Commitments and Contingencies (Undiscounted Future Minimum Expected Payments for Power Purchase Agreements) (Details) (Southern California Edison, USD $) In Millions, unless otherwise specified	Dec. 31, 2012
Renewable Energy Contracts
Power Purchase Agreements, Fiscal Year Maturity
2013	$ 629
2014	685
2015	756
2016	780
2017	781
Thereafter	13,031
Total future commitments	16,662
QF Power Purchase Agreements
Power Purchase Agreements, Fiscal Year Maturity
2013	361
2014	358
2015	324
2016	258
2017	226
Thereafter	387
Total future commitments	1,914
Other Purchase Agreements
Power Purchase Agreements, Fiscal Year Maturity
2013	851
2014	891
2015	765
2016	531
2017	523
Thereafter	2,554
Total future commitments	$ 6,115

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Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the fifth fiscal year following the latest fiscal year.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 440

-SubTopic 10

-Section 50

-Paragraph 4

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6394976&loc=d3e25336-109308

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 47

-Paragraph 7

-Subparagraph b

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the next fiscal year following the latest fiscal year.

+ References

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Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the four fiscal year following the latest fiscal year.

+ References

+ Details

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Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the second fiscal year following the latest fiscal year.

+ References

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Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the third fiscal year following the latest fiscal year.

+ References

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Amount of the unrecorded obligation to transfer funds in the future for fixed or minimum amounts or quantities of goods or services at fixed or minimum prices (for example, as in take-or-pay contracts or throughput contracts).

+ References

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- Definition

Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing after the fifth fiscal year following the latest fiscal year.

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