GENERAL INFORMATION AND OTHER FINANCIAL DATA - INVENTORIES (Details) - USD ($) $ in Millions	Jun. 30, 2019	Dec. 31, 2018
Inventory [Line Items]
Natural gas	$ 47	$ 95
LNG	10	4
Materials and supplies	157	159
Inventory	214	258	[1]
SDG&E [Member]
Inventory [Line Items]
Natural gas	0	0
LNG	0	0
Materials and supplies	96	102
Inventory	96	102
SoCalGas [Member]
Inventory [Line Items]
Natural gas	28	92
LNG	0	0
Materials and supplies	47	42
Inventory	75	134
Sempra Mexico [Member]
Inventory [Line Items]
Natural gas	0	0
LNG	10	4
Materials and supplies	14	15
Inventory	24	19
Sempra LNG [Member]
Inventory [Line Items]
Natural gas	19	3
LNG	0	0
Materials and supplies	0	0
Inventory	$ 19	$ 3

[1] Derived from audited financial statements.