Trust Investments (Fair Value Of Rabbi Trust) (Detail) - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Schedule of Trust Investments [Line Items]
Total Rabbi Trust Investments	$ 261	$ 246
PSEG Power [Member]
Schedule of Trust Investments [Line Items]
Total Rabbi Trust Investments	65	62
Public Service Electric and Gas Company [Member]
Schedule of Trust Investments [Line Items]
Total Rabbi Trust Investments	51	48
Rabbi Trust [Member]
Schedule of Trust Investments [Line Items]
Total Rabbi Trust Investments	261	246
Rabbi Trust [Member] | PSEG Power [Member]
Schedule of Trust Investments [Line Items]
Total Rabbi Trust Investments	65	62
Rabbi Trust [Member] | Public Service Electric and Gas Company [Member]
Schedule of Trust Investments [Line Items]
Total Rabbi Trust Investments	51	48
Rabbi Trust [Member] | Other Entity [Member]
Schedule of Trust Investments [Line Items]
Total Rabbi Trust Investments	$ 145	$ 136