	1,000,000
Coal Tons [Member] | PSE&G [Member]
Derivative [Line Items]
Gross volume of derivative on absolute value basis	0
Natural Gas Dth In Millions [Member] | PSEG [Member]
Derivative [Line Items]
Gross volume of derivative on absolute value basis	0	0
Natural Gas Dth In Millions [Member] | Power [Member]
Derivative [Line Items]
Gross volume of derivative on absolute value basis	377,000,000	424,000,000
Natural Gas Dth In Millions [Member] | PSE&G [Member]
Derivative [Line Items]
Gross volume of derivative on absolute value basis	235,000,000	280,000,000
Electricity MWh In Millions [Member] | PSEG [Member]
Derivative [Line Items]
Gross volume of derivative on absolute value basis	0	0
Electricity MWh In Millions [Member] | Power [Member]
Derivative [Line Items]
Gross volume of derivative on absolute value basis	137,000,000	154,000,000
Electricity MWh In Millions [Member] | PSE&G [Member]
Derivative [Line Items]
Gross volume of derivative on absolute value basis	0	0
Capacity MW Days In Millions [Member] | PSEG [Member]
Derivative [Line Items]
Gross volume of derivative on absolute value basis		0
Capacity MW Days In Millions [Member] | Power [Member]
Derivative [Line Items]
Gross volume of derivative on absolute value basis		1,000,000
Capacity MW Days In Millions [Member] | PSE&G [Member]
Derivative [Line Items]
Gross volume of derivative on absolute value basis		0
FTRs MWh In Millions [Member] | PSEG [Member]
Derivative [Line Items]
Gross volume of derivative on absolute value basis	0	0
FTRs MWh In Millions [Member] | Power [Member]
Derivative [Line Items]
Gross volume of derivative on absolute value basis	12,000,000	23,000,000
FTRs MWh In Millions [Member] | PSE&G [Member]
Derivative [Line Items]
Gross volume of derivative on absolute value basis	0	0
Interest Rate Swaps USD In Millions [Member] | PSEG [Member]
Derivative [Line Items]
Gross volume of derivative on absolute value basis	1,100,000,000	1,150,000,000
Interest Rate Swaps USD In Millions [Member] | Power [Member]
Derivative [Line Items]
Gross volume of derivative on absolute value basis	0	0
Interest Rate Swaps USD In Millions [Member] | PSE&G [Member]
Derivative [Line Items]
Gross volume of derivative on absolute value basis	0	0