Pension And OPEB (Narrative) (Detail) - USD ($) $ in Millions	3 Months Ended			6 Months Ended
	Sep. 30, 2023	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Minimum [Member] | Subsequent Event [Member]
Defined Benefit Plan Disclosure [Line Items]
Pension Lift Out Settlement Charge	$ 315
Pension Lift Out Settlement Charge, net of tax	225
Maximum [Member] | Subsequent Event [Member]
Defined Benefit Plan Disclosure [Line Items]
Pension Lift Out Settlement Charge	360
Pension Lift Out Settlement Charge, net of tax	$ 260
Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Benefit Costs		$ 20	$ (29)	$ 40	$ (58)
Pension Plan [Member] | Public Service Electric and Gas Company [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Benefit Costs		14	(17)	27	(35)
Postretirement Healthcare Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Benefit Costs		(10)	(31)	(21)	(62)
Postretirement Healthcare Plans [Member] | Public Service Electric and Gas Company [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Benefit Costs		(10)	(28)	(20)	(55)
Long Island Electric Utility Servco LLC Pension and OPEB [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Expected Future Employer Contributions, Current Fiscal Year		18		18
Long Island Electric Utility Servco LLC Pension and OPEB [Member] | Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Benefit Costs		4	7	9	15
Long Island Electric Utility Servco LLC Pension and OPEB [Member] | Postretirement Healthcare Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Benefit Costs		$ 3	$ 3	$ 6	$ 5