Financial Risk Management Activities (Schedule Of Gross Volume, On Absolute Basis For Derivative Contracts) (Detail)	Sep. 30, 2012	Dec. 31, 2011
Natural Gas Dth [Member]
Derivative [Line Items]
Gross volume of derivative on absolute value basis	588,000,000	612,000,000
Electricity MWh [Member]
Derivative [Line Items]
Gross volume of derivative on absolute value basis	179,000,000	137,000,000
Capacity MW Days [Member]
Derivative [Line Items]
Gross volume of derivative on absolute value basis	4,000,000
FTRs MWh [Member]
Derivative [Line Items]
Gross volume of derivative on absolute value basis	28,000,000	12,000,000
Interest Rate Swaps [Member]
Derivative [Line Items]
Gross volume of derivative on absolute value basis	1,100,000,000	1,100,000,000
Coal Tons [Member]
Derivative [Line Items]
Gross volume of derivative on absolute value basis	1,000,000	1,000,000
PSEG [Member] | Natural Gas Dth [Member]
Derivative [Line Items]
Gross volume of derivative on absolute value basis	0	0
PSEG [Member] | Electricity MWh [Member]
Derivative [Line Items]
Gross volume of derivative on absolute value basis	0	0
PSEG [Member] | Capacity MW Days [Member]
Derivative [Line Items]
Gross volume of derivative on absolute value basis	0
PSEG [Member] | FTRs MWh [Member]
Derivative [Line Items]
Gross volume of derivative on absolute value basis	0	0
PSEG [Member] | Interest Rate Swaps [Member]
Derivative [Line Items]
Gross volume of derivative on absolute value basis	1,100,000,000	1,100,000,000
PSEG [Member] | Coal Tons [Member]
Derivative [Line Items]
Gross volume of derivative on absolute value basis	0	0
Power [Member] | Natural Gas Dth [Member]
Derivative [Line Items]
Gross volume of derivative on absolute value basis	385,000,000	377,000,000
Power [Member] | Electricity MWh [Member]
Derivative [Line Items]
Gross volume of derivative on absolute value basis	179,000,000	137,000,000
Power [Member] | Capacity MW Days [Member]
Derivative [Line Items]
Gross volume of derivative on absolute value basis	0
Power [Member] | FTRs MWh [Member]
Derivative [Line Items]
Gross volume of derivative on absolute value basis	28,000,000	12,000,000
Power [Member] | Interest Rate Swaps [Member]
Derivative [Line Items]
Gross volume of derivative on absolute value basis	0	0
Power [Member] | Coal Tons [Member]
Derivative [Line Items]
Gross volume of derivative on absolute value basis	1,000,000	1,000,000
PSE And G [Member] | Natural Gas Dth [Member]
Derivative [Line Items]
Gross volume of derivative on absolute value basis	203,000,000	235,000,000
PSE And G [Member] | Electricity MWh [Member]
Derivative [Line Items]
Gross volume of derivative on absolute value basis	0	0
PSE And G [Member] | Capacity MW Days [Member]
Derivative [Line Items]
Gross volume of derivative on absolute value basis	4,000,000
PSE And G [Member] | FTRs MWh [Member]
Derivative [Line Items]
Gross volume of derivative on absolute value basis	0	0
PSE And G [Member] | Interest Rate Swaps [Member]
Derivative [Line Items]
Gross volume of derivative on absolute value basis	0	0
PSE And G [Member] | Coal Tons [Member]
Derivative [Line Items]
Gross volume of derivative on absolute value basis	0	0