Trust Investments (Fair Value Of Rabbi Trust) (Detail) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Schedule of Trust Investments [Line Items]
Total Rabbi Trust Investments	$ 244	$ 246
PSEG Power [Member]
Schedule of Trust Investments [Line Items]
Total Rabbi Trust Investments	61	62
Public Service Electric and Gas Company [Member]
Schedule of Trust Investments [Line Items]
Total Rabbi Trust Investments	47	48
Rabbi Trust [Member]
Schedule of Trust Investments [Line Items]
Total Rabbi Trust Investments	244	246
Rabbi Trust [Member] | PSEG Power [Member]
Schedule of Trust Investments [Line Items]
Total Rabbi Trust Investments	61	62
Rabbi Trust [Member] | Public Service Electric and Gas Company [Member]
Schedule of Trust Investments [Line Items]
Total Rabbi Trust Investments	47	48
Rabbi Trust [Member] | Other Entity [Member]
Schedule of Trust Investments [Line Items]
Total Rabbi Trust Investments	$ 136	$ 136