Financial Risk Management Activities (Schedule Providing Credit Risk From Others, Net Of Collateral) (Detail) - PSEG Power [Member] $ in Millions	9 Months Ended
	Sep. 30, 2020 USD ($) Counterparty
Derivative [Line Items]
Current Exposure	$ 246
Securities held as Collateral	34
Net exposure	212
Number of Counterparties greater than 10%	$ 3
Number Of Active Counterparties On Credit Risk Derivatives | Counterparty	128
Investment Grade - External Rating [Member]
Derivative [Line Items]
Percentage Of Credit Exposure	99.00%
Investment Grade [Member]
Derivative [Line Items]
Current Exposure	$ 244
Securities held as Collateral	34
Net exposure	210
Number of Counterparties greater than 10%	3
Amount Of Net Credit Exposure Greater Than Ten Percent	120
External Credit Rating, Non Investment Grade [Member]
Derivative [Line Items]
Current Exposure	2
Securities held as Collateral	0
Amount Of Net Credit Exposure Greater Than Ten Percent	0
Non-Investment Grade [Member]
Derivative [Line Items]
Net exposure	2
Number of Counterparties greater than 10%	0
Cash [Member]
Derivative [Line Items]
Securities held as Collateral	1
Letter of Credit [Member]
Derivative [Line Items]
Securities held as Collateral	33
Other Entities [Member] | Investment Grade [Member]
Derivative [Line Items]
Amount Of Net Credit Exposure Greater Than Ten Percent	70
Public Service Electric and Gas Company [Member] | Investment Grade [Member]
Derivative [Line Items]
Amount Of Net Credit Exposure Greater Than Ten Percent	$ 50