Financial Risk Management Activities (Schedule Of Gross Volume, On Absolute Basis For Derivative Contracts) (Detail) $ / mwh in Millions, $ / DTH in Millions	9 Months Ended	12 Months Ended
	Sep. 30, 2018 $ / mwh $ / DTH	Dec. 31, 2017 $ / mwh $ / DTH
Natural Gas Dth [Member]
Derivative [Line Items]
Gross Volume of Derivative on Absolute Value Basis | $ / DTH	281	154
Electricity MWh [Member]
Derivative [Line Items]
Gross Volume of Derivative on Absolute Value Basis	(66)	(63)
FTRs MWh [Member]
Derivative [Line Items]
Gross Volume of Derivative on Absolute Value Basis	24	6
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] | FTRs MWh [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 | $ / DTH	281	154
Power [Member] | Electricity MWh [Member]
Derivative [Line Items]
Gross Volume of Derivative on Absolute Value Basis	(66)	(63)
Power [Member] | FTRs MWh [Member]
Derivative [Line Items]
Gross Volume of Derivative on Absolute Value Basis	24	6
PSE And G [Member] | Natural Gas Dth [Member]
Derivative [Line Items]
Gross Volume of Derivative on Absolute Value Basis | $ / DTH	0	0
PSE And G [Member] | Electricity MWh [Member]
Derivative [Line Items]
Gross Volume of Derivative on Absolute Value Basis	0	0
PSE And G [Member] | FTRs MWh [Member]
Derivative [Line Items]
Gross Volume of Derivative on Absolute Value Basis	0	0