COMMITMENTS AND CONTINGENCIES - LEASES BALANCE SHEET INFORMATION (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Lessee, Lease, Description [Line Items]
Right-of-use assets – operating leases	$ 591
Finance leases, property plant and equipment	1,353
Finance leases, accumulated depreciation	(64)
Finance leases, property plant and equipment, net	1,289
Total right-of-use assets	1,880
Operating lease, other current liabilities	52
Operating lease, deferred credits and other	445
Total lease liabilities	497
Finance lease, current portion of long-term debt and finance leases	26
Long-term lease liabilities	1,263
Total finance leases	1,289
Lease liabilities	$ 1,786
Operating lease, weighted-average remaining lease term	13 years
Finance lease, weighted-average remaining lease term	19 years
Operating lease, weighted-average discount rate (as a percent)	6.01%
Finance lease, weighted-average discount rate (as a percent)	14.76%
San Diego Gas and Electric Company [Member]
Lessee, Lease, Description [Line Items]
Right-of-use assets – operating leases	$ 130
Finance leases, property plant and equipment	1,326
Finance leases, accumulated depreciation	(57)
Finance leases, property plant and equipment, net	1,269
Total right-of-use assets	1,399
Operating lease, other current liabilities	27
Operating lease, deferred credits and other	102
Total lease liabilities	129
Finance lease, current portion of long-term debt and finance leases	20
Long-term lease liabilities	1,250
Total finance leases	1,270
Lease liabilities	$ 1,399
Operating lease, weighted-average remaining lease term	6 years
Finance lease, weighted-average remaining lease term	20 years
Operating lease, weighted-average discount rate (as a percent)	3.55%
Finance lease, weighted-average discount rate (as a percent)	14.83%
Southern California Gas Company [Member]
Lessee, Lease, Description [Line Items]
Right-of-use assets – operating leases	$ 94
Finance leases, property plant and equipment	27
Finance leases, accumulated depreciation	(7)
Finance leases, property plant and equipment, net	20
Total right-of-use assets	114
Operating lease, other current liabilities	18
Operating lease, deferred credits and other	75
Total lease liabilities	93
Finance lease, current portion of long-term debt and finance leases	6
Long-term lease liabilities	13
Total finance leases	19	$ 3
Lease liabilities	$ 112
Operating lease, weighted-average remaining lease term	6 years
Finance lease, weighted-average remaining lease term	6 years
Operating lease, weighted-average discount rate (as a percent)	3.73%
Finance lease, weighted-average discount rate (as a percent)	3.23%
Maximum [Member]
Lessee, Lease, Description [Line Items]
Operating lease renewal period	25 years
Annual increase in rent, percent	4.00%
Minimum [Member]
Lessee, Lease, Description [Line Items]
Operating lease termination period	1 year
Annual increase in rent, percent	2.00%