Accumulated Other Comprehensive Income (Loss), Net Of Tax (Schedule Of AOCI) (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended							3 Months Ended			3 Months Ended						3 Months Ended						3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2013 Power [Member]	Mar. 31, 2012 Power [Member]	Mar. 31, 2012 PSE And G [Member]	Mar. 31, 2013 PSE And G [Member]	Dec. 31, 2012 PSE And G [Member]	Mar. 31, 2012 Other [Member]	Mar. 31, 2012 Derivative Contracts [Member]	Dec. 31, 2011 Derivative Contracts [Member]	Mar. 31, 2013 Derivative Contracts [Member] Power [Member]	Mar. 31, 2012 Derivative Contracts [Member] Power [Member]	Mar. 31, 2012 Derivative Contracts [Member] PSE And G [Member]	Mar. 31, 2012 Derivative Contracts [Member] Other [Member]	Mar. 31, 2012 Pension and OPEB Plans [Member]	Dec. 31, 2011 Pension and OPEB Plans [Member]	Mar. 31, 2013 Pension and OPEB Plans [Member] Power [Member]	Mar. 31, 2012 Pension and OPEB Plans [Member] Power [Member]	Mar. 31, 2012 Pension and OPEB Plans [Member] PSE And G [Member]	Mar. 31, 2012 Pension and OPEB Plans [Member] Other [Member]	Mar. 31, 2012 Available-for-Sale Securities [Member]	Dec. 31, 2011 Available-for-Sale Securities [Member]	Mar. 31, 2013 Available-for-Sale Securities [Member] Power [Member]	Mar. 31, 2012 Available-for-Sale Securities [Member] Power [Member]	Mar. 31, 2012 Available-for-Sale Securities [Member] PSE And G [Member]	Mar. 31, 2012 Available-for-Sale Securities [Member] Other [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated Other Comprehensive Income (Loss), Beginning Balance	$ (388)	$ (337)	$ (328)			$ 2	$ 2		$ 31	$ 31	$ 9				$ (431)	$ (438)	$ (422)				$ 107	$ 70	$ 85
Other Comprehensive Income (Loss), Net of Tax	33	44	32	44	(1)			1			(4)	0	0	0			9	7	0	0			27	37	(1)	1
Accumulated Other Comprehensive Income (Loss), Ending Balance	$ (355)	$ (293)	$ (296)			$ 2	$ 2		$ 31	$ 31	$ 5				$ (431)	$ (438)	$ (413)				$ 107	$ 70	$ 112