GENERAL INFORMATION AND OTHER FINANCIAL DATA - OTHER INCOME, NET (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Other Income [Line Items]
Allowance for equity funds used during construction	$ 33	$ 35
Investment (losses) gains, net	12	(13)
Gains on interest rate and foreign exchange instruments, net	5	6
Foreign currency transaction (losses) gains, net	1	(19)
Non-service components of net periodic benefit cost	(25)	41
Interest on regulatory balancing accounts, net	18	1
Sundry, net	(3)	(13)
Total	41	38
San Diego Gas and Electric Company
Other Income [Line Items]
Allowance for equity funds used during construction	23	21
Non-service components of net periodic benefit cost	(4)	11
Interest on regulatory balancing accounts, net	10	1
Sundry, net	(1)	1
Total	28	34
Southern California Gas Company
Other Income [Line Items]
Allowance for equity funds used during construction	10	13
Non-service components of net periodic benefit cost	(19)	32
Interest on regulatory balancing accounts, net	8	0
Sundry, net	(7)	(11)
Total	$ (8)	34
IMG
Other Income [Line Items]
Foreign currency transaction (losses) gains, net		$ (11)