SAN ONOFRE NUCLEAR GENERATING STATION (Details) - USD ($) $ in Millions	6 Months Ended
Jun. 30, 2021	Dec. 31, 2020
Jointly Owned Utility Plant Interests [Line Items]
Anticipated term of dismantlement work	10 years
San Diego Gas and Electric Company [Member]
Jointly Owned Utility Plant Interests [Line Items]
Percent of dismantlement work expense (as a percent)	20.00%
ARO related to decommissioning costs	$ 563
Cost study estimate decommissioning escalated	$ 886
Jointly Owned Nuclear Power Plant [Member] \| San Diego Gas and Electric Company [Member]
Jointly Owned Utility Plant Interests [Line Items]
Jointly owned utility plant, proportionate ownership share (as a percent)	20.00%
SONGS 2 and 3 Decommissioning [Member] \| San Diego Gas and Electric Company [Member]
Jointly Owned Utility Plant Interests [Line Items]
Nuclear decommissioning trust authorized withdrawal amount		$ 89

Authorized Recovery Amount, Nuclear Decommissioning Trust Funding.

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- Definition

Total Estimated Nuclear Decommissioning Costs, Latest Cost Study Escalated.

+ References

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- Definition

Decommissioning Liability

+ References

No definition available.

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- Definition

Environmental Exit Costs, Anticipated Cost, Percentage

+ References

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- Definition

Environmental Exit Costs, Anticipated Term

+ References

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- Definition

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

No definition available.

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- Definition

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

+ References

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=122136288&loc=d3e659983-123033

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