Property, Plant and Equipment (Jointly Owned Utility Projects) (Details) - SCE - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Jointly Owned Utility Plant Interests [Line Items]
Nuclear Fuel (at amortized cost)	$ 129	$ 130
Eldorado
Jointly Owned Utility Plant Interests [Line Items]
Plant in Service	257
Construction Work in Progress	94
Accumulated Depreciation	35
Nuclear Fuel (at amortized cost)	0
Net Book Value	$ 316
Ownership Interest	80.00%
Pacific Intertie
Jointly Owned Utility Plant Interests [Line Items]
Plant in Service	$ 248
Construction Work in Progress	80
Accumulated Depreciation	72
Nuclear Fuel (at amortized cost)	0
Net Book Value	$ 256
Ownership Interest	50.00%
Palo Verde (nuclear)
Jointly Owned Utility Plant Interests [Line Items]
Plant in Service	$ 2,065
Construction Work in Progress	61
Accumulated Depreciation	1,586
Nuclear Fuel (at amortized cost)	129
Net Book Value	$ 669
Ownership Interest	16.00%
Total
Jointly Owned Utility Plant Interests [Line Items]
Plant in Service	$ 2,570
Construction Work in Progress	235
Accumulated Depreciation	1,693
Nuclear Fuel (at amortized cost)	129
Net Book Value	$ 1,241

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.

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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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