Financial Risk Management Activities (Schedule Providing Credit Risk From Others, Net Of Collateral) (Detail) $ in Millions	9 Months Ended
	Sep. 30, 2021 USD ($) Counterparty
PSEG Power [Member]
Derivative [Line Items]
Current Exposure	$ 154
Securities held as Collateral	15
Net exposure	139
Number of Counterparties greater than 10%	$ 2
Number Of Active Counterparties On Credit Risk Derivatives | Counterparty	114
PSEG Power [Member] | Investment Grade - External Rating [Member]
Derivative [Line Items]
Percentage Of Credit Exposure	96.00%
PSEG Power [Member] | Investment Grade [Member]
Derivative [Line Items]
Current Exposure	$ 147
Securities held as Collateral	14
Net exposure	133
Number of Counterparties greater than 10%	2
Amount Of Net Credit Exposure Greater Than Ten Percent	38
PSEG Power [Member] | External Credit Rating, Non Investment Grade [Member]
Derivative [Line Items]
Current Exposure	7
Securities held as Collateral	1
Amount Of Net Credit Exposure Greater Than Ten Percent	0
PSEG Power [Member] | Non-Investment Grade [Member]
Derivative [Line Items]
Net exposure	6
Number of Counterparties greater than 10%	0
Public Service Electric and Gas Company [Member]
Derivative [Line Items]
Current Exposure	233
Letter of Credit [Member] | PSEG Power [Member]
Derivative [Line Items]
Securities held as Collateral	15
Public Service Electric and Gas Company [Member] | PSEG Power [Member] | Investment Grade [Member]
Derivative [Line Items]
Amount Of Net Credit Exposure Greater Than Ten Percent	21
Non affiliated counterparties | PSEG Power [Member] | Investment Grade [Member]
Derivative [Line Items]
Amount Of Net Credit Exposure Greater Than Ten Percent	17
PSEG Power [Member] | Public Service Electric and Gas Company [Member]
Derivative [Line Items]
Current Exposure	$ 18