Commitments And Contingent Liabilities (Regulatory Proceedings) (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended			3 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Mar. 31, 2014
Loss Contingencies [Line Items]
Costs recognized in Operation and Maintenance Expense	$ 3,150	$ 2,887	$ 2,632
Estimate of Total Costs required to restore damaged facilities	564
New Jersey Clean Energy Program [Member]
Loss Contingencies [Line Items]
Aggregate funding for New Jersey Clean Energy Program	345
Power [Member]
Loss Contingencies [Line Items]
Costs recognized in Operation and Maintenance Expense	1,186	1,224	1,127
Estimate of Total Costs required to restore damaged facilities	476
Power [Member] | Regulatory Agency [Domain]
Loss Contingencies [Line Items]
Loss Contingency, Loss in Period				25
Power [Member] | Superstorm Sandy [Member]
Loss Contingencies [Line Items]
Costs recognized in Operation and Maintenance Expense	27	79	85
Proceeds from insurance recoveries		25	19
PSE&G [Member]
Loss Contingencies [Line Items]
Costs recognized in Operation and Maintenance Expense	1,558	1,639	1,508
Estimate of Total Costs required to restore damaged facilities	88
PSE&G [Member] | New Jersey Clean Energy Program [Member]
Loss Contingencies [Line Items]
Aggregate funding for New Jersey Clean Energy Program	200
Discounted liability recorded-current	142
PSE&G [Member] | Superstorm Sandy [Member]
Loss Contingencies [Line Items]
Costs recognized in Operation and Maintenance Expense		40
Costs incurred to restore service		295
Cost recorded as Property, Plant and Equipment		75
Costs recorded as Regulatory Asset		180
Proceeds from insurance recoveries		$ 6