Commitments and Contingencies (Details)			1 Months Ended	6 Months Ended		12 Months Ended
	May. 06, 2015 USD ($)	Apr. 17, 2015 USD ($)	Oct. 31, 2013 USD ($)	Jun. 30, 2015 USD ($) invoices site	Jun. 30, 2014 USD ($)	Dec. 31, 2012 USD ($)	Jun. 01, 2015 USD ($)	Aug. 31, 2014 USD ($)
Nuclear Insurance
Schedule Of Commitments And Contingencies [Line Items]
Federal limit on public liability claims from nuclear incident, approximate				$ 13,400,000,000
Nuclear Insurance | San Onofre
Schedule Of Commitments And Contingencies [Line Items]
San Bernardino settlement amount								$ 433,000,000
Southern California Edison
Schedule Of Commitments And Contingencies [Line Items]
Damages sought	$ 38,200,000	$ 648,000,000		$ 182,000,000
Identified material sites for environmental remediation (in number of sites) | site				19
Minimum costs to be Identified Site				$ 1,000,000
Minimum liability for environmental remediation for material sites				$ 115,000,000
Immaterial sites for environmental remediation (in number of sites) | site				39
Total minimum recorded liability for immaterial sites				$ 4,000,000
Environmental remediation liability				119,000,000
Regulatory assets related to environmental remediation				116,000,000
Portion of recorded liability recoverable from incentive mechanism				$ 30,000,000
Percentage of environmental remediation costs recoverable through an incentive mechanism (as a percent)				90.00%
Liability incurred at majority of the remaining sites through customer rates				$ 85,000,000
Environmental remediation costs to be recovered (as a percent)				100.00%
Amount that cleanup costs could exceed recorded liability for identified material sites				$ 159,000,000
Amount that cleanup costs could exceed recorded liability for immaterial sites				$ 8,000,000
Maximum expected period for cleanup of identified sites (in years)				30 years
Remediation cost estimates (period)				4 years
Expected annual environmental remediation costs, low end of range				$ 6,000,000
Expected annual environmental remediation costs, high end of range				24,000,000
Environmental remediation costs				3,000,000	$ 1,000,000
Insurance coverage for wildfire liabilities Limit				390,000,000			$ 610,000,000
Self insurance retention per wildfire occurrence							$ 10,000,000
Threshold for wildfire claims (new lines for additional coverage)				610,000,000
Southern California Edison | San Onofre
Schedule Of Commitments And Contingencies [Line Items]
Minimum liability for environmental remediation for material sites				$ 83,000,000
Southern California Edison | San Onofre | Mitsubishi Heavy Industries Ltd
Schedule Of Commitments And Contingencies [Line Items]
Damages sought			$ 4,000,000,000
Number of invoices for reimbursement | invoices				7
Invoiced amount for reimbursement				$ 149,000,000
Invoiced amount paid for reimbursement				$ 45,000,000
Share of invoice paid						$ 35,000,000
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				50.00%
Ratepayer allocation of recovery from recoveries, initial amount of settlement				$ 282,000,000
Southern California Edison | San Onofre | Replacement Steam Generators
Schedule Of Commitments And Contingencies [Line Items]
Warranty period				20 years
Southern California Edison | Other Insurance Claims | San Onofre
Schedule Of Commitments And Contingencies [Line Items]
Ratepayer allocation of recovery from recoveries				82.50%
Entity allocation of recovery from recoveries				17.50%
Southern California Edison | Nuclear Insurance
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
Southern California Edison | Nuclear Insurance | San Onofre
Schedule Of Commitments And Contingencies [Line Items]
Reduction in policy benefits following retirement of assets				90.00%
San Bernardino settlement amount								$ 339,000,000
Ratepayer allocation of recovery from recoveries				95.00%
Entity allocation of recovery from recoveries				5.00%
Mitsubishi Heavy Industries Ltd | San Onofre
Schedule Of Commitments And Contingencies [Line Items]
Maximum liability per purchase agreement for damages				$ 138,000,000
Asserted counterclaim			$ 41,000,000
SCE and other owners of San Onofre and Palo Verde | Nuclear Insurance | San Onofre and Palo Verde
Schedule Of Commitments And Contingencies [Line Items]
Loss limit, property damage insurance, federal minimum requirement				1,060,000,000
Power Purchase Contracts | Southern California Edison
Schedule Of Commitments And Contingencies [Line Items]
2015 additional commitments				41,000,000
2016 additional commitments				208,000,000
2017 additional commitments				297,000,000
2018 additional commitments				347,000,000
2019 additional commitments				384,000,000
Additional commitments due after 2019				$ 4,700,000,000