Commitments and Contingencies (Contingencies Textual) (Details)	1 Months Ended					12 Months Ended
	Dec. 31, 2015 USD ($) sites invoices	Oct. 31, 2015 USD ($)	Aug. 31, 2015 communication	Oct. 31, 2013 USD ($)	Jun. 30, 2010 USD ($)	Dec. 31, 2015 USD ($) sites communication invoices	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)	Dec. 31, 2012 USD ($)	Jun. 01, 2015 USD ($)	Aug. 31, 2014 USD ($)	Aug. 30, 2014 USD ($)
Insurance Claims
Schedule Of Commitments And Contingencies [Line Items]
Federal Limit on Public Liability Claims from Nuclear Incident, Approximate						$ 13,500,000,000
San Onofre | Insurance Claims
Schedule Of Commitments And Contingencies [Line Items]
Loss Contingency, Estimate of Possible Loss												$ 433,000,000
Pre tax damages awarded to SCE		$ 400,000,000
Southern California Edison
Schedule Of Commitments And Contingencies [Line Items]
Loss Contingency, Damages Sought, Value					$ 112,000,000
Accrual for environmental loss contingencies (immaterial sites)	$ 3,000,000					$ 3,000,000
Number of Material Sites Identified for Environmental Remediation | sites	19					19
Minimum costs to be Identified Material Site						$ 1,000,000
Accrual for Environmental Loss Contingencies (material sites)	$ 131,000,000					$ 131,000,000
Number of Immaterial Sites for Environmental Remediation | sites						39
Accrued Environmental Loss Contingencies, Noncurrent	134,000,000					$ 134,000,000
Regulatory Assets, Noncurrent, Environmental Remediation	129,000,000					129,000,000
Portion of Recorded Liability Recoverable From Incentive Mechanism						$ 47,000,000
Percentage of Environmental Remediation Costs Recoverable From Incentive Mechanism						90.00%
Recorded Liability Incurred at Majority of Remaining Sites Through Customer Rates	82,000,000					$ 82,000,000
Percentage of Environmental Remediation Costs to be Recovered						100.00%
Amount that Cleanup Costs for Identified Material Sites Could Exceed Recorded Liability						$ 164,000,000
Amount that Cleanup Costs for Immaterial Sites Could Exceed Recorded Liability						$ 8,000,000
Maximum Expected Period for Clean Up of Identified Sites						30 years
Expected Annual Environmental Remediation Costs, Period for Cost Estimates						5 years
Expected Annual Environmental Remediation Costs, Low End of Range						$ 7,000,000
Expected Annual Environmental Remediation Costs, High End of Range						26,000,000
Environmental Remediation Expense						5,000,000	$ 4,000,000	$ 8,000,000
Insurance Coverage for Wildfire Liabilities Limit										$ 610,000,000
Increase In Self Insurance Retention Per Wildfire Occurrence										$ 10,000,000
Additional Coverage for Certain Wildfire Liabilities	390,000,000					390,000,000
Wildfire Threshold For Additional Coverage	610,000,000					610,000,000
Southern California Edison | Insurance Claims
Schedule Of Commitments And Contingencies [Line Items]
Maximum Deferred Insurance Premium Per Nuclear Incident						255,000,000
Maximum Yearly Assessment Per Nuclear Incident						38,000,000
Limit on Assessment of Retrospective Premium Adjustments, Per Year, Approximate						$ 45,000,000
Southern California Edison | San Onofre
Schedule Of Commitments And Contingencies [Line Items]
Number Of Communications That Should Have Been Reported | communication			9			8
Penalties	16,740,000
Accrual for Environmental Loss Contingencies (material sites)	80,000,000					$ 80,000,000
Southern California Edison | San Onofre | Mitsubishi Heavy Industries Ltd
Schedule Of Commitments And Contingencies [Line Items]
Ratepayer Allocation of Recovery from Recoveries						50.00%
Entity Allocation of Recovery from Recoveries (under accidental outage insurance)						50.00%
Ratepayer Allocation of Recovery from Recoveries, Initial Amount of Settlement						$ 282,000,000
Southern California Edison | San Onofre | Insurance Claims
Schedule Of Commitments And Contingencies [Line Items]
Loss Contingency, Estimate of Possible Loss											$ 339,000,000
Pre tax damages awarded to SCE		$ 313,000,000				$ 20,000,000
Ratepayer Allocation of Recovery from Recoveries						95.00%
Entity Allocation of Recovery from Recoveries (under accidental outage insurance)						5.00%
Southern California Edison | Replacement Steam Generators | San Onofre
Schedule Of Commitments And Contingencies [Line Items]
Warranty Period						20 years
SCE And Other Owners Of San Onofre And Palo Verde
Schedule Of Commitments And Contingencies [Line Items]
Loss Contingency, Damages Sought, Value					$ 142,000,000	$ 182,000,000
SCE And Other Owners Of San Onofre And Palo Verde | Insurance Claims
Schedule Of Commitments And Contingencies [Line Items]
Private Primary Insurance Purchased						375,000,000
SCE And Other Owners Of San Onofre And Palo Verde | Tort Claims For Onsite Workers
Schedule Of Commitments And Contingencies [Line Items]
Private Primary Insurance Purchased						375,000,000
SCE And Other Owners Of San Onofre And Palo Verde | San Onofre and Palo Verde | Insurance Claims
Schedule Of Commitments And Contingencies [Line Items]
Loss Limit, Property Damage Insurance, Federal Minimum Requirement						1,060,000,000
Mitsubishi Heavy Industries Ltd | San Onofre
Schedule Of Commitments And Contingencies [Line Items]
Maximum Liability Per Purchase Agreement for Damages	$ 138,000,000					$ 138,000,000
Loss Contingency Counter Claim Amount				$ 41,000,000
Mitsubishi Heavy Industries Ltd | Southern California Edison | San Onofre
Schedule Of Commitments And Contingencies [Line Items]
Loss Contingency, Damages Sought, Value				$ 4,000,000,000
Number of Invoices for Reimbursement | invoices	7					7
Gain Contingency, Invoiced Amount for Reimbursement	$ 149,000,000					$ 149,000,000
Gain Contingency, Invoiced Amount Paid for Reimbursement						$ 45,000,000
Public Utilities, Incremental Inspection and Repair Costs, Payments from Third Party									$ 35,000,000