Commitments And Contingent Liabilities (Environmental Matters) (Details) (USD $)	9 Months Ended										3 Months Ended											12 Months Ended			12 Months Ended
	Sep. 30, 2011 gal	Dec. 31, 2011	Dec. 31, 2010	Apr. 30, 2009 mW	Dec. 15, 2007	Dec. 31, 2011 Power [Member]	Dec. 31, 2011 PSE&G [Member]	Dec. 31, 2010 PSE&G [Member]	Dec. 31, 2010 NJ Industrial Site Recovery Act Site Contingency [Member]	Dec. 31, 2011 PSD NSR Regulations Site Contingency [Member] Power [Member]	Jun. 30, 2008 Passaic River Site Contingency [Member]	Dec. 31, 2011 Passaic River Site Contingency [Member]	Dec. 31, 2007 Passaic River Site Contingency [Member]	Dec. 31, 2003 Passaic River Site Contingency [Member]	Sep. 30, 2011 Passaic River Site Contingency [Member] PSE&G [Member]	Feb. 28, 2009 Passaic River Site Contingency [Member] Power [Member] PSE&G [Member]	Sep. 30, 2011 Passaic River Site Contingency [Member] Transferred To Power From PSE&G [Member]	Dec. 31, 2011 MGP Remediation Site Contingency [Member] PSE&G [Member]	Dec. 31, 2011 MGP Remediation Site Contingency [Member] PSE&G [Member]	Sep. 30, 2011 MGP Remediation Site Contingency [Member] PSE&G [Member]	Dec. 31, 2011 PSE&G's Former MGP Sites [Member]	Dec. 31, 2011 PSE&G's Former MGP Sites [Member] PSE&G [Member]	Dec. 31, 2006 PSE&G's Former MGP Sites [Member] PSE&G [Member]	Dec. 31, 2006 PSE&G's Former MGP Sites [Member] Power [Member]	Dec. 31, 2011 Maximum [Member] Remedial Investigation And Feasibility Study [Member]	Dec. 31, 2011 Minimum [Member] 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
Original estimated cost of feasibility study																							$ 20,000,000
Estimated, total cost of the study																						99,000,000			150,000,000	20,000,000
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																						71
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
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																				635,000,000
Estimated expenditures, high end of range																				733,000,000
Accrued environmental costs		643,000,000	669,000,000				592,000,000	617,000,000	50,000,000											635,000,000
Remediation liability recorded as other current liabilities																			53,000,000
Remediation liability recorded as environmental costs in noncurrent liabilities																			582,000,000
Regulatory assets							4,897,000,000	5,019,000,000										635,000,000
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%
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
Total production capacity	2,000,000
New Salem facility cooling towers estimated cost total		$ 1,000,000,000				$ 575,000,000