COMMITMENTS AND CONTINGENCIES - CONTRACTUAL COMMITMENTS (Details) $ in Millions	9 Months Ended
	Sep. 30, 2019 USD ($)
Sempra LNG [Member] | Liquefied Natural Gas Contracts [Member]
Loss Contingencies [Line Items]
Change in 2019	$ (281)
Change in 2020	(9)
Change in 2021	(16)
Change in 2022	(8)
Change in 2023	(1)
Change thereafter	(24)
San Diego Gas and Electric Company [Member] | Purchased-Power Contracts [Member]
Loss Contingencies [Line Items]
Change in 2019	13
Change in 2020	45
Change in 2021	52
Change in 2022	69
Change in 2023	74
Change thereafter	119
Increase purchase-power contracts	372
OMEC LLC [Member] | San Diego Gas and Electric Company [Member] | Purchased-Power Contracts [Member]
Loss Contingencies [Line Items]
Increase purchase-power contracts	$ 262