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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

This element represents the collateralized mortgage obligations and other asset backed securities.

+ Details

Name:	eix_CollateralizedMortgageObligationsAndOtherAssetBackedSecurities
Namespace Prefix:	eix
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

This element represents the percentage of equity investments located in United States.

+ Details

Name:	eix_EquityInvestmentsPercentage
Namespace Prefix:	eix
Data Type:	us-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

This element represents the fair value of financial assets as of the statement of financial position.

+ Details

Name:	eix_FairValueAssetsMeasuredOnRecurringBasisFinancialAssets
Namespace Prefix:	eix
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

This element represents a certain statement of financial position asset caption which represents long-term disability plan, measured at fair value on a recurring basis.

+ Details

Name:	eix_FairValueAssetsMeasuredOnRecurringBasisLongTermDisabilityPlan
Namespace Prefix:	eix
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

This element represents a certain statement of financial position asset caption which represents money market funds, measured at fair value on a recurring basis.

+ Details

Name:	eix_FairValueAssetsMeasuredOnRecurringBasisMoneyMarketFunds
Namespace Prefix:	eix
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

This element represents a certain statement of financial position asset caption which represents nuclear decommissioning trusts, measured at fair value on a recurring basis. This element excludes receivables and payables on investments.

+ Details

Name:	eix_FairValueAssetsMeasuredOnRecurringBasisNuclearDecommissioningTrustsExcludingReceivablesAndPayables
Namespace Prefix:	eix
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

Name:	eix_FairValueDisclosuresLevel3RollForward
Namespace Prefix:	eix
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

This element represents the fair value of financial liabilities as of the statement of position.

+ Details

Name:	eix_FairValueLiabilitiesMeasuredOnRecurringBasisFinancialLiabilities
Namespace Prefix:	eix
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

This element represents total gains or losses for the period (realized and unrealized), included in regulatory assets and liabilities measured at fair value on a recurring basis using unobservable inputs (level 3).

+ Details

Name:	eix_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInRegulatoryAssetsAndLiabilities
Namespace Prefix:	eix
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Purchases that have taken place during the period in relation to assets measured at fair value and categorized within Level 3 of the fair value hierarchy.

+ Details

Name:	eix_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases
Namespace Prefix:	eix
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Settlements that have taken place during the period in relation to assets measured at fair value and categorized within Level 3 of the fair value hierarchy.

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Name:	eix_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements
Namespace Prefix:	eix
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

This element represents the fair value, Net, financial assets and liabilities as of the statement of financial position.

+ Details

Name:	eix_FairValueNetFinancialAssetsAndLiabilitiesMeasuredOnRecurringBasis
Namespace Prefix:	eix
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

This element represents the change during the period in unrealized gains (losses) for financial instruments, held at the end of the period, with unobservable inputs (level 3).

+ Details

Name:	eix_IncreaseDecreaseDuringPeriodInUnrealizedGainsLossesRelatedToLevel3FinancialInstrumentsHeldAtPeriodEnd
Namespace Prefix:	eix
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

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Name:	eix_LiabilitiesAtFairValuesAbstract
Namespace Prefix:	eix
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Balance Type:	na
Period Type:	duration

- Details

Name:	eix_NetRealizedOrUnrealizedGainLossAbstract
Namespace Prefix:	eix
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Interest and dividends receivables and receivables related to pending securities sales and payables related to pending securities purchases as of the balance sheet date.

+ Details

Name:	eix_ReceivablesPayablesNetRelatedToInvestments
Namespace Prefix:	eix
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

This element represents the amounts of unrealized gain or loss related to financial instruments with unobservable inputs (level 3) reported in competitive power generation revenue.

+ Details

Name:	eix_UnrealizedGainLossRelatedToLevel3FinancialInstrumentsReportedWithinCompetitivePowerGenerationRevenue
Namespace Prefix:	eix
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Carrying amount as of the balance sheet date of amounts which could be received based on the terms of the insurance contract upon surrendering life policies owned by the entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 17
-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name FASB Technical Bulletin (FTB)
-Number 85-4
-Paragraph 2

+ Details

Name:	us-gaap_CashSurrenderValueOfLifeInsurance
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

This element represents a certain statement of financial position asset caption which represents a class of assets, or which may include an individual asset, measured at fair value on a recurring basis.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 157
-Paragraph 32
-Subparagraph a

