Regulatory Assets and Liabilities (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013
Regulatory Assets
Regulatory Assets, Current	$ 931	$ 538
Regulatory Asset, Long-term	7,351	7,241
Regulatory Liabilities
Regulatory Liabilities, Current	455	767
Regulatory Liabilities, Long-term	5,655	4,995
Southern California Edison
Regulatory Assets
Regulatory Assets, Current	931	538
Regulatory Asset, Long-term	7,351	7,241
Total Regulatory Assets	8,282	7,779
Regulatory Liabilities
Regulatory Liabilities, Current	455	767
Regulatory Liabilities, Long-term	5,655	4,995
Total Regulatory Liabilities	6,110	5,762
Southern California Edison \| Regulatory balancing accounts
Regulatory Assets
Regulatory Assets, Current	883	484
Regulatory Asset, Long-term	819	818
Southern California Edison \| Energy derivatives
Regulatory Assets
Regulatory Assets, Current	48	54
Regulatory Asset, Long-term	768	816
Southern California Edison \| Deferred income taxes, net
Regulatory Assets
Regulatory Asset, Long-term	3,116	2,957
Southern California Edison \| Other
Regulatory Assets
Regulatory Asset, Long-term	339	368
Regulatory Liabilities
Regulatory Liabilities, Current	38	43
Regulatory Liabilities, Long-term	14	12
Southern California Edison \| Pensions and other postretirement benefits
Regulatory Assets
Regulatory Asset, Long-term	377	369
Southern California Edison \| Unamortized investments, net
Regulatory Assets
Regulatory Asset, Long-term	312	332
Southern California Edison \| San Onofre (nuclear)
Regulatory Assets
Regulatory Asset, Long-term	1,371	1,325
Southern California Edison \| Unamortized loss on reacquired debt
Regulatory Assets
Regulatory Asset, Long-term	216	222
Southern California Edison \| Nuclear-related investment, net
Regulatory Assets
Regulatory Asset, Long-term	33	34
Southern California Edison \| Regulatory balancing accounts
Regulatory Liabilities
Regulatory Liabilities, Current	417	724
Regulatory Liabilities, Long-term	1,347	1,132
Southern California Edison \| Costs of Removal
Regulatory Liabilities
Regulatory Liabilities, Long-term	2,811	2,780
Southern California Edison \| Asset Retirement Obligations
Regulatory Liabilities
Regulatory Liabilities, Long-term	$ 1,112	$ 1,071

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- Definition

The amount for the individual regulatory asset as itemized in a table of regulatory assets as of the end of the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 980

-SubTopic 340

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6499975&loc=d3e44250-110382

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- Definition

Carrying amount as of the balance sheet date of capitalized costs of regulated entities that are expected to be recovered through revenue sources within one year or the normal operating cycle, if longer. Such costs are capitalized if they meet both of the following criteria: a. It is probable that future revenue in an amount at least equal to the capitalized cost will result from inclusion of that cost in allowable costs for rate-making purposes. b. Based on available evidence, the future revenue will be provided to permit recovery of the previously incurred cost rather than to provide for expected levels of similar future costs. If the revenue will be provided through an automatic rate-adjustment clause, this criterion requires that the regulator's intent clearly be to permit recovery of the previously incurred cost.

+ References

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- Definition

Carrying amount as of the balance sheet date of capitalized costs of regulated entities that are not expected to be recovered through revenue sources within one year or the normal operating cycle if longer.

+ References

+ Details

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- Definition

The amount for the individual regulatory liability as itemized in a table of regulatory liabilities as of the end of the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 980

-SubTopic 405

-Section 25

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6500807&loc=d3e48068-110394

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- Definition

The amount for the individual regulatory current liability as itemized in a table of regulatory current liabilities as of the end of the period.

+ References

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- Definition

The amount for the individual regulatory noncurrent liability as itemized in a table of regulatory noncurrent liabilities as of the end of the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.24)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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