Trust Investments (Narrative) (Detail) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020 USD ($)	Sep. 30, 2019 USD ($)	Sep. 30, 2020 USD ($) Facility		Sep. 30, 2019 USD ($)	Dec. 31, 2019 USD ($)
PSEG Power [Member]
Schedule of Trust Investments [Line Items]
Number of Nuclear Facilities | Facility			5
Nuclear Decommissioning Trust (NDT) Fund [Member] | PSEG Power [Member]
Schedule of Trust Investments [Line Items]
NDT Fund Foreign Currency	$ 1		$ 1			$ 2
Impairment of Debt Securities	0	$ 0	(3)	[1]	$ 0
Debt Securities [Member] | Nuclear Decommissioning Trust (NDT) Fund [Member] | PSEG Power [Member]
Schedule of Trust Investments [Line Items]
After tax amount of net unrealized gains recognized in AOCI			36
Debt Securities [Member] | Rabbi Trust [Member]
Schedule of Trust Investments [Line Items]
After tax amount of net unrealized gains recognized in AOCI			13
Equity Securities [Member] | Nuclear Decommissioning Trust (NDT) Fund [Member] | PSEG Power [Member]
Schedule of Trust Investments [Line Items]
Unrealized Gains (Losses) on Equity Securities still held	48		48
Equity Securities [Member] | Rabbi Trust [Member]
Schedule of Trust Investments [Line Items]
Unrealized Gains (Losses) on Equity Securities still held	$ 2		$ 1

[1] PSEG Power recognized an impairment of available-for-sale debt securities that it intends to sell. PSEG Power’s policy is to sell all such securities that are rated below investment grade.