Summary of Significant Accounting Policies (Narrative) (Details) mi² in Thousands	1 Months Ended	3 Months Ended				12 Months Ended			24 Months Ended
	Dec. 31, 2014 USD ($)	Dec. 31, 2015 USD ($) MW	Dec. 31, 2014 USD ($)	Jun. 30, 2014 USD ($)	Jun. 30, 2013 USD ($)	Dec. 31, 2015 USD ($) mi² MW shares	Dec. 31, 2014 USD ($) financing shares	Dec. 31, 2013 USD ($) shares	Dec. 31, 2014 USD ($)	May. 31, 2013 USD ($)
Significant Accounting Policies [Line Items]
Reinvested Proceeds from Decommissioning Fund						$ 13,700,000,000	$ 7,500,000,000	$ 4,400,000,000
Maximum Maturity of Cash Equivalent Investments Period						3 months
Depreciation						$ 1,420,000,000	1,330,000,000	1,310,000,000
Impairment and other charges		$ 382,000,000				5,000,000	157,000,000	$ 571,000,000
Asset retirement obligations	$ 2,821,000,000	2,764,000,000	$ 2,821,000,000			2,764,000,000	2,821,000,000		$ 2,821,000,000
Regulatory assets	7,612,000,000	7,512,000,000	7,612,000,000			7,512,000,000	7,612,000,000		7,612,000,000
Assets	49,734,000,000	50,310,000,000	49,734,000,000			50,310,000,000	49,734,000,000		49,734,000,000
Liabilities	36,746,000,000	36,916,000,000	36,746,000,000			36,916,000,000	36,746,000,000		36,746,000,000
Net current deferred tax liabilities	(6,861,000,000)	(7,480,000,000)	(6,861,000,000)			$ (7,480,000,000)	$ (6,861,000,000)		(6,861,000,000)
Stock Compensation Plan
Significant Accounting Policies [Line Items]
Antidilutive stock option awards excluded from earnings per share, number of shares | shares						2,046,045	125,345	3,977,894
Southern California Edison
Significant Accounting Policies [Line Items]
Public Utilities Depreciation Expense Stated As A Percentage Of Average Original Cost Of Depreciable Utility Plant						3.90%	4.00%	4.20%
Estimated cost of debt and equity funds for construction, capitalized						$ 87,000,000	$ 65,000,000	$ 72,000,000
AFUDC debt capitalized during construction						31,000,000	25,000,000	33,000,000
Impairment and other charges						0	163,000,000	575,000,000
Asset retirement obligations	2,819,000,000	$ 2,762,000,000	2,819,000,000			2,762,000,000	2,819,000,000	3,418,000,000	2,819,000,000
Revisions to asset retirement obligation, increase (decrease)						$ (14,000,000)	(790,000,000)
Decommissioning Cost Escalated Rates, Low End of Range		1.40%				1.40%
Decommissioning Cost Escalated Rates, High End of Range		7.30%				7.30%
Decommissioning Funds Estimated Annual Earnings, Net of Tax Percentage, Low End of Range						3.30%
Decommissioning Funds Estimated Annual Earnings, Net of Tax Percentage, High End of Range						4.10%
Decommissioning Expense under Rate Making Method							5,000,000	22,000,000
Regulatory assets	7,612,000,000	$ 7,512,000,000	7,612,000,000			$ 7,512,000,000	7,612,000,000		7,612,000,000
Unamortized debt issuance expense	75,000,000	84,000,000	75,000,000			84,000,000	75,000,000		75,000,000
Franchise Fees Billed to Customers						$ 138,000,000	134,000,000	116,000,000
Period for calculation of weighted average common equity component (months)						13 months
Weighted Average Common Equity Component, Percentage of Total Capitalization						49.90%
Capacity to Pay Additional Dividends						$ 441,000,000
Restriction on net assets		13,200,000,000				13,200,000,000
Assets	49,456,000,000	49,872,000,000	49,456,000,000			49,872,000,000	49,456,000,000		49,456,000,000
Liabilities	36,174,000,000	36,200,000,000	36,174,000,000			36,200,000,000	36,174,000,000		36,174,000,000
Net current deferred tax liabilities	(8,497,000,000)	(9,073,000,000)	(8,497,000,000)			(9,073,000,000)	(8,497,000,000)		(8,497,000,000)
Southern California Edison | Loss on Reacquired Debt
Significant Accounting Policies [Line Items]
