Trust Investments (Amount Of Available-For-Sale Debt Securities By Maturity Periods) (Detail) $ in Millions	Sep. 30, 2020 USD ($)
Rabbi Trust [Member]
Schedule of Trust Investments [Line Items]
Total Available-for-Sale Debt Securities	$ 234
PSEG Power [Member] \| Nuclear Decommissioning Trust (NDT) Fund [Member]
Schedule of Trust Investments [Line Items]
Total Available-for-Sale Debt Securities	1,139
Debt Securities [Member] \| Rabbi Trust [Member]
Schedule of Trust Investments [Line Items]
Less than one year	0
1 - 5 years	35
6 - 10 years	35
11 - 15 years	14
16 - 20 years	32
Over 20 years	118
Debt Securities [Member] \| PSEG Power [Member] \| Nuclear Decommissioning Trust (NDT) Fund [Member]
Schedule of Trust Investments [Line Items]
Less than one year	25
1 - 5 years	276
6 - 10 years	205
11 - 15 years	79
16 - 20 years	76
Over 20 years	$ 478

Available For Sale Securities Debt Maturities After Fifteen Through Twenty Years Fair Value

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