Commitments And Contingent Liabilities (Regulatory Proceedings) (Detail) (USD $) In Millions, unless otherwise specified	1 Months Ended	3 Months Ended				12 Months Ended			3 Months Ended
	May 31, 2012	Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2013 PSE And G [Member] MW	Mar. 31, 2012 PSE And G [Member]	Dec. 31, 2012 PSE And G [Member] MW	May 31, 2012 PSE And G [Member] MW	Mar. 31, 2013 PSE And G [Member] New Jersey Clean Energy Program Unfavorable Regulatory Action [Member]	Mar. 31, 2013 Power [Member]	Mar. 31, 2012 Power [Member]	Mar. 31, 2013 Power [Member] Superstorm Sandy [Member]	Mar. 31, 2013 PSEG [Member] Superstorm Sandy [Member]
Loss Contingencies [Line Items]
Aggregate funding for New Jersey Clean Energy Program								$ 195
Discounted liability recorded-current								92
Aggregate notional amount of MW capacity				2,000			1,300
SOCA payments term	15 years
Percentage of Installed Capacity Under LCAPP Subsidiary Will Be Serving						52.00%
Number of Installed Capacity Under LCAPP Subsidiary Will Be Serving						676
Operation and Maintenance		710	628	427	376				282	241	28
Proceeds from Insurance Recoveries												$ 25