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Name:	us-gaap_FairValueAssetsMeasuredOnRecurringBasisDerivativeFinancialInstrumentsAssets
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

This element represents a certain statement of financial position liability caption which represents a class of liabilities, or which may include an individual liability, measured at fair value on a recurring basis.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 157
-Paragraph 32
-Subparagraph a

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Name:	us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisDerivativeFinancialInstrumentsLiabilities
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

This element represents total gains or losses for the period (realized and unrealized), arising from assets measured at fair value on a recurring basis using unobservable inputs (Level 3), which are included in earnings or resulted in a change in net asset value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 157
-Paragraph 32
-Subparagraph c(1)

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Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
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Period Type:	duration

- Definition

This element represents total gains or losses for the period (realized and unrealized), arising from assets measured at fair value on a recurring basis using unobservable inputs (Level 3), which are included in other comprehensive income (a separate component of shareholders' equity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 157
-Paragraph 32
-Subparagraph c(1)

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Name:	us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncome
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

This element represents [net] transfers in to and out of assets measured at fair value on a recurring basis using unobservable inputs (Level 3) which have taken place during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 157
-Paragraph 32
-Subparagraph c(3)

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Name:	us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersNet
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

This element represents an asset measured at fair value using significant unobservable inputs (Level 3) which is required for reconciliation purposes of beginning and ending balances.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 157
-Paragraph 32
-Subparagraph c

