COMMITMENTS AND CONTINGENCIES - LEASE INFORMATION (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Lessee, Lease, Description [Line Items]
Fixed lease payments	$ 59	$ 47	$ 112	$ 97
Variable lease payments	1	0	1	0
Operating Lease, Lease Income	60	47	113	97
Depreciation expense	$ 12	$ 9	22	$ 19
San Diego Gas and Electric Company [Member]
Lessee, Lease, Description [Line Items]
Lease not yet commenced, 2021			3
Lease not yet commenced, 2022			10
Lease not yet commenced, 2023			10
Lease not yet commenced, 2024			10
Lease not yet commenced, 2025			10
Lease not yet commenced, thereafter			$ 101

Lessee, Operating Lease, Lease Not Yet Commenced, After Year Four

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- Definition

Lessee, Operating Lease, Lease Not Yet Commenced, Remainder of Fiscal Year

+ References

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Lessee, Operating Lease, Lease Not Yet Commenced, Year Four

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- Definition

Lessee, Operating Lease, Lease Not Yet Commenced, Year One

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- Definition

Lessee, Operating Lease, Lease Not Yet Commenced, Year Three

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Lessee, Operating Lease, Lease Not Yet Commenced, Year Two

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No definition available.

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No definition available.

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- Definition

Amount of operating lease income from lease payments and variable lease payments paid and payable to lessor. Includes, but is not limited to, variable lease payments not included in measurement of lease receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 30
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=124258985&loc=SL77919372-209981

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 6A
-URI http://asc.fasb.org/extlink&oid=124502072&loc=SL77927221-108306

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Amount of operating lease income from lease payments paid and payable to lessor. Excludes variable lease payments not included in measurement of lease receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 270
-SubTopic 10
-Section 50
-Paragraph 6A
-URI http://asc.fasb.org/extlink&oid=124502072&loc=SL77927221-108306

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- Definition

Amount of operating lease income from variable lease payments paid and payable to lessor, excluding amount included in measurement of lease receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 270
-SubTopic 10
-Section 50
-Paragraph 6A
-URI http://asc.fasb.org/extlink&oid=124502072&loc=SL77927221-108306

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-URI http://asc.fasb.org/extlink&oid=124258985&loc=SL77919372-209981

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- Definition

Amount of depreciation expense for lessor's underlying asset for which right to use has been conveyed to lessee under operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 30
-Section 50
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=124258985&loc=SL77919398-209981

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-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

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