Commitments and Contingencies (Undiscounted Future Minimum Expected Payments for Power Purchase Agreements) (Details) (Southern California Edison, USD $) In Millions, unless otherwise specified	Dec. 31, 2014
Renewable Energy Contracts
Power Purchase Agreements, Fiscal Year Maturity
2015	$ 1,009
2016	1,115
2017	1,162
2018	1,159
2019	1,214
Thereafter	17,740
Total future commitments	23,399
QF Power Purchase Agreements
Power Purchase Agreements, Fiscal Year Maturity
2015	254
2016	217
2017	191
2018	150
2019	88
Thereafter	69
Total future commitments	969
Other Purchase Agreements
Power Purchase Agreements, Fiscal Year Maturity
2015	830
2016	724
2017	729
2018	592
2019	496
Thereafter	1,504
Total future commitments	$ 4,875

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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

+ Details

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- Definition

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

+ Details

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- Definition

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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- Definition

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

+ Details

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- Definition

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

+ Details

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- Definition

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

+ Details

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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.

+ References

+ Details

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