Commitments And Contingent Liabilities (New Generation And Development) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended													1 Months Ended			12 Months Ended
	Dec. 31, 2011 mW	Dec. 31, 2010	Dec. 31, 2009	Dec. 31, 2011 Power [Member]	Dec. 31, 2010 Power [Member]	Dec. 31, 2009 Power [Member]	Dec. 31, 2011 PSE&G [Member] mW	Dec. 31, 2010 PSE&G [Member]	Dec. 31, 2009 PSE&G [Member]	Dec. 31, 2011 Solar Capital Additions [Member] PSE&G [Member]	Dec. 31, 2011 PJM Interconnection Capital Additions [Member] Power [Member]	Dec. 31, 2011 Connecticut Capital Additions [Member] Power [Member] mW	Dec. 31, 2011 Nuclear Steam Path Capital Additions [Member] Power [Member] mW	Jan. 31, 2012 Energy Holdings-Solar [Member] mW	Sep. 30, 2011 Period 2012-2013 [Member] Kearny Site [Member] PJM Interconnection Capital Additions [Member] Power [Member] mW	Sep. 30, 2011 Period 2013-2015 [Member] PJM Interconnection Capital Additions [Member] Power [Member] mW	Dec. 31, 2011 Peach Bottom Units [Member] Nuclear Up Rate Capital Additions [Member] Power [Member] mW
Long-term Purchase Commitment [Line Items]
Approximate amount committed													$ 192				$ 400
Increase of MW nominal capacity after completion of upgrades													14				133
Total expenditures to date	2,083	2,160	1,794	757	825	869	1,302	1,257	855	185	203	129	114				36
Number of MW of gas fired peaking capacity to be built												130			178	267
Number of MW of solar generation on existing utility poles being installed							40
Number of MW of installation of solar generation on land and building							40
Approximately amount of MW's already installed	25						265,000,000
Guarantee payment of obligations														71.5
Estimated project costs														75
Estimated total cost of land and buildings owned phase	186
Number of MW of solar capacity placed into service	33
Long term purchase commitment amount low range											250	148
Approximate amount committed-high end of range											300
Investment in projects, amount										$ 160
Sites acquired during period														25
Solar units installed within service territory	200,000