COMMITMENTS AND CONTINGENCIES - LESSEE STATEMENT OF OPERATIONS INFORMATION (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2019
Lessee, Lease, Description [Line Items]
Operating lease costs	$ 23	$ 72
Finance lease costs:
Amortization of ROU assets	6	17
Interest on lease liabilities	47	141
Total finance lease costs	53	158
Short-term lease costs	3	5
Variable lease costs	156	396
Total lease costs	235	631
Southern California Gas Company [Member]
Lessee, Lease, Description [Line Items]
Operating lease costs	7	21
Finance lease costs:
Amortization of ROU assets	2	4
Interest on lease liabilities	0	0
Total finance lease costs	2	4
Short-term lease costs	0	0
Variable lease costs	1	7
Total lease costs	10	32
San Diego Gas and Electric Company [Member]
Lessee, Lease, Description [Line Items]
Operating lease costs	8	25
Finance lease costs:
Amortization of ROU assets	4	13
Interest on lease liabilities	47	141
Total finance lease costs	51	154
Short-term lease costs	1	1
Variable lease costs	155	389
Total lease costs	$ 215	$ 569