Trust Investments (Fair Values And Gross Unrealized Gains And Losses For The Securities Held) (Detail) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Mar. 31, 2021		Dec. 31, 2020
Nuclear Decommissioning Trust (NDT) Fund [Member] | PSEG Power [Member]
Schedule of Trust Investments [Line Items]
Trust Investments, Cost	$ 2,070		$ 1,990
Gross Unrealized Gains	482		523
Gross Unrealized Losses	(29)		(14)
Trust Investments, Fair Value	2,523	[1]	2,499	[2]
NDT Fund Foreign Currency	1		2
NDT Fund Cash excluded from Fair Value	1
Rabbi Trust [Member]
Schedule of Trust Investments [Line Items]
Trust Investments, Cost	227		238
Gross Unrealized Gains	17		28
Gross Unrealized Losses	(6)		0
Trust Investments, Fair Value	238		266
Total Debt Securities [Member] | Nuclear Decommissioning Trust (NDT) Fund [Member] | PSEG Power [Member]
Schedule of Trust Investments [Line Items]
Debt Securities, Available-for-sale, Amortized Cost	1,223		1,083
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	34		66
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	(20)		(2)
Debt Securities, Available-for-Sale, Fair Value	1,237		1,147
Total Debt Securities [Member] | Rabbi Trust [Member]
Schedule of Trust Investments [Line Items]
Debt Securities, Available-for-sale, Amortized Cost	209		217
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	7		18
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	(6)		0
Debt Securities, Available-for-Sale, Fair Value	210		235
Equity Securities [Member] | Nuclear Decommissioning Trust (NDT) Fund [Member] | PSEG Power [Member]
Schedule of Trust Investments [Line Items]
Equity Securities, Cost	847		907
Equity Securities, Accumulated Gross Unrealized Gain	448		457
Equity Securities, FV-NI, Unrealized Loss	(9)		(12)
Equity Securities, Fair Value	1,286		1,352
Corporate Debt Obligations [Member] | Nuclear Decommissioning Trust (NDT) Fund [Member] | PSEG Power [Member]
Schedule of Trust Investments [Line Items]
Debt Securities, Available-for-sale, Amortized Cost	587		528
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	21		39
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	(8)		(1)
Debt Securities, Available-for-Sale, Fair Value	600		566
Corporate Debt Obligations [Member] | Rabbi Trust [Member]
Schedule of Trust Investments [Line Items]
Debt Securities, Available-for-sale, Amortized Cost	109		123
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	5		12
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	(2)		0
Debt Securities, Available-for-Sale, Fair Value	112		135
Government Debt Securities [Member] | Nuclear Decommissioning Trust (NDT) Fund [Member] | PSEG Power [Member]
Schedule of Trust Investments [Line Items]
Debt Securities, Available-for-sale, Amortized Cost	636		555
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	13		27
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	(12)		(1)
Debt Securities, Available-for-Sale, Fair Value	637		581
Government Debt Securities [Member] | Rabbi Trust [Member]
Schedule of Trust Investments [Line Items]
Debt Securities, Available-for-sale, Amortized Cost	100		94
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	2		6
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	(4)		0
Debt Securities, Available-for-Sale, Fair Value	98		100
International Equity Securities [Member] | Nuclear Decommissioning Trust (NDT) Fund [Member] | PSEG Power [Member]
Schedule of Trust Investments [Line Items]
Equity Securities, Cost	365		388
Equity Securities, Accumulated Gross Unrealized Gain	140		152
Equity Securities, FV-NI, Unrealized Loss	(8)		(9)
Equity Securities, Fair Value	497		531
Domestic Equity Securities [Member] | Nuclear Decommissioning Trust (NDT) Fund [Member] | PSEG Power [Member]
Schedule of Trust Investments [Line Items]
Equity Securities, Cost	482		519
Equity Securities, Accumulated Gross Unrealized Gain	308		305
Equity Securities, FV-NI, Unrealized Loss	(1)		(3)
Equity Securities, Fair Value	789		821
Domestic Equity Securities [Member] | Rabbi Trust [Member]
Schedule of Trust Investments [Line Items]
Equity Securities, Cost	18		21
Equity Securities, Accumulated Gross Unrealized Gain	10		10
Equity Securities, FV-NI, Unrealized Loss	0		0
Equity Securities, Fair Value	$ 28		$ 31

[1] The NDT Fund Investments table excludes cash of $1 million and foreign currency of $1 million as of March 31, 2021, which are part of the NDT Fund.

[2] The NDT Fund Investments table excludes foreign currency of $2 million as of December 31, 2020, which is part of the NDT Fund.