Commitments And Contingent Liabilities (Regulatory Proceedings) (Details) (USD $) In Millions, unless otherwise specified	Sep. 30, 2011 mW	Mar. 31, 2011 mW
Loss Contingencies [Line Items]
New combined cycle generating facilities to be built under LCAPP		1,949
Mid-merit electric power generation capacity to be built under LCAPP	2,000
PSE&G [Member] | New Jersey Clean Energy Program Unfavorable Regulatory Action [Member]
Loss Contingencies [Line Items]
Aggregate funding for New Jersey Clean Energy Program	$ 705
Discounted liability recorded-total	294
Discounted liability recorded-current	224
Discounted liability recorded-noncurrent	70
New Jersey Clean Energy Program Unfavorable Regulatory Action [Member]
Loss Contingencies [Line Items]
Aggregate funding for New Jersey Clean Energy Program	$ 1,200