Accumulated Other Comprehensive Income (Loss), Net of Tax (Reclassifications of AOCI) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax	$ (2)	$ (12)	$ (8)	$ (27)
Reclassification from Accumulated Other Comprehensive Income, Current Period, Tax	1	4	3	9
Amounts Reclassified from Accumulated Other Comprehensive Income (Loss)	(1)	(8)	(5)	(18)
Cash Flow Hedges [Member]
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, before Tax	(1)		(1)		$ 0
Amounts Reclassified from Accumulated Other Comprehensive Income (Loss)	0	0	0	0	$ 0
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, Tax	(1)		(1)
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, Net of Tax	0		0
Pension and OPEB Plans [Member]
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Reclassification Adjustment from AOCI, Pension and OPEB, Pre-Tax	(5)	(10)	(10)	(21)
Reclassification Adjustment from AOCI, Pension and OPEB, Tax	1	3	3	6
Reclassification Adjustment from AOCI, Pension and OPEB, After-Tax	(4)	(7)	(7)	(15)
Amounts Reclassified from Accumulated Other Comprehensive Income (Loss)	(4)	(7)	(7)	(15)
Available-for-Sale Securities [Member]
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Reclassification for Available for Sale Securities, Pre-Tax	4	(2)	3	(6)
Reclassification for Available for Sale Securities, Tax	(1)	1	(1)	3
Reclassification for Available for Sale Securities, After-Tax	3	(1)	2	(3)
Amounts Reclassified from Accumulated Other Comprehensive Income (Loss)	3	(1)	2	(3)
PSEG Power [Member]
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax	(1)	(10)	(6)	(23)
Reclassification from Accumulated Other Comprehensive Income, Current Period, Tax	0	3	1	8
Amounts Reclassified from Accumulated Other Comprehensive Income (Loss)	(1)	(7)	(5)	(15)
PSEG Power [Member] | Cash Flow Hedges [Member]
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Amounts Reclassified from Accumulated Other Comprehensive Income (Loss)	0	0	0	0
PSEG Power [Member] | Pension and OPEB Plans [Member]
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Reclassification Adjustment from AOCI, Pension and OPEB, Pre-Tax	(4)	(8)	(8)	(17)
Reclassification Adjustment from AOCI, Pension and OPEB, Tax	1	2	2	5
Reclassification Adjustment from AOCI, Pension and OPEB, After-Tax	(3)	(6)	(6)	(12)
Amounts Reclassified from Accumulated Other Comprehensive Income (Loss)	(3)	(6)	(6)	(12)
PSEG Power [Member] | Available-for-Sale Securities [Member]
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Reclassification for Available for Sale Securities, Pre-Tax	3	(2)	2	(6)
Reclassification for Available for Sale Securities, Tax	(1)	1	(1)	3
Reclassification for Available for Sale Securities, After-Tax	2	(1)	1	(3)
Amounts Reclassified from Accumulated Other Comprehensive Income (Loss)	2	(1)	1	(3)
Interest Expense [Member] | Cash Flow Hedges [Member]
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, before Tax	(1)		(1)
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, Tax	(1)		(1)
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, Net of Tax	0		0
Non-Operating Pension and OPEB Credits (Costs) [Member] | Pension and OPEB Plans [Member]
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Amortization of Prior Service (Cost) Credit, Pre-Tax			13	2
Amortization of Prior Service (Cost) Credit, Tax			(4)	0
Amortization of Prior Service (Cost) Credit, After-Tax			9	2
Amortization of Actuarial Loss, Pre-Tax			(23)	(23)
Amortization of Actuarial Loss, Tax			7	6
Amortization of Actuarial Loss, After-Tax			(16)	(17)
Non-Operating Pension and OPEB Credits (Costs) [Member] | PSEG Power [Member] | Pension and OPEB Plans [Member]
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Amortization of Prior Service (Cost) Credit, Pre-Tax			11	2
Amortization of Prior Service (Cost) Credit, Tax			(3)	0
Amortization of Prior Service (Cost) Credit, After-Tax			8	2
Amortization of Actuarial Loss, Pre-Tax			(19)	(19)
Amortization of Actuarial Loss, Tax			5	5
Amortization of Actuarial Loss, After-Tax			(14)	(14)
Operating Expense [Member] | Pension and OPEB Plans [Member]
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Amortization of Prior Service (Cost) Credit, Pre-Tax	6	1
Amortization of Prior Service (Cost) Credit, Tax	(2)	0
Amortization of Prior Service (Cost) Credit, After-Tax	4	1
Amortization of Actuarial Loss, Pre-Tax	(11)	(11)
Amortization of Actuarial Loss, Tax	3	3
Amortization of Actuarial Loss, After-Tax	(8)	(8)
Operating Expense [Member] | PSEG Power [Member] | Pension and OPEB Plans [Member]
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Amortization of Prior Service (Cost) Credit, Pre-Tax	5	1
Amortization of Prior Service (Cost) Credit, Tax	(1)	0
Amortization of Prior Service (Cost) Credit, After-Tax	4	1
Amortization of Actuarial Loss, Pre-Tax	(9)	(9)
Amortization of Actuarial Loss, Tax	2	2
Amortization of Actuarial Loss, After-Tax	(7)	(7)
Other Income [Member] | Available-for-Sale Securities [Member]
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Reclassification for Available for Sale Securities, Pre-Tax	4	(2)
Reclassification for Available for Sale Securities, Tax	(1)	1
Reclassification for Available for Sale Securities, After-Tax	3	(1)
Other Income [Member] | PSEG Power [Member] | Available-for-Sale Securities [Member]
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Reclassification for Available for Sale Securities, Pre-Tax	3	(2)
Reclassification for Available for Sale Securities, Tax	(1)	1
Reclassification for Available for Sale Securities, After-Tax	$ 2	$ (1)
Net Gains (Losses) on Trust Investments [Member] | Available-for-Sale Securities [Member]
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Reclassification for Available for Sale Securities, Pre-Tax			3	(6)
Reclassification for Available for Sale Securities, Tax			(1)	3
Reclassification for Available for Sale Securities, After-Tax			2	(3)
Net Gains (Losses) on Trust Investments [Member] | PSEG Power [Member] | Available-for-Sale Securities [Member]
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Reclassification for Available for Sale Securities, Pre-Tax			2	(6)
Reclassification for Available for Sale Securities, Tax			(1)	3
Reclassification for Available for Sale Securities, After-Tax			$ 1	$ (3)