Financial Risk Management Activities (Schedule Providing Credit Risk From Others, Net Of Collateral) (Detail) - PSEG Power [Member] $ in Millions	3 Months Ended
	Mar. 31, 2021 USD ($) Counterparty
Derivative [Line Items]
Current Exposure	$ 275
Securities held as Collateral	37
Net exposure	238
Number of Counterparties greater than 10%	$ 1
Number Of Active Counterparties On Credit Risk Derivatives | Counterparty	131
Investment Grade - External Rating [Member]
Derivative [Line Items]
Percentage Of Credit Exposure	91.00%
Investment Grade [Member]
Derivative [Line Items]
Current Exposure	$ 234
Securities held as Collateral	18
Net exposure	216
Number of Counterparties greater than 10%	1
Amount Of Net Credit Exposure Greater Than Ten Percent	121
External Credit Rating, Non Investment Grade [Member]
Derivative [Line Items]
Current Exposure	41
Securities held as Collateral	19
Amount Of Net Credit Exposure Greater Than Ten Percent	0
Non-Investment Grade [Member]
Derivative [Line Items]
Net exposure	22
Number of Counterparties greater than 10%	0
Cash [Member]
Derivative [Line Items]
Securities held as Collateral	3
Letter of Credit [Member]
Derivative [Line Items]
Securities held as Collateral	34
Public Service Electric and Gas Company [Member] | Investment Grade [Member]
Derivative [Line Items]
Amount Of Net Credit Exposure Greater Than Ten Percent	$ 121