Jointly Owned Utility Plant, Nuclear Fuel

No definition available.

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Namespace Prefix:	eix_
Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- Definition

The estimated selling price of the utility's investment in a jointly owned generating facility.

+ References

No definition available.

+ Details

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Namespace Prefix:	eix_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The period end amount owned by the reporting utility of a jointly owned utility plant in service.

+ References

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

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 10

-Section C

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 980

-SubTopic 360

-Section S99

-Paragraph 1

-Subparagraph (SAB TOPIC 10.C)

-URI http://asc.fasb.org/extlink&oid=6500719&loc=d3e659983-123033

+ Details

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

- Definition

The total period end amount of plant in service and construction in progress net of accumulated depreciation for the utility's share of jointly owned electricity generation plant.

+ References

+ Details

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Balance Type:	debit
Period Type:	instant

- Definition

The period end amount of accumulated depreciation in a jointly owned electricity generation plant.

+ References

+ Details

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

- Definition

The proportionate share of interest (percent) in a jointly owned utility plant.

+ References

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The carrying amount as of the balance sheet of nuclear fuel held as property plant and equipment. This amount is net of amortization based on the energy produced over the life of the fuel.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.13(b))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

Name:	us-gaap_NuclearFuelNetOfAmortization
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Period end book value of accumulated depreciation on property, plant and equipment (PPE) that is owned by the regulated operations of the public utility.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Period end amount of construction work in progress in public utility.

+ References

No definition available.

+ Details

Name:	us-gaap_PublicUtilitiesPropertyPlantAndEquipmentConstructionWorkInProgress
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Period end amount of property, plant and equipment (PPE) related to utility distribution.

+ References

No definition available.

+ Details

Name:	us-gaap_PublicUtilitiesPropertyPlantAndEquipmentDistribution
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Period end amount of property, plant and equipment (PPE) related to generation or processing owned by public utility.

+ References

No definition available.

+ Details

Name:	us-gaap_PublicUtilitiesPropertyPlantAndEquipmentGenerationOrProcessing
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Period end amount of total net PPE.

+ References

No definition available.

+ Details

Name:	us-gaap_PublicUtilitiesPropertyPlantAndEquipmentNet
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Period end book value of other property, plant and equipment (PPE) owned (but not classified elsewhere) by the public utility.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Period end amount of total gross PPE.

+ References

No definition available.

+ Details

Name:	us-gaap_PublicUtilitiesPropertyPlantAndEquipmentPlantInService
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

Name:	us-gaap_PublicUtilitiesPropertyPlantAndEquipmentPlantInServiceAbstract
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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Period end amount of property, plant and equipment (PPE) related to utility transmission owned by public utility.

+ References

No definition available.

+ Details

Name:	us-gaap_PublicUtilitiesPropertyPlantAndEquipmentTransmission
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
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Property, Plant and Equipment (Details) (USD $) In Millions, unless otherwise specified			0 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Nov. 08, 2010 Southern California Edison Company	Dec. 31, 2011 Southern California Edison Company	Dec. 31, 2011 Southern California Edison Company Eldorado	Dec. 31, 2011 Southern California Edison Company Pacific Intertie	Dec. 31, 2011 Southern California Edison Company Four Corners Units 4 and 5 (coal)	Dec. 31, 2011 Southern California Edison Company Mohave (coal)	Dec. 31, 2011 Southern California Edison Company Palo Verde (nuclear)	Dec. 31, 2011 Southern California Edison Company San Onofre (nuclear)
Utility plant, at original cost:
Transmission	$ 6,109	$ 5,811
Distribution	15,938	14,878
Generation	4,063	3,371
General plant and other	3,951	3,377
Accumulated depreciation	(6,894)	(6,319)
Total utility property, plant and equipment, before construction work in progress and nuclear fuel	23,167	21,118
Construction work in progress	3,922	3,291		471	4	2	17	24	54	370
Nuclear fuel, at amortized cost	480	369		480					138	342
Total property, plant and equipment	27,569	24,778
Plant in Service				8,177	71	189	589	327	1,803	5,198
Construction Work in Progress	3,922	3,291		471	4	2	17	24	54	370
Accumulated Depreciation				6,463	13	68	519	287	1,465	4,111
Nuclear Fuel					0	0	0	0
Net Book Value				2,665	62	123	87	64	530	1,799
Ownership Interest (as a percent)					60.00%	50.00%	48.00%	56.00%	16.00%	78.00%
Sale price related to ownership interest			$ 294