+ Details

Name:	us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Fair Value Measurements (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010	Dec. 31, 2010
Liabilities at Fair Value
Percentage of equity investments located in the United States (as a percent)	68.00%		68.00%		67.00%
Collateralized mortgage obligations and other asset backed securities			$ 27		$ 27
Receivables (payables) net related to investments	11		11		(5)
Cash surrender value of life insurance	31		31		31
Total realized/unrealized gains (losses):
Unrealized gain loss related to Level 3 financial instruments reported within competitive power generation revenue	14	(2)	8	32
Level 1
Assets at Fair Value
Money market funds	743		743		1,100
Long-term disability plan	9		9		9
Nuclear decommissioning trusts	2,375		2,375		2,245
Total assets	3,133		3,133		3,363
Liabilities at Fair Value
Net assets (liabilities)	3,133		3,133		3,363
Level 1 \| Stocks
Assets at Fair Value
Nuclear decommissioning trusts	2,062		2,062		2,029
Level 1 \| U.S. government and agency securities
Assets at Fair Value
Nuclear decommissioning trusts	309		309		215
Level 1 \| Short-term investments, primarily cash equivalents
Assets at Fair Value
Nuclear decommissioning trusts	4		4		1
Level 1 \| Commodity contracts.
Assets at Fair Value
Derivative contracts	6		6		9
Level 1 \| Natural gas
Assets at Fair Value
Derivative contracts					1
Level 1 \| Fuel oil
Assets at Fair Value
Derivative contracts	6		6		8
Level 2
Assets at Fair Value
Nuclear decommissioning trusts	1,271		1,271		1,240
Total assets	1,381		1,381		1,379
Liabilities at Fair Value
Total liabilities	270		270		316
Net assets (liabilities)	1,111		1,111		1,063
Level 2 \| Municipal bonds
Assets at Fair Value
Nuclear decommissioning trusts	812		812		790
Level 2 \| U.S. government and agency securities
Assets at Fair Value
Nuclear decommissioning trusts	118		118		73
Level 2 \| Corporate bonds
Assets at Fair Value
Nuclear decommissioning trusts	310		310		346
Level 2 \| Short-term investments, primarily cash equivalents
Assets at Fair Value
Nuclear decommissioning trusts	31		31		31
Level 2 \| Commodity contracts.
Assets at Fair Value
Derivative contracts	110		110		139
Liabilities at Fair Value
Derivative contracts	248		248		300
Level 2 \| Electricity
Assets at Fair Value
Derivative contracts	44		44		70
Liabilities at Fair Value
Derivative contracts	9		9		13
Level 2 \| Natural gas
Assets at Fair Value
Derivative contracts	65		65		69
Liabilities at Fair Value
Derivative contracts	239		239		286
Level 2 \| Coal
Assets at Fair Value
Derivative contracts	1		1
Liabilities at Fair Value
Derivative contracts					1
Level 2 \| Interest rate contracts.
Liabilities at Fair Value
Derivative contracts	22		22		16
Level 3
Assets at Fair Value
Total assets	283		283		492
Liabilities at Fair Value
Total liabilities	558		558		395
Net assets (liabilities)	(275)		(275)		97
Fair Value Disclosures Level 3
Fair value, net asset (liabilities) at beginning of period	(44)	(397)	97	62	62
Total realized/unrealized gains (losses):
Included in earnings	18	(18)	18	27
Included in regulatory assets and liabilities	(247)	(294)	(382)	(781)
Included in accumulated other comprehensive income	(4)	(2)	(3)	4
Purchases	22	26	28	32
Settlements	(20)	(24)	(31)	(52)
Transfers in or out of Level 3		6	(2)	5
Fair value, net liability at end of period	(275)	(703)	(275)	(703)
Change during the period in unrealized losses related to assets and liabilities held at the end of the period	(226)	(287)	(368)	(717)
Level 3 \| Commodity contracts.
Assets at Fair Value
Derivative contracts	283		283		492
Liabilities at Fair Value
Derivative contracts	558		558		395
Level 3 \| Electricity
Assets at Fair Value
Derivative contracts	231		231		363
Liabilities at Fair Value
Derivative contracts	71		71		40
Level 3 \| Natural gas
Assets at Fair Value
Derivative contracts	11		11		11
Liabilities at Fair Value
Derivative contracts	6		6		11
Level 3 \| Tolling
Assets at Fair Value
Derivative contracts	41		41		118
Liabilities at Fair Value
Derivative contracts	481		481		344
Netting and Collateral
Assets at Fair Value
Total assets	(40)		(40)		(70)
Liabilities at Fair Value
Total liabilities	(10)		(10)		(26)
Net assets (liabilities)	(30)		(30)		(44)
Netting and Collateral \| Commodity contracts.
Assets at Fair Value
Derivative contracts	(40)		(40)		(70)
Liabilities at Fair Value
Derivative contracts	(10)		(10)		(26)
Netting and Collateral \| Electricity
Assets at Fair Value
Derivative contracts	(33)		(33)		(61)
Liabilities at Fair Value
Derivative contracts	(9)		(9)		(21)
Netting and Collateral \| Natural gas
Assets at Fair Value
Derivative contracts					(1)
Liabilities at Fair Value
Derivative contracts	(1)		(1)		(4)
Netting and Collateral \| Fuel oil
Assets at Fair Value
Derivative contracts	(6)		(6)		(8)
Netting and Collateral \| Coal
Assets at Fair Value
Derivative contracts	(1)		(1)
Liabilities at Fair Value
Derivative contracts					(1)
Total
Assets at Fair Value
Money market funds	743		743		1,100
Long-term disability plan	9		9		9
Nuclear decommissioning trusts	3,646		3,646		3,485
Total assets	4,757		4,757		5,164
Liabilities at Fair Value
Total liabilities	818		818		685
Net assets (liabilities)	3,939		3,939		4,479
Total \| Stocks
Assets at Fair Value
Nuclear decommissioning trusts	2,062		2,062		2,029
Total \| Municipal bonds
Assets at Fair Value
Nuclear decommissioning trusts	812		812		790
Total \| U.S. government and agency securities
Assets at Fair Value
Nuclear decommissioning trusts	427		427		288
Total \| Corporate bonds
Assets at Fair Value
Nuclear decommissioning trusts	310		310		346
Total \| Short-term investments, primarily cash equivalents
Assets at Fair Value
Nuclear decommissioning trusts	35		35		32
Total \| Commodity contracts.
Assets at Fair Value
Derivative contracts	359		359		570
Liabilities at Fair Value
Derivative contracts	796		796		669
Total \| Electricity
Assets at Fair Value
Derivative contracts	242		242		372
Liabilities at Fair Value
Derivative contracts	71		71		32
Total \| Natural gas
Assets at Fair Value
Derivative contracts	76		76		80
Liabilities at Fair Value
Derivative contracts	244		244		293
Total \| Tolling
Assets at Fair Value
Derivative contracts	41		41		118
Liabilities at Fair Value
Derivative contracts	481		481		344
Total \| Interest rate contracts.
Liabilities at Fair Value
Derivative contracts	$ 22		$ 22		$ 16