Income Taxes (Unrecognized Tax Benefits) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
PSEG [Member]
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Total Amount of Unrecognized Tax Benefits at January	$ 825	$ 756	$ 836
Increases as a Result of Positions Taken in a Prior Period	92	58	290
Decreases as a Result of Positions Taken in a Prior Period	(173)	(22)	(450)
Increases as a Result of Positions Taken during the Current Period	47	37	82
Decreases as a Result of Positions Taken during the Current Period	0	(4)	(2)
Decreases as a Result of Settlements with Taxing Authorities	(389)	0	0
Decreases due to Lapses of Applicable Statute of Limitations	0	0	0
Total Amount of Unrecognized Tax Benefits at December	402	825	756
Accumulated Deferred Income Taxes Associated with Unrecognized Tax Benefits	(264)	(379)	(332)
Regulatory Asset-Unrecognized Tax Benefits	(30)	(20)	(16)
Amount of unrecognized tax benefits that would affect the effective tax rate	108	426	408
Power [Member]
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Total Amount of Unrecognized Tax Benefits at January	121	101	(42)
Increases as a Result of Positions Taken in a Prior Period	27	24	111
Decreases as a Result of Positions Taken in a Prior Period	(7)	(9)	(29)
Increases as a Result of Positions Taken during the Current Period	3	8	63
Decreases as a Result of Positions Taken during the Current Period	0	(3)	(2)
Decreases as a Result of Settlements with Taxing Authorities	(10)	0	0
Decreases due to Lapses of Applicable Statute of Limitations	0	0	0
Total Amount of Unrecognized Tax Benefits at December	134	121	101
Accumulated Deferred Income Taxes Associated with Unrecognized Tax Benefits	(93)	(77)	(67)
Regulatory Asset-Unrecognized Tax Benefits	0	0	0
Amount of unrecognized tax benefits that would affect the effective tax rate	41	44	34
PSE&G [Member]
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Total Amount of Unrecognized Tax Benefits at January	113	82	35
Increases as a Result of Positions Taken in a Prior Period	55	14	79
Decreases as a Result of Positions Taken in a Prior Period	(47)	0	(38)
Increases as a Result of Positions Taken during the Current Period	42	18	6
Decreases as a Result of Positions Taken during the Current Period	0	(1)	0
Decreases as a Result of Settlements with Taxing Authorities	0	0	0
Decreases due to Lapses of Applicable Statute of Limitations	0	0	0
Total Amount of Unrecognized Tax Benefits at December	163	113	82
Accumulated Deferred Income Taxes Associated with Unrecognized Tax Benefits	(133)	(65)	(38)
Regulatory Asset-Unrecognized Tax Benefits	(30)	(20)	(16)
Amount of unrecognized tax benefits that would affect the effective tax rate	0	28	28
Energy Holdings [Member]
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Total Amount of Unrecognized Tax Benefits at January	555	539	820
Increases as a Result of Positions Taken in a Prior Period	9	17	90
Decreases as a Result of Positions Taken in a Prior Period	(119)	(12)	(383)
Increases as a Result of Positions Taken during the Current Period	0	11	12
Decreases as a Result of Positions Taken during the Current Period	0	0	0
Decreases as a Result of Settlements with Taxing Authorities	(344)	0	0
Decreases due to Lapses of Applicable Statute of Limitations	0	0	0
Total Amount of Unrecognized Tax Benefits at December	101	555	539
Accumulated Deferred Income Taxes Associated with Unrecognized Tax Benefits	(35)	(213)	(204)
Regulatory Asset-Unrecognized Tax Benefits	0	0	0
Amount of unrecognized tax benefits that would affect the effective tax rate	$ 66	$ 342	$ 335