Property, Plant and Equipment (Jointly Owned Utility Projects) (Details) - SCE - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Jointly Owned Utility Plant Interests [Line Items]
Nuclear Fuel (at amortized cost)	$ 131	$ 129
Eldorado
Jointly Owned Utility Plant Interests [Line Items]
Plant in Service	324
Construction Work in Progress	74
Accumulated Depreciation	39
Nuclear Fuel (at amortized cost)	0
Net Book Value	$ 359
Ownership Interest	79.00%
Pacific Intertie
Jointly Owned Utility Plant Interests [Line Items]
Plant in Service	$ 346
Construction Work in Progress	0
Accumulated Depreciation	74
Nuclear Fuel (at amortized cost)	0
Net Book Value	$ 272
Ownership Interest	50.00%
Palo Verde (nuclear)
Jointly Owned Utility Plant Interests [Line Items]
Plant in Service	$ 2,113
Construction Work in Progress	53
Accumulated Depreciation	1,609
Nuclear Fuel (at amortized cost)	131
Net Book Value	$ 688
Ownership Interest	16.00%
Total
Jointly Owned Utility Plant Interests [Line Items]
Plant in Service	$ 2,783
Construction Work in Progress	127
Accumulated Depreciation	1,722
Nuclear Fuel (at amortized cost)	131
Net Book Value	$ 1,319

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-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=115995737&loc=d3e659983-123033

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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

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- 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

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- Definition

The period end amount of construction work in progress at a jointly owned electricity generation plant.

+ References

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- Definition

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

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- Definition

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

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- 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://fasb.org/us-gaap/role/ref/legacyRef
-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=120391452&loc=d3e13212-122682

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