COMMITMENTS AND CONTINGENCIES - LEASE INFORMATION (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended	9 Months Ended
Jul. 31, 2021	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Lessee, Lease, Description [Line Items]
Reduction in carrying value	$ 44
Net investment in sales-type lease	60
Selling profit	$ 16
Income recognized at lease commencement		$ 16	$ 0	$ 16	$ 1
Interest income		2	0	2	1
Total revenues from sales-type leases(1)		18	0	18	2
Fixed lease payments		80	48	192	145
Variable lease payments		2	1	3	1
Total revenues from operating leases(1)		82	49	195	146
Depreciation expense		$ 13	$ 10	35	$ 29
San Diego Gas and Electric Company [Member]
Lessee, Lease, Description [Line Items]
Lease not yet commenced, 2021				1
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				$ 103

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

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

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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.

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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.

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

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

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Amount of profit (loss) for sales-type lease and (loss) for direct financing lease recognized at commencement.

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Amount of sales-type lease initial direct cost recognized as expense at commencement date.

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Amount of profit (loss) recognized at commencement from sales-type lease.

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