Compensation and Benefit Plans (Expected Future Benefit Payments) (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2012
Pension Plans
Defined Benefit Plan, Expected Future Benefit Payments, Fiscal Year Maturity [Abstract]
Expected Future Benefit Payments - 2013	$ 327
Expected Future Benefit Payments - 2014	322
Expected Future Benefit Payments - 2015	372
Expected Future Benefit Payments - 2016	349
Expected Future Benefit Payments - 2017	350
Expected Future Benefit Payments - 2018 - 2022	1,736
Postretirement Benefits Other Than Pensions
Defined Benefit Plan, Estimated Future Benefit Payments, Gross [Abstract]
Expected Future Benefit Payments - 2013	91
Expected Future Benefit Payments - 2014	97
Expected Future Benefit Payments - 2015	103
Expected Future Benefit Payments - 2016	109
Expected Future Benefit Payments - 2017	116
Expected Future Benefit Payments - 2018 - 2022	662
Southern California Edison \| Pension Plans
Defined Benefit Plan, Expected Future Benefit Payments, Fiscal Year Maturity [Abstract]
Expected Future Benefit Payments - 2013	295
Expected Future Benefit Payments - 2014	295
Expected Future Benefit Payments - 2015	303
Expected Future Benefit Payments - 2016	310
Expected Future Benefit Payments - 2017	311
Expected Future Benefit Payments - 2018 - 2022	1,568
Southern California Edison \| Postretirement Benefits Other Than Pensions
Defined Benefit Plan, Expected Future Benefit Payments, Fiscal Year Maturity [Abstract]
Expected Future Benefit Payments - 2013	90
Expected Future Benefit Payments - 2014	97
Expected Future Benefit Payments - 2015	103
Expected Future Benefit Payments - 2016	109
Expected Future Benefit Payments - 2017	116
Expected Future Benefit Payments - 2018 - 2022	$ 659

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The gross amount of benefits, which do not include prescription drug subsidy receipts, expected to be paid in five fiscal years thereafter.

+ References

No definition available.

+ Details

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- Definition

The gross amount of benefits, which do not include prescription drug subsidy receipts, expected to be paid in year five.

+ References

No definition available.

+ Details

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- Definition

The gross amount of benefits, which do not include prescription drug subsidy receipts, expected to be paid in year four.

+ References

No definition available.

+ Details

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- Definition

The gross amount of benefits, which do not include prescription drug subsidy receipts, expected to be paid in year one.

+ References

No definition available.

+ Details

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- Definition

The gross amount of benefits, which do not include prescription drug subsidy receipts, expected to be paid in year three.

+ References

No definition available.

+ Details

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- Definition

The gross amount of benefits, which do not include prescription drug subsidy receipts, expected to be paid in year two.

+ References

No definition available.

+ Details

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- Definition

Amount of benefits expected to be paid in the five fiscal years after the fifth fiscal year following the latest fiscal year from a defined benefit plan.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (f)

-URI http://asc.fasb.org/extlink&oid=21915506&loc=d3e1928-114920

+ Details

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- Definition

Amount of benefits expected to be paid in the next fiscal year following the latest fiscal year from a defined benefit plan.

+ References

+ Details

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- Definition

Amount of benefits expected to be paid in the fifth fiscal year following the latest fiscal year from a defined benefit plan.

+ References

+ Details

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- Definition

Amount of benefits expected to be paid in the fourth fiscal year following the latest fiscal year from a defined benefit plan.

+ References

+ Details

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- Definition

Amount of benefits expected to be paid in the third fiscal year following the latest fiscal year from a defined benefit plan.

+ References

+ Details

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- Definition

Amount of benefits expected to be paid in the second fiscal year following the latest fiscal year from a defined benefit plan.

+ References

+ Details

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