Permanent Retirement of San Onofre (Details) (USD $)			1 Months Ended			12 Months Ended		0 Months Ended	6 Months Ended	7 Months Ended	12 Months Ended			12 Months Ended		12 Months Ended	6 Months Ended				12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011 Southern California Edison	Dec. 31, 2013 Southern California Edison	Dec. 31, 2012 Southern California Edison	Dec. 31, 2013 San Onofre [Member]	Aug. 31, 2013 San Onofre [Member]	Jun. 06, 2013 San Onofre [Member] Southern California Edison	Jun. 30, 2013 San Onofre [Member] Southern California Edison positions	Dec. 31, 2013 San Onofre [Member] Southern California Edison invoices	Dec. 31, 2013 San Onofre [Member] Southern California Edison invoices	Aug. 31, 2013 San Onofre [Member] Southern California Edison	May 31, 2013 San Onofre [Member] Southern California Edison	Dec. 31, 2013 San Onofre [Member] Mitsubishi Heavy Industries Ltd [Member]	Dec. 31, 2013 Supporting Ongoing Activities at the Site [Member] San Onofre [Member] Southern California Edison	Dec. 31, 2013 Replacement Steam Generators [Member] San Onofre [Member] Southern California Edison	Jun. 30, 2013 Decommissioning Plan [Member] San Onofre [Member] Southern California Edison positions	Dec. 31, 2013 Building, plant and equipment [Member] San Onofre [Member] Southern California Edison	Dec. 31, 2013 Estimated Losses on Disposal of Nuclear Fuel Inventory [Member] San Onofre [Member] Southern California Edison	Dec. 31, 2013 Regulatory Balancing Accounts, Liabilities San Onofre [Member] Southern California Edison	Dec. 31, 2013 Employee Severance San Onofre [Member] Southern California Edison	Dec. 31, 2013 Indirect Employee Severance Costs [Member] San Onofre [Member] Southern California Edison
Regulatory Assets [Line Items]
Reduced power level of operation (as a percentage)														70.00%
Term of reduced power level of operation (in months)														5 months
Allowed Refueling Outage Costs Proposed Decision														$ 45,000,000
Disallowed Operation And Maintenance Costs Authorized in Rates														74,000,000
Percentage Of Revenue Requirement														20.00%
Cumulative Regulated Operating Revenue										1,250,000,000	1,250,000,000
Public Utilities Cost Of Service For Severance											39,000,000
Decommissioning Nuclear Facilities Net Investment													2,100,000,000
Authorized expenditures	525,000,000
Authorized expenditures, after adjustments for inflation										665,000,000	665,000,000
Ownership Interest										78.21%	78.21%
Authorized expenditures by authoritative body, spent to date											602,000,000
Authorized expenditures by authoritative body, market costs incurred								680,000,000		333,000,000
Authorized expenditures by authoritative body, Planned Outage Costs								65,000,000		30,000,000
Incremental inspection and repair costs											115,000,000
Incremental inspection and repair costs, payments from MHI											36,000,000
Reclassification To Regulatory Assets Amount													1,521,000,000
Regulatory assets	7,241,000,000	6,422,000,000		7,241,000,000	6,422,000,000										404,000,000
Asset impairment and other charges									575,000,000
Asset impairment net of tax									365,000,000
Restructuring and Related Cost, Expected Number of Positions Eliminated									960								175
Severance Costs																					39,000,000	14,000,000
Net Regulatory Assets										1,300,000,000	1,300,000,000							1,560,000,000	33,000,000	266,000,000
Steam generators, warranted period																20 years
MHI's limited liability under purchase agreement, excluding consequential damages														138,000,000
Notice of intent to sue, notice time period						90 days
Damages sought			98,000,000								4,000,000,000
Loss Contingency Counter Claim Amount														41,000,000
Number of invoices for reimbursement (in invoices)										7	7
Invoiced amount to MHI										149,000,000	149,000,000
Invoiced amount paid by MHI											45,000,000
Notice Of Claim Amount							$ 397,000,000					$ 311,000,000
Outage Policy Benefit Reduction Percentage						90.00%