Regulatory assets	201,000,000	201,000,000	201,000,000			201,000,000	201,000,000		201,000,000
Southern California Edison | San Onofre 2 and 3
Significant Accounting Policies [Line Items]
Reclassification To Regulatory Assets Amount										$ 1,521,000,000
Impairment and other charges			68,000,000	$ 231,000,000	$ 575,000,000		163,000,000		738,000,000
Asset impairment net of tax			24,000,000	$ 96,000,000	$ 365,000,000		72,000,000		437,000,000
Revisions to asset retirement obligation, increase (decrease)							688,000,000
Southern California Edison | Palo Verde, San Onofre 1, 2 and 3 [Member]
Significant Accounting Policies [Line Items]
Decommissioning Active and Inactive Nuclear Facilities Asset Retirement Obligation		2,700,000,000				2,700,000,000
Decommissioning Estimated Cost						7,200,000,000
Southern California Edison | Palo Verde
Significant Accounting Policies [Line Items]
Increase (decrease) in asset retirement obligation	(253,000,000)
Southern California Edison | San Onofre 1
Significant Accounting Policies [Line Items]
Increase (decrease) in asset retirement obligation	124,000,000
Decommissioning Expenditures to Date		484,000,000				484,000,000
Southern California Edison | Other Current Assets
Significant Accounting Policies [Line Items]
Greenhouse Gas Allowances	204,000,000	79,000,000	204,000,000			79,000,000	204,000,000		204,000,000
Southern California Edison | Other Current Liabilities
Significant Accounting Policies [Line Items]
Greenhouse Gas Emission Obligations	211,000,000	86,000,000	211,000,000			86,000,000	211,000,000		211,000,000
Edison International
Significant Accounting Policies [Line Items]
Unamortized debt issuance expense	83,000,000	92,000,000	83,000,000			$ 92,000,000	83,000,000		83,000,000
Weighted Average Common Equity Component Minimum Percentage Authorization Set By C P U C						48.00%
Weighted-average common equity component authorization, set by CPUC remaining over number of months (in months)						13 months
Assets	$ 13,674,000,000	13,699,000,000	$ 13,674,000,000			$ 13,699,000,000	13,674,000,000		$ 13,674,000,000
Net income						1,020,000,000	$ 1,612,000,000	$ 915,000,000
Unidentified Subsidiary, Limited Liability Company
Significant Accounting Policies [Line Items]
Assets		82,000,000				82,000,000
Liabilities		$ 32,000,000				32,000,000
Net income						$ 16,000,000
Unidentified Subsidiary, Limited Liability Company | Call Option
Significant Accounting Policies [Line Items]
Term of derivative contract						9 months
Cooldown period after completion of project						5 years
Indirect Subsidiaries
Significant Accounting Policies [Line Items]
Number of new financings | financing							3
Power generating capacity for majority interest (in megawatts) | MW		29				29
Debt Instrument, Term						7 years
Percent of taxable profits and losses and tax credits attributable to tax equity investors, period one						99.00%
Period of taxable profits and losses and tax credits attributable to tax equity investors, period one						6 years
Priority return on investment for noncontrolling interest holders						2.00%
Percent of taxable profits and losses and tax credits attributable to tax equity investors, period two						5.00%
Electric Utility | Southern California Edison
Significant Accounting Policies [Line Items]
Supply Of Electricity Area Covered (in square miles) | mi²						50
Adjustments for New Accounting Principle, Early Adoption [Member]
Significant Accounting Policies [Line Items]
Net current deferred tax assets		$ 452,000,000				$ 452,000,000
Adjustments for New Accounting Principle, Early Adoption [Member] | Southern California Edison
Significant Accounting Policies [Line Items]
Net current deferred tax liabilities		$ 209,000,000				$ 209,000,000