Related-Party Transactions (Schedule Of Related Party Transactions, Payables) (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended	12 Months Ended
	Mar. 31, 2013	Dec. 31, 2012
PSE And G [Member]
Payable to Power through BGS and BGSS Contracts	$ (223)	$ (238)
Payable to Power Related to Gas Supply Hedges for BGSS	23	(27)
Payable to Power for SREC Liability	(7)	(7)
Receivable from (Payable to) Services	(52)	(65)
Tax Receivable from (Payable to) PSEG	160	256
Receivable from PSEG	7	6
Receivable from Energy Holdings	3	2
Accounts Payable-Affiliated Companies, net	(89)	(73)
Working Capital Advances to Services	33	33
Long-Term Accrued Taxes Payable	(39)	(32)
Accrued Liability for Excess SREC costs	17	17
Power's Share Of PSE&G's Liability [Member]
Accrued Liability for Excess SREC costs	$ 7	$ 7