The actual asset allocation of fair value of publicly traded equity investments.

No definition available.

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- Definition

This element represents the employee retiring age in order to be eligible for the plan.

+ References

No definition available.

+ Details

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Data Type:	xbrli:durationItemType
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- Definition

This element represents the minimum service period required, for the employee to be eligible for the benefits.

+ References

No definition available.

+ Details

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- Definition

This element represents the percentage of decline in the market value of investments held within plan trusts.

+ References

No definition available.

+ Details

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Namespace Prefix:	eix_
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- Definition

This element represents the permissible range of asset class portfolio weights.

+ References

No definition available.

+ Details

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- Definition

Target allocation percentage of investments in alternative investments to total plan assets presented on a weighted-average basis as of the measurement date of the latest statement of financial position. Alternative investments include investments in private equities, hedge funds and fixed income securities.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Target allocation percentage of investments in non U.S. equity securities to total plan assets presented on a weighted-average basis as of the measurement date of the latest statement of financial position.

+ References

No definition available.

+ Details

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- Definition

Target allocation percentage of other investments not elsewhere specifically mentioned in the taxonomy to total plan assets presented on a weighted-average basis as of the measurement date of the latest statement of financial position. Alternative investments include investments in private equities, hedge funds and fixed income securities.

+ References

No definition available.

+ Details

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- Definition

Target allocation percentage of investments in U.S. equity securities to total plan assets presented on a weighted-average basis as of the measurement date of the latest statement of financial position.

+ References

No definition available.

+ Details

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- Definition

This element represents the percentage of premium included in estimated rate of return of equity securities (as a percent)

+ References

No definition available.

+ Details

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- Definition

This element represents the percentage of premium included in estimated rate of return of public equity and hedge funds.

+ References

No definition available.

+ Details

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- Definition

After tax net amount of gain (loss) that are not yet recognized as a component of net periodic benefit cost, and that are recognized as increases (decreases) in other comprehensive income as they arise.

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

The amounts in accumulated other comprehensive income related to gains and losses that are not recognized immediately and are expected to be recognized as components of net periodic benefit cost over the next fiscal year that follows the most recent annual statement of financial position presented.

+ 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 (s)

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-Publisher FASB

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-Number 158

-Paragraph 7

-Subparagraph d

-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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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 132R

-Paragraph 5

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-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.

+ Details

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Period Type:	duration

- Definition

The amounts in accumulated other comprehensive income related to prior service cost or credit expected to be recognized as components of net periodic benefit cost over the next fiscal year that follows the most recent annual statement of financial position presented.

+ References

+ Details

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- Details

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- Definition

Amount of effect of a one-percentage-point decrease in the assumed health care cost trend rates on the accumulated postretirement benefit obligation for health care benefits.

+ References

+ Details

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Period Type:	duration

- Definition

Amount of effect of a one-percentage-point decrease in the assumed health care cost trend rates on the aggregate of the service and interest cost components of net periodic postretirement health care benefit costs.

+ References

+ Details

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Period Type:	duration

- Definition

The effect of a one-percentage-point increase in the assumed health care cost trend rates on the accumulated postretirement benefit obligation for health care benefits.

+ References

+ Details

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- Definition

The effect of a one-percentage-point increase in the assumed health care cost trend rates on the aggregate of the service and interest cost components of net periodic postretirement health care benefit costs.

+ References

+ Details

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- Definition

The employer's best estimate, as soon as it can be reasonably determined, of contributions expected to be paid to the plan during the next fiscal year beginning after the date of the latest statement of financial position. Estimated contributions may be presented in the aggregate combining (1) contributions required by funding regulations or laws, (2) discretionary contributions, and (3) noncash contributions.

+ References

+ Details

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- Definition

Target allocation of investments of this type to total plan assets presented on a weighted average basis.

+ References

+ Details

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- Definition

This represents the noncurrent liability for underfunded plans recognized in the balance sheet that is associated with the defined benefit pension plans and other postretirement defined benefit plans.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 132R

-Paragraph 6

-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.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 3

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-Name Accounting Standards Codification

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-Name Accounting Standards Codification

-Topic 210

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-Paragraph 1

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Reference 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 45

-Paragraph 2

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Compensation and Benefit Plans (Pension and Postretirement Benefits Textual) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2008
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Retirement liabilities for EME employees	$ 2,614	$ 2,715
Defined Benefit Plan, Assets, Target Allocations [Abstract]
Percentage of premium included in estimated rate of return of equity securities	5.00%
Percentage of premium included in estimated rate of return of public equity and hedge funds	2.00%
Pension Plans
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Net loss to be reclassified	(13)
Estimated future employer contributions in 2013	220
Percentage of decline in market value of investments held in trust				35.00%
Retirement liabilities for EME employees	1,387	1,329
Defined Benefit Plan, Assets, Target Allocations [Abstract]
Target asset allocation percentage of US equity securities	30.00%	30.00%
Target asset allocation percentage of non US equity securities	16.00%	16.00%
Target asset allocation percentage of fixed income securities	35.00%	35.00%
Target asset allocation percentage of alternative investments	15.00%	15.00%
Target asset allocation percentage of other investments	4.00%	4.00%
Permissible Range of Asset Class Portfolio Weights	3.00%
Asset allocations of publicly traded equity investments	66.00%	69.00%
Postretirement Benefits Other Than Pensions
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Net gain (loss) recognized on other comprehensive income	0	1	(1)
Amortization of prior service credit	0	0	1
Estimated future employer contributions in 2013	30
Percentage of decline in market value of investments held in trust				33.00%
Retirement eligibility age	55 years
Minimum service period for eligibility	10 years
Retirement liabilities for EME employees	642	964
Defined Benefit Plan, Effect of One-Percentage Point Change in Assumed Health Care Cost Trend Rates [Abstract]
Effect of one percentage point increase on accumulated benefit obligation	276
Effect of one percentage point decrease on accumulated benefit obligation	(228)
Effect of one percentage point increase on aggregate service and interest costs	13
Effect of one percentage point decrease on aggregate service and interest costs	(11)
Defined Benefit Plan, Assets, Target Allocations [Abstract]
Target asset allocation percentage of US equity securities	41.00%	41.00%
Target asset allocation percentage of non US equity securities	17.00%	17.00%
Target asset allocation percentage of fixed income securities	34.00%	34.00%
Target asset allocation percentage of alternative investments	7.00%	7.00%
Target asset allocation percentage of other investments	1.00%	1.00%
Asset allocations of publicly traded equity investments	66.00%	69.00%
Edison Mission Energy
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Retirement liabilities for EME employees	80
Southern California Edison
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Retirement liabilities for EME employees	2,245	2,461
Southern California Edison \| Pension Plans
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Net loss to be reclassified	(8)
Estimated future employer contributions in 2013	182
Retirement liabilities for EME employees	1,108	1,135
Southern California Edison \| Postretirement Benefits Other Than Pensions
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Net loss to be reclassified	0
Retirement liabilities for EME employees	634	829
Defined Benefit Plan, Effect of One-Percentage Point Change in Assumed Health Care Cost Trend Rates [Abstract]
Effect of one percentage point increase on accumulated benefit obligation	275
Effect of one percentage point decrease on accumulated benefit obligation	(227)
Effect of one percentage point increase on aggregate service and interest costs	13
Effect of one percentage point decrease on aggregate service and interest costs	(11)
Maximum \| Postretirement Benefits Other Than Pensions
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Net loss to be reclassified	$ 1