Summary of Significant Accounting Policies (Property, Plant and Equipment) (Details) (USD $)	12 Months Ended			3 Months Ended		12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Jun. 30, 2013 San Onofre [Member]	Dec. 31, 2013 San Onofre [Member]	Dec. 31, 2013 Southern California Edison	Dec. 31, 2012 Southern California Edison	Dec. 31, 2011 Southern California Edison	Dec. 31, 2013 Southern California Edison Generation plant	Dec. 31, 2013 Southern California Edison Distribution plant	Dec. 31, 2013 Southern California Edison Transmission plant	Dec. 31, 2013 Southern California Edison General plant and other	Dec. 31, 2013 Southern California Edison Minimum Generation plant	Dec. 31, 2013 Southern California Edison Minimum Distribution plant	Dec. 31, 2013 Southern California Edison Minimum Transmission plant	Dec. 31, 2013 Southern California Edison Minimum General plant and other	Dec. 31, 2013 Southern California Edison Maximum Generation plant	Dec. 31, 2013 Southern California Edison Maximum Distribution plant	Dec. 31, 2013 Southern California Edison Maximum Transmission plant	Dec. 31, 2013 Southern California Edison Maximum General plant and other
Property, Plant and Equipment [Line Items]
Estimated Useful Lives													12 years	20 years	40 years	5 years	60 years	60 years	65 years	60 years
Weighted-Average Useful Lives									38 years	40 years	46 years	23 years
Depreciation expense of utility property, plant and equipment	$ 1,310,000,000	$ 1,260,000,000	$ 1,160,000,000
Depreciation expense stated as a percent of average original cost of depreciable utility plant (percent)						4.20%	4.30%	4.30%
Allowance for funds used during construction equity						72,000,000	96,000,000	96,000,000
Allowance for funds used during construction debt						33,000,000	40,000,000	42,000,000
Asset Retirement Obligation, Roll Forward
Beginning balance	2,782,000,000				2,680,000,000	2,782,000,000	2,610,000,000
Accretion						182,000,000	161,000,000
Revisions				455,000,000		455,000,000	12,000,000
Liabilities settled						(1,000,000)	(1,000,000)
Ending balance	$ 3,418,000,000	$ 2,782,000,000			$ 2,680,000,000	$ 3,418,000,000	$ 2,782,000,000	$ 2,610,000,000