Property, Plant and Equipment (Textual) (Details) (Southern California Edison, USD $)	12 Months Ended			1 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2013
Property, Plant and Equipment [Line Items]
Capitalized software costs	$ 1,700,000,000	$ 1,600,000,000		$ 1,600,000,000
Capitalized software, accumulated amortization	1,000,000,000	839,000,000		839,000,000
Capitalized software, amortization expense	271,000,000	251,000,000	217,000,000
Capitalized software, estimated annual amortization expense for 2015 through 2019	275,000,000
Four Corners Unit 4 And 5 (coal)
Property, Plant and Equipment [Line Items]
Sale price of investment in facility				181,000,000
Benefit to ratepayer on sale of Four Corners				$ 166,000,000
Minimum | Capitalized Software Costs
Property, Plant and Equipment [Line Items]
Estimated Useful Lives	5 years
Maximum | Capitalized Software Costs
Property, Plant and Equipment [Line Items]
Estimated Useful Lives	15 years