Commitments And Contingent Liabilities (Environmental Matters) (Detail) (USD $)	1 Months Ended	6 Months Ended								1 Months Ended										6 Months Ended					6 Months Ended
	Apr. 30, 2011 gal	Jun. 30, 2012 mi	Dec. 31, 2011	Jul. 31, 2011	Apr. 30, 2009 Turbines MW	Dec. 15, 2007	Jun. 30, 2012 PSE And G [Member]	Dec. 31, 2011 PSE And G [Member]	Jun. 30, 2012 Power [Member]	Dec. 31, 2011 PSEG [Member]	Jun. 30, 2008 Passaic River Site Contingency [Member]	Jun. 30, 2012 Passaic River Site Contingency [Member]	Dec. 31, 2007 Passaic River Site Contingency [Member] mi	Dec. 31, 2003 Passaic River Site Contingency [Member]	Jun. 30, 2012 Passaic River Site Contingency [Member] Transferred To Power From PSE&G [Member]	Jun. 30, 2012 Passaic River Site Contingency [Member] PSE And G [Member]	Feb. 28, 2009 Passaic River Site Contingency [Member] PSE And G [Member] Segment	Feb. 28, 2009 Passaic River Site Contingency [Member] Power [Member]	Jun. 30, 2012 PSE&G's Former MGP Sites [Member]	Jun. 30, 2012 PSE&G's Former MGP Sites [Member] PSE And G [Member] Person	Dec. 31, 2006 PSE&G's Former MGP Sites [Member] PSE And G [Member]	Dec. 31, 2006 PSE&G's Former MGP Sites [Member] Power [Member]	Jun. 30, 2012 PSD NSR Regulations Site Contingency [Member] Power [Member]	Jun. 30, 2012 MGP Remediation Site Contingency [Member] PSE And G [Member]	Jun. 30, 2012 Remedial Investigation And Feasibility Study [Member]
Site Contingency [Line Items]
Number of miles related to the Passaic River constituting a facility as determined by the US Environmental Protection Agency		8
Number of miles on Passaic River tidal reach required to be studied as determined by the US Environmental Protection Agency		17
Number of operating electric generating station (Essex Site)															1
Number of former generating electric station																1
Number of former Manufactured Gas Plant (MGP) sites																4	11
Original estimated cost of feasibility study																					$ 20,000,000
Estimated, total cost of the study																				105,000,000					30,000,000
Number of potentially responsible parties ("PRPs") in connection with environmental liabilities for operations conducted near Passaic River																				73
Number of current potentially responsible parties ("PRPs") in connection with environmental liabilities for operations conducted near Passaic River																				70
Percentage of cost attributable to potentially responsible party																					5.00%	1.00%
Number of miles of Passaic River which EPA released a draft (Focused Feasibility Study) that proposes six options to address the contamination cleanup													8
Estimated cleanup costs-low estimate												1,300,000,000
Estimated cleanup costs-high estimate												3,700,000,000
Estimated cleanup costs agreed to by two potentially responsible parties											80,000,000
PSEG's share of Pilot study																									3.00%
Aggregate number of defendants including registrant entities Power and PSE&G included in NJDEP complaint filed February 2009																		320
Aggregate number of PRPs directed by the NJDEP to arrange for natural resource damage assessment and interim compensatory restoration along the lower Passaic River														56
Estimated cost of interim natural resource injury restoration												950,000,000
Number of legal entities contacted by EPA in conjunction with Newark Bay study area contamination		11
Number of operating electric generating stations located on Hackensack River		2
Number of former MGP contamination sites located on Hackensack river in conjunction with Newark Bay study area contamination		1
Number of MGP sites identified by registrant and the NJDEP requiring some level of remedial action																			38
Estimated expenditures, low end of range																								616,000,000
Estimated expenditures, high end of range																								714,000,000
Accrued environmental costs		588,000,000	643,000,000				537,000,000	592,000,000																616,000,000
Remediation liability recorded as other current liabilities																								90,000,000
Remediation liability recorded as environmental costs in noncurrent liabilities																								526,000,000
Regulatory assets																								616,000,000
Penalty per day from date of violation-minimum																							25,000
Penalty per day from date of violation-maximum																							37,500
Ownership percentage of Keystone Coal fired plant in Pennsylvania									23.00%
Estimated cost of additional control		5,000,000
Parent companies share of investment in Clean Air Act requirements										147,000,000
Percentage of reduction required by New Jersey regulations on coal fired electric generating units						90.00%
Number of combustion turbines required to be retired to meet NOx emission reduction requirements					102
Number of MW required to be retired to meet NOx emission reduction requirements					2,000
Number of steam electric generation units requiring significant capital investment for additional controls or retirement as determined by NJDEP					4
Number of MW requiring significant capital investment for additional controls or retirement as determined by NJDEP					400
Number of states with limits on emissions under CSAPR				28
Total production capacity	2,000,000
New Salem facility cooling towers estimated cost total		$ 1,000,000,000							$ 575,000,000