Income Taxes (Tax Rate Reconciliation) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Effective Tax Rate
Income from continuing operations before income taxes	$ 424	$ 205
Provision for income tax at federal statutory rate of 35%	148	71
State tax, net of federal benefit	11	1
Property-related	(60)	(51)
Change related to uncertain tax positions	15	7
San Onofre OII settlement	0	(40)
Other	(8)	(7)
Total income tax expense (benefit) from continuing operations	106us-gaap_IncomeTaxExpenseBenefit	(19)us-gaap_IncomeTaxExpenseBenefit
Effective tax rate	25.00%	(9.30%)
Federal statutory rate	35.00%	35.00%
Southern California Edison
Effective Tax Rate
Income from continuing operations before income taxes	440	222
Provision for income tax at federal statutory rate of 35%	154	78
State tax, net of federal benefit	14	1
Property-related	(60)	(51)
Change related to uncertain tax positions	10	7
San Onofre OII settlement	0	(40)
Other	(11)	(7)
Total income tax expense (benefit) from continuing operations	$ 107	$ (12)
Effective tax rate	24.30%	(5.40%)
Federal statutory rate	35.00%	35.00%

Effective Tax Rate Excluding Income Attributable to Noncontrolling Interests

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Sum of operating profit and nonoperating income or expense before income taxes and noncontrolling interest.

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Income Tax Reconciliation Adjustment Tax Reserve Adjustment

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The portion of the difference between the total income tax expense (benefit) as reported in the Income Statement for the year/accounting period and the expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates.

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Income Tax Reconciliation Settlement Amount

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from continuing operations.

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to other adjustments.

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