REGULATORY MATTERS - GENERAL RATE CASE (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended
	Apr. 30, 2020	Jun. 30, 2019	Mar. 31, 2019	Mar. 31, 2020
San Diego Gas and Electric Company [Member] | General Rate Case [Member]
General Rate Case [Line Items]
Tracked income tax expense liability				$ 86
Southern California Gas Company [Member] | General Rate Case [Member]
General Rate Case [Line Items]
Tracked income tax expense liability				$ 89
2019 GRC FD [Member] | San Diego Gas and Electric Company [Member]
General Rate Case [Line Items]
Retroactive after-tax earnings impact		$ 30	$ 36
2019 GRC FD [Member] | Southern California Gas Company [Member]
General Rate Case [Line Items]
Retroactive after-tax earnings impact		$ 46	$ 84
Subsequent Event [Member] | 2019 GRC FD - 2022 Requirement [Member] | San Diego Gas and Electric Company [Member]
General Rate Case [Line Items]
GRC requested revenue requirement	$ 106
Subsequent Event [Member] | 2019 GRC FD - 2022 Requirement [Member] | Southern California Gas Company [Member]
General Rate Case [Line Items]
GRC requested revenue requirement	155
Subsequent Event [Member] | 2019 GRC FD - 2023 Requirement [Member] | San Diego Gas and Electric Company [Member]
General Rate Case [Line Items]
GRC requested revenue requirement	108
Subsequent Event [Member] | 2019 GRC FD - 2023 Requirement [Member] | Southern California Gas Company [Member]
General Rate Case [Line Items]
GRC requested revenue requirement	$ 137