COMMITMENTS AND CONTINGENCIES - LESSEE CASH FLOW INFORMATION (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Lessee, Lease, Description [Line Items]
Increase in operating lease obligations for right-of-use assets	$ 1	$ 19
Increase in finance lease obligations for investment in PP&E	15	20
San Diego Gas and Electric Company [Member]
Lessee, Lease, Description [Line Items]
Increase in operating lease obligations for right-of-use assets	0	0
Increase in finance lease obligations for investment in PP&E	6	4
Southern California Gas Company [Member]
Lessee, Lease, Description [Line Items]
Increase in operating lease obligations for right-of-use assets	1	0
Increase in finance lease obligations for investment in PP&E	$ 9	$ 16

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.

No definition available.

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- Definition

Amount of increase in right-of-use asset obtained in exchange for finance lease liability.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 55
-Paragraph 53
-URI http://asc.fasb.org/extlink&oid=121568110&loc=SL77918982-209971

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (g)(2)
-URI http://asc.fasb.org/extlink&oid=121609121&loc=SL77918686-209980

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- Definition

Amount of increase in right-of-use asset obtained in exchange for operating lease liability.

+ References

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