Commitments and Contingencies (Nuclear Insurance) (Details) - Nuclear Insurance	9 Months Ended
Sep. 30, 2017 USD ($)
Schedule Of Commitments And Contingencies [Line Items]
Federal limit on public liability claims from nuclear incident, approximate	$ 13,400,000,000
SCE and other owners of San Onofre and Palo Verde \| San Onofre and Palo Verde
Schedule Of Commitments And Contingencies [Line Items]
Loss limit, property damage insurance, federal minimum requirement	1,060,000,000
Southern California Edison
Schedule Of Commitments And Contingencies [Line Items]
Limit on assessment of retrospective premium adjustments, per year, approximate	52,000,000
Maximum assessment per each nuclear incident	255,000,000
Maximum yearly assessment per nuclear incident	$ 38,000,000

The approximate maximum amount of public liability, as limited by federal law, resulting from a nuclear incident.

No definition available.

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The approximate maximum yearly retrospective premium adjustments that could be assessed against the entity.

No definition available.

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Loss Limit, Property Damage Insurance, Federal Minimum Requirement

No definition available.

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The maximum amount of deferred insurance premium based on each nuclear incident occurring.

No definition available.

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The maximum amount of additional insurance premium per yearly assessment charged for each nuclear incident.

No definition available.

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Schedule Of Commitments And Contingencies [Line Items]

No definition available.

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