Compensation and Benefit Plans (Textual) (Details) (USD $) In Millions, unless otherwise specified	6 Months Ended	3 Months Ended		6 Months Ended						3 Months Ended		6 Months Ended					6 Months Ended
	Jun. 30, 2013	Jun. 30, 2013 Pension Plans	Jun. 30, 2012 Pension Plans	Jun. 30, 2013 Pension Plans	Jun. 30, 2012 Pension Plans	Jun. 30, 2013 Postretirement Benefits Other Than Pensions	Jun. 30, 2013 Southern California Edison	May 31, 2013 Southern California Edison	Dec. 31, 2012 Southern California Edison	Jun. 30, 2013 Southern California Edison Pension Plans	Jun. 30, 2012 Southern California Edison Pension Plans	Jun. 30, 2013 Southern California Edison Pension Plans	Jun. 30, 2012 Southern California Edison Pension Plans	Jun. 30, 2013 Southern California Edison Postretirement Benefits Other Than Pensions	May 31, 2013 Initial	May 31, 2013 Revised	Jun. 30, 2013 San Onofre [Member] Southern California Edison positions	Jun. 30, 2013 Decommissioning Plan San Onofre [Member] Southern California Edison positions
Pension and Other Postretirement Benefits
San Onofre expected number of positions to be eliminated																	960	175
Defined Benefit Plan, Actuarial Gain (Loss)	$ 369						$ 362
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate															3.75%	4.25%
Settlement costs		49	0	49	0					48	0	48	0
Defined Benefit Plan, Unfunded Status of Plan								658	1,100
Employer contributions				104		15						94		15
Estimated future contributions in remainder of 2013		$ 86		$ 86		$ 20				$ 70		$ 70		$ 20