Summary of Significant Accounting Policies (Deferred Financing Costs) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Regulatory assets	$ 7,241	$ 6,422
Southern California Edison
Regulatory assets	7,241	6,422
Unamortized debt issuance expense	79	67
Amortization of deferred financing costs	46	29	33
Southern California Edison | Loss on Reacquired Debt
Regulatory assets	222	228
Edison International
Unamortized debt issuance expense	84	73
Amortization of deferred financing costs	$ 47	$ 30	$ 34