GENERAL INFORMATION AND OTHER FINANCIAL DATA - CAPITALIZED FINANCING COSTS (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Capitalized Financing Costs Disclosure [Line Items]
Capitalized interest costs	$ 55	$ 50	$ 114	$ 98
San Diego Gas and Electric Company [Member]
Capitalized Financing Costs Disclosure [Line Items]
Capitalized interest costs	28	26	58	53
Southern California Gas Company [Member]
Capitalized Financing Costs Disclosure [Line Items]
Capitalized interest costs	$ 15	$ 14	$ 31	$ 25