Pension And OPEB (Schedule Of Pension And OPEB Costs) (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Benefit Costs	$ (6)	$ 38
Pension Benefits [Member] | Power [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Benefit Costs	(2)	11
Pension Benefits [Member] | PSE And G [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Benefit Costs	(5)	23
Pension Benefits [Member] | Other Entity [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Benefit Costs	1	4
OPEB [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Benefit Costs	17	23
OPEB [Member] | Power [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Benefit Costs	5	6
OPEB [Member] | PSE And G [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Benefit Costs	11	16
OPEB [Member] | Other Entity [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Benefit Costs	$ 1	$ 1