Financial Risk Management Activities (Schedule Of Derivative Transactions Designated And Effective As Cash Flow Hedges) (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Unrealized Gain (Loss) on Cash Flow Hedging Instruments	$ 0	$ 0	$ 0	$ (6)
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion	(1)	(5)	(3)	(11)
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	(2)	0	(8)	6
Cash Flow Hedges [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	(1)	(4)	(2)	(8)	$ (10)
PSEG Power [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	(1)	3	(4)	11
PSEG Power [Member] | Cash Flow Hedges [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	0	0	0	0
Interest Expense [Member] | Interest Rate Swap [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Unrealized Gain (Loss) on Cash Flow Hedging Instruments	0	0	0	(6)
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion	$ (1)	$ (5)	$ (3)	$ (11)