Accumulated Other Comprehensive Income (Loss), Net of Tax (Changes of AOCI) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended								3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2012 Derivative Contracts [Member]	Dec. 31, 2011 Derivative Contracts [Member]	Mar. 31, 2012 Pension and OPEB Plans [Member]	Dec. 31, 2011 Pension and OPEB Plans [Member]	Mar. 31, 2012 Available-for-Sale Securities [Member]	Dec. 31, 2011 Available-for-Sale Securities [Member]	Mar. 31, 2013 PSEG [Member]	Mar. 31, 2013 PSEG [Member] Derivative Contracts [Member]	Mar. 31, 2013 PSEG [Member] Pension and OPEB Plans [Member]	Mar. 31, 2013 PSEG [Member] Available-for-Sale Securities [Member]	Mar. 31, 2013 Power [Member]	Mar. 31, 2012 Power [Member]	Mar. 31, 2013 Power [Member] Derivative Contracts [Member]	Mar. 31, 2012 Power [Member] Derivative Contracts [Member]	Mar. 31, 2013 Power [Member] Pension and OPEB Plans [Member]	Mar. 31, 2012 Power [Member] Pension and OPEB Plans [Member]	Mar. 31, 2013 Power [Member] Available-for-Sale Securities [Member]	Mar. 31, 2012 Power [Member] Available-for-Sale Securities [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Accumulated Other Comprehensive Income (Loss), Beginning Balance	$ (388)	$ (337)	$ 31	$ 31	$ (431)	$ (438)	$ 107	$ 70	$ (388)	$ 7	$ (485)	$ 90	$ (328)		$ 9		$ (422)		$ 85
Other Comprehensive Income before Reclassifications									27	0	0	27	27		0		0		27
Amounts Reclassified from Accumulated Other Comprehensive Income (Loss)									6	(4)	10	0	5		(4)		9		0
Other Comprehensive Income (Loss), net of tax	33	44							33	(4)	10	27	32	44	(4)	0	9	7	27	37
Accumulated Other Comprehensive Income (Loss), Ending Balance	$ (355)	$ (293)	$ 31	$ 31	$ (431)	$ (438)	$ 107	$ 70	$ (355)	$ 3	$ (475)	$ 117	$ (296)		$ 5		$ (413)		$ 112