San Onofre Issues (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended				0 Months Ended	3 Months Ended	6 Months Ended			12 Months Ended					3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2014 Southern California Edison	Mar. 31, 2013 Southern California Edison	Jun. 06, 2013 Southern California Edison San Onofre (nuclear)	Mar. 31, 2014 Southern California Edison San Onofre (nuclear)	Jun. 30, 2013 Southern California Edison San Onofre (nuclear)	Dec. 31, 2013 Southern California Edison San Onofre (nuclear)	May 31, 2013 Southern California Edison San Onofre (nuclear)	Dec. 31, 2012 Southern California Edison San Onofre (nuclear) Replacement Steam Generators	Feb. 01, 2012 Southern California Edison San Onofre (nuclear) Replacement Steam Generators	Dec. 31, 2013 Southern California Edison San Onofre (nuclear) Property, plant and equipment	Mar. 31, 2014 Southern California Edison San Onofre (nuclear) Refunds of excess revenue	Dec. 31, 2013 Southern California Edison San Onofre (nuclear) Refunds of excess revenue	Mar. 31, 2014 Southern California Edison San Onofre (nuclear) 2012 Period	Mar. 31, 2014 Southern California Edison San Onofre (nuclear) 2013-2014 Periods	May 31, 2013 Southern California Edison San Onofre (nuclear) Disallowance Of SGRP Investment [Member]	Mar. 31, 2014 Southern California Edison San Onofre (nuclear) Refund of SGRP Revenue Previously Recognized [Member]	Mar. 31, 2014 Southern California Edison San Onofre (nuclear) Refund Of Flow Through Tax Benefits [Member]
Regulatory Assets [Line Items]
Settlement Agreement Subject Termination Period						6 months
Decommissioning Nuclear Facilities Net Investment											$ 597
Incremental Inspection and Repair Costs										99
Period For Rate Recovery						10 years
Authorized expenditures by authoritative body, market costs incurred					680
Authorized Return on Preferred Equity Percentage						50.00%
Public Utilities, Approved Return on Equity, Percentage															2.95%	2.62%
Amount of assets reclassified to a regulatory asset									1,521
Impairment and other charges	231	0	231	0		231	575
Impairment and other charges net of tax						96	365
Cumulative Impact of Settlement						806											542	159	71
Cumulative Impact of Settlement, Net of Tax						461
Net regulatory asset						$ 1,370		$ 1,300				$ 1,560	$ 371	$ 266