Pension, OPEB and Savings Plans (Narrative) (Details) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018 USD ($) plan	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Defined Benefit Plan Disclosure [Line Items]
Number of PSEG's defined contribution plans | plan		2
Defined benefit plan funded status of plan percentage		86.00%
Rabbi trust assets used to fund nonqualified pension plans		$ 224
Defined benefit plans, projected benefit and accumulated benefit obligations		5,700	$ 6,100
OPEB Plan estimated contribution in next fiscal year		$ 10
Maximum annual 401(k) contribution per employee, percent		50.00%
Defined Contribution Plan, Employer Matching Contribution, Percent of Match		50.00%
Total Employer Matching Contributions		$ 41	41	$ 41
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Accumulated Other Comprehensive (Income) Loss, Defined Benefit Plan, after Tax		360	406
Accumulated Other Comprehensive Income (Loss), Defined Benefit Pension and Other Postretirement Plans, Before Tax		619	683
Defined Benefit Plan, Net Periodic Benefit Cost (Credit)		$ (36)	$ 3	$ 56
Expected long-term rate of return on plan assets		7.80%	7.80%	8.00%
Interest in Master Trust assets percentage		91.00%
Defined Benefit Plan, Benefit Obligation, Increase (Decrease) for Plan Amendment		$ 0	$ 0
Other Pension Plan, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Benefit Obligation		156
Other Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Net Periodic Benefit Cost (Credit)		$ 106	$ 86	$ 71
Expected long-term rate of return on plan assets		7.80%	7.80%	8.00%
Interest in Master Trust assets percentage			9.00%
Defined Benefit Plan, Benefit Obligation, Increase (Decrease) for Plan Amendment		$ 559	$ 0
Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Target allocation percentage of assets		70.00%
Fixed Income Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Target allocation percentage of assets		30.00%
Power [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Employer Matching Contributions		$ 10	11	$ 12
Power [Member] | Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Net Periodic Benefit Cost (Credit)		(9)	1	16
Power [Member] | Other Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Net Periodic Benefit Cost (Credit)		$ 32	27	23
Thrift Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Employer matching contribution, percent		8.00%
Savings Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Employer matching contribution, percent		7.00%
Long Island Electric Utility Servco LLC Pension and OPEB [Member]
Defined Benefit Plan Disclosure [Line Items]
Number of PSEG's defined contribution plans | plan		2
Defined Benefit Plan, Expected Future Employer Contributions, Next Fiscal Year		$ 28
Maximum annual 401(k) contribution per employee, percent		50.00%
Defined Contribution Plan, Employer Matching Contribution, Percent of Match		50.00%
Employer matching contribution, percent		8.00%
Total Employer Matching Contributions		$ 7	6	5
Long Island Electric Utility Servco LLC Pension and OPEB [Member] | Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Net Periodic Benefit Cost (Credit)		$ 40	35	28
Expected long-term rate of return on plan assets		7.60%
Defined Benefit Plan, Benefit Obligation, Increase (Decrease) for Plan Amendment		$ 0	0
Long Island Electric Utility Servco LLC Pension and OPEB [Member] | Other Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Net Periodic Benefit Cost (Credit)		6	4	$ 2
Defined Benefit Plan, Benefit Obligation, Increase (Decrease) for Plan Amendment		$ 0	$ 0
Long Island Electric Utility Servco LLC Pension and OPEB [Member] | Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Target allocation percentage of assets		70.00%
Long Island Electric Utility Servco LLC Pension and OPEB [Member] | Fixed Income Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Target allocation percentage of assets		30.00%
Subsequent Event [Member] | Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Expected long-term rate of return on plan assets	7.80%
Subsequent Event [Member] | Long Island Electric Utility Servco LLC Pension and OPEB [Member] | Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Expected long-term rate of return on plan assets	7.60%