Pension, OPEB and Savings Plans (Narrative) (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Defined Benefit Plan Disclosure [Line Items]
Pension and Other Postretirement Defined Benefit Plans, Liabilities, Noncurrent	$ 126,000,000	$ 0
Number of PSEG's defined contribution plans	2
Historical annualized rate of return	9.50%
Defined Benefit Plans, Estimated Future Employer Contributions in Next Fiscal Year	25,000,000
Defined benefit plan funded status of plan percentage	93.00%
Rabbi trust assets used to fund nonqualified pension plans	191,000,000
Defined benefit plans, projected benefit and accumulated benefit obligations	5,500,000,000	4,500,000,000
PSEG expected contribution to postretirement healthcare plan for calendar year 2014	14,000,000
Maximum annual 401(k) contribution per employee, percent	50.00%
Defined Contribution Plan, Employer Matching Contribution, Percent of Match	50.00%
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Impact of Mortality Table Change in Actuarial (Gain) Loss	314,000,000
Accumulated Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Net of Tax	411,000,000	238,000,000
Accumulated Other Comprehensive Income (Loss), Defined Benefit Pension and Other Postretirement Plans, Before Tax	702,000,000	408,000,000
Defined Benefit Plan, Net Periodic Benefit Cost	(23,000,000)	152,000,000	167,000,000
Pension and Other Postretirement Defined Benefit Plans, Liabilities, Noncurrent	440,000,000	121,000,000
Expected long-term rate of return on plan assets	8.00%	8.00%	8.00%
Interest in Master Trust assets percentage	94.00%
Other Pension Plan, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Benefit Obligation	161,000,000
Other Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Impact of Mortality Table Change in Actuarial (Gain) Loss	79,000,000
Defined Benefit Plan, Net Periodic Benefit Cost	70,000,000	91,000,000	84,000,000
Pension and Other Postretirement Defined Benefit Plans, Liabilities, Noncurrent	1,277,000,000	1,095,000,000
Expected long-term rate of return on plan assets	8.00%	8.00%	8.00%
Interest in Master Trust assets percentage		6.00%
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] | Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Net Periodic Benefit Cost	(7,000,000)	43,000,000	52,000,000
Power [Member] | Other Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Net Periodic Benefit Cost	20,000,000	23,000,000	18,000,000
Thrift Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Employer matching contribution, percent	8.00%
Long Island Electric Utility Servco LLC Pension and OPEB [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Net Periodic Benefit Cost	67,000,000
Number of PSEG's defined contribution plans	2
Historical annualized rate of return	6.30%
Defined Benefit Plans, Estimated Future Employer Contributions in Next Fiscal Year	30,000,000
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%
Long Island Electric Utility Servco LLC Pension and OPEB [Member] | Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Pension and Other Postretirement Defined Benefit Plans, Liabilities, Noncurrent	0
Expected long-term rate of return on plan assets	7.70%
Long Island Electric Utility Servco LLC Pension and OPEB [Member] | Other Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Pension and Other Postretirement Defined Benefit Plans, Liabilities, Noncurrent	$ 452,000,000
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%
Savings Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Employer matching contribution, percent	7.00%