Property, Plant and Equipment (Jointly Owned Utility Projects) (Details) - SCE - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Jointly Owned Utility Plant Interests [Line Items]
Nuclear Fuel (at amortized cost)	$ 130	$ 126
Eldorado
Jointly Owned Utility Plant Interests [Line Items]
Plant in Service	245
Construction Work in Progress	13
Accumulated Depreciation	29
Nuclear Fuel (at amortized cost)	0
Net Book Value	$ 229
Ownership Interest	59.00%
Pacific Intertie
Jointly Owned Utility Plant Interests [Line Items]
Plant in Service	$ 217
Construction Work in Progress	73
Accumulated Depreciation	75
Nuclear Fuel (at amortized cost)	0
Net Book Value	$ 215
Ownership Interest	50.00%
Palo Verde (nuclear)
Jointly Owned Utility Plant Interests [Line Items]
Plant in Service	$ 2,024
Construction Work in Progress	63
Accumulated Depreciation	1,567
Nuclear Fuel (at amortized cost)	130
Net Book Value	$ 650
Ownership Interest	16.00%
Total
Jointly Owned Utility Plant Interests [Line Items]
Plant in Service	$ 2,486
Construction Work in Progress	149
Accumulated Depreciation	1,671
Nuclear Fuel (at amortized cost)	130
Net Book Value	$ 1,094

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=6877327&loc=d3e13212-122682

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