Financial Risk Management Activities (Schedule Of Net Notional Volume For Open Derivative Contracts) (Detail) $ / mwh in Millions, $ / Derivative in Millions, $ / DTH in Millions	9 Months Ended	12 Months Ended
	Sep. 30, 2020 $ / Derivative $ / mwh $ / DTH	Dec. 31, 2019 $ / mwh $ / Derivative $ / DTH
Natural Gas Dth [Member]
Derivative [Line Items]
Net notional volume of derivative transactions | $ / DTH	266	341
Electricity MWh [Member]
Derivative [Line Items]
Net notional volume of derivative transactions	(58)	(62)
FTRs MWh [Member]
Derivative [Line Items]
Net notional volume of derivative transactions	26	13
Interest Rate Swaps [Member]
Derivative [Line Items]
Net notional volume of derivative transactions | $ / Derivative	700	700
PSEG [Member] | Natural Gas Dth [Member]
Derivative [Line Items]
Net notional volume of derivative transactions	0	0
PSEG [Member] | Electricity MWh [Member]
Derivative [Line Items]
Net notional volume of derivative transactions	0	0
PSEG [Member] | FTRs MWh [Member]
Derivative [Line Items]
Net notional volume of derivative transactions	0	0
PSEG [Member] | Interest Rate Swaps [Member]
Derivative [Line Items]
Net notional volume of derivative transactions | $ / Derivative	700	700
PSEG Power [Member] | Natural Gas Dth [Member]
Derivative [Line Items]
Net notional volume of derivative transactions | $ / DTH	266	341
PSEG Power [Member] | Electricity MWh [Member]
Derivative [Line Items]
Net notional volume of derivative transactions	(58)	(62)
PSEG Power [Member] | FTRs MWh [Member]
Derivative [Line Items]
Net notional volume of derivative transactions	26	13
PSEG Power [Member] | Interest Rate Swaps [Member]
Derivative [Line Items]
Net notional volume of derivative transactions | $ / Derivative	0	0
Public Service Electric and Gas Company [Member] | Natural Gas Dth [Member]
Derivative [Line Items]
Net notional volume of derivative transactions | $ / DTH	0	0
Public Service Electric and Gas Company [Member] | Electricity MWh [Member]
Derivative [Line Items]
Net notional volume of derivative transactions	0	0
Public Service Electric and Gas Company [Member] | FTRs MWh [Member]
Derivative [Line Items]
Net notional volume of derivative transactions	0	0
Public Service Electric and Gas Company [Member] | Interest Rate Swaps [Member]
Derivative [Line Items]
Net notional volume of derivative transactions | $ / Derivative	0	0