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

No definition available.

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- Definition

Defined Benefit Plan, Eligibility Age1

+ References

No definition available.

+ Details

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- Definition

Defined Benefit Plan, Minimum Service Period for Eligibility

+ References

No definition available.

+ Details

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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

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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Balance Type:	na
Period Type:	instant

- 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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Namespace Prefix:	eix_
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Period Type:	instant

- Definition

This element represents the historical period which is used to compute the expected volatility of the equity award.

+ References

No definition available.

+ Details

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Data Type:	xbrli:durationItemType
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Period Type:	duration

- Definition

Amount of contributions expected to be received by defined benefit plan from employer in next fiscal year following latest fiscal year.

+ 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 (g)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

+ Details

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

- Definition

Percentage of target investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one 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 (d)(5)(i)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

+ Details

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- Definition

The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

+ Details

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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

+ Details

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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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Period Type:	duration

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- Details

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Compensation and Benefit Plans (Textual) (Details) - USD ($) shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Assumed average equity risk premium (percent)	5.00%
Forecasted return on private equity and opportunistic investments (percent)	2.00%
Performance incentive plan award (shares)	66
Share-based compensation, shares available for grant	30
Stock options
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Stock options, expiration period, years	10 years
Stock options, vesting period, years	4 years
Volatility period	68 months	71 months	71 months
Pension Plans
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Expected contributions	$ 66
Permissible range of asset class weights (percent)	3.00%
Publicly traded equity investments located in the US (percent)	67.00%	69.00%
Pension Plans \| US Equities
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target plan asset allocations (percent)	29.00%
Pension Plans \| Non-US Equities
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target plan asset allocations (percent)	17.00%
Pension Plans \| Fixed Income
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target plan asset allocations (percent)	35.00%
Pension Plans \| Opportunistic Alternative Investments
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target plan asset allocations (percent)	15.00%
Pension Plans \| Other Investments
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target plan asset allocations (percent)	4.00%
Postretirement Benefits Other Than Pensions
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Expected contributions	$ 12
Eligibility age	55 years
Service period for eligibility (at least) (years)	10 years
Publicly traded equity investments located in the US (percent)	61.00%	63.00%
Postretirement Benefits Other Than Pensions \| US Equities
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target plan asset allocations (percent)	58.00%
Postretirement Benefits Other Than Pensions \| Fixed Income
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target plan asset allocations (percent)	29.00%
Postretirement Benefits Other Than Pensions \| Opportunistic Alternative Investments
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target plan asset allocations (percent)	13.00%
Voluntary Employee Beneficiary Association (VEBA) \| Fixed Income
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target plan asset allocations (percent)	85.00%
Voluntary Employee Beneficiary Association (VEBA) \| Opportunistic Alternative Investments
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target plan asset allocations (percent)	5.00%
Voluntary Employee Beneficiary Association (VEBA) \| Global Equities
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target plan asset allocations (percent)	10.00%
SCE \| Pension Plans
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Expected contributions	$ 50