Trust Investments (Narrative) (Detail) $ in Millions	12 Months Ended
	Dec. 31, 2020 USD ($)
Nuclear Decommissioning Trust (NDT) Fund [Member] | PSEG Power LLC
Schedule of Trust Investments [Line Items]
NDT Fund Foreign Currency	$ 2
Decommissioning Liability, Noncurrent	852
Nuclear Decommissioning Trust (NDT) Fund [Member] | PSEG Power LLC | Minimum
Schedule of Trust Investments [Line Items]
Decommissioning Costs Including Contingencies	2,800
Nuclear Decommissioning Trust (NDT) Fund [Member] | PSEG Power LLC | Maximum [Member]
Schedule of Trust Investments [Line Items]
Decommissioning Costs Including Contingencies	3,000
Debt Securities [Member] | Nuclear Decommissioning Trust (NDT) Fund [Member] | PSEG Power LLC
Schedule of Trust Investments [Line Items]
Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, Net of Tax, Portion Attributable to Parent	37
Debt Securities [Member] | Rabbi Trust [Member]
Schedule of Trust Investments [Line Items]
Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, Net of Tax, Portion Attributable to Parent	13
Equity Securities [Member] | Nuclear Decommissioning Trust (NDT) Fund [Member] | PSEG Power LLC
Schedule of Trust Investments [Line Items]
Unrealized Gains (Losses) on Equity Securities still held	184
Equity Securities [Member] | Rabbi Trust [Member]
Schedule of Trust Investments [Line Items]
Unrealized Gains (Losses) on Equity Securities still held	$ 4