Income Taxes (Textual) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended			9 Months Ended		12 Months Ended	3 Months Ended		9 Months Ended					3 Months Ended
	Sep. 30, 2014	Jun. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2015 Tax Years 2003 to 2006 IRS Examination Scenario, Forecast	Sep. 30, 2014 Southern California Edison	Sep. 30, 2013 Southern California Edison	Sep. 30, 2014 Southern California Edison	Sep. 30, 2013 Southern California Edison	Sep. 30, 2014 Southern California Edison Tax Years 2003 to 2006 IRS Examination Proposed Adjustment to Taxable Gain	Sep. 30, 2014 Southern California Edison Tax Years 2003 to 2006 IRS Examination Disallowance of Repair Allowance Deduction	Sep. 30, 2014 Southern California Edison Tax Years 2007 to 2009 IRS Examination Disallowance of Repair Allowance Deduction	Jun. 30, 2014 Southern California Edison Tax Years 2003 to 2010 IRS Examination Disallowance of Repair Allowance Deduction
Income Tax Disclosure [Line Items]
Reduction to revenue from repair deductions, before tax									$ 231
Estimated potential future federal tax payment as of the balance sheet date, including interest and penalties, based on a proposed adjustment											212	102	76
Deposit against IRS tax dispute adjustment		189
Estimated tax benefits						50						14	16
Income Tax Expense (Benefit)	$ (220)		$ (177)	$ (284)	$ (173)		$ (224)	$ (183)	$ (310)	$ (196)				$ 29