GENERAL INFORMATION AND OTHER FINANCIAL DATA - INVENTORIES (Details) - USD ($) $ in Millions	Jun. 30, 2020	Dec. 31, 2019
Inventory [Line Items]
Natural gas	$ 86	$ 110
LNG	7	9
Materials and supplies	174	158
Inventory	267	277	[1]
San Diego Gas and Electric Company [Member]
Inventory [Line Items]
Natural gas	0	1
LNG	0	0
Materials and supplies	101	93
Inventory	101	94	[1]
Southern California Gas Company [Member]
Inventory [Line Items]
Natural gas	64	90
LNG	0	0
Materials and supplies	54	46
Inventory	$ 118	$ 136	[1]

[1] Derived from audited financial statements.