Other Investments (Summary of Changes in Fair Value of the Nuclear Decommissioning Trusts) (Details) (USD $) In Millions, unless otherwise specified			3 Months Ended
Mar. 31, 2014	Dec. 31, 2013	Mar. 31, 2014 Southern California Edison	Mar. 31, 2013 Southern California Edison
Summary Of Changes In The Fair Value [Roll Forward]
Balance at beginning of period	$ 4,587	$ 4,494	$ 4,494	$ 4,048
Gross realized gains			10	5
Gross realized losses			0	(1)
Unrealized gains, net			62	176
Other-than-temporary impairments			(3)	(8)
Interest, dividends, contributions and other			24	26
Balance at end of period	$ 4,587	$ 4,494	$ 4,587	$ 4,246

Discloses the amount of interest, dividend, contribution and other receipts during the period.

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Discloses the amount of other than temporary decline in value that has been recognized by the decommissioning trust during the period.

+ References

No definition available.

+ Details

Name:	eix_DecommissioningTrustOtherThanTemporaryImpairments
Namespace Prefix:	eix_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

This item represents the amount of realized gain on investments in trust during the period from the sale of securities.

+ References

No definition available.

+ Details

Name:	eix_DecommissioningTrustRealizedGainOnInvestments
Namespace Prefix:	eix_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

This item represents the amount of realized loss on investments in trust during the period from the sale of securities.

+ References

No definition available.

+ Details

Name:	eix_DecommissioningTrustRealizedLossOnInvestments
Namespace Prefix:	eix_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

This item represents the amount of net unrealized gain on investments in trust during the period.

+ References

No definition available.

+ Details

Name:	eix_DecommissioningTrustUnrealizedGainsOnInvestmentsNet
Namespace Prefix:	eix_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

Name:	eix_SummaryOfChangesInFairValueRollForward
Namespace Prefix:	eix_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The fair value of investments held in a trust fund to pay for the costs of decontaminating and decommissioning facilities, whether such amount is presented as a separate caption or as a parenthetical disclosure on the balance sheet. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 410

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant