GENERAL INFORMATION AND OTHER FINANCIAL DATA - PENSION AND OTHER POSTRETIREMENT BENEFITS (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Pension benefits
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 27	$ 36	$ 110	$ 109
Interest cost	29	28	88	84
Expected return on assets	(46)	(44)	(137)	(130)
Amortization of:
Prior service cost (credit)	3	3	8	8
Actuarial loss (gain)	8	12	19	34
Settlement charges			0	7
Net periodic benefit cost (credit)	21	35	88	112
Regulatory adjustments	87	73	84	66
Total expense recognized	108	108	172	178
Pension benefits | San Diego Gas and Electric Company
Defined Benefit Plan Disclosure [Line Items]
Service cost	8	9	28	26
Interest cost	7	6	20	18
Expected return on assets	(13)	(11)	(35)	(36)
Amortization of:
Actuarial loss (gain)	0	1	1	2
Net periodic benefit cost (credit)	2	5	14	10
Regulatory adjustments	24	21	26	30
Total expense recognized	26	26	40	40
Pension benefits | Southern California Gas Company
Defined Benefit Plan Disclosure [Line Items]
Service cost	16	23	72	73
Interest cost	20	19	61	59
Expected return on assets	(30)	(27)	(94)	(85)
Amortization of:
Prior service cost (credit)	2	2	6	6
Actuarial loss (gain)	6	8	14	27
Net periodic benefit cost (credit)	14	25	59	80
Regulatory adjustments	63	52	58	36
Total expense recognized	77	77	117	116
Other postretirement benefits
Defined Benefit Plan Disclosure [Line Items]
Service cost	4	6	17	17
Interest cost	7	7	21	21
Expected return on assets	(16)	(14)	(48)	(44)
Amortization of:
Prior service cost (credit)	(1)	(1)	(2)	(2)
Actuarial loss (gain)	(4)	(3)	(11)	(7)
Settlement charges			0	0
Net periodic benefit cost (credit)	(10)	(5)	(23)	(15)
Regulatory adjustments	10	5	23	15
Total expense recognized	0	0	0	0
Other postretirement benefits | San Diego Gas and Electric Company
Defined Benefit Plan Disclosure [Line Items]
Service cost	1	2	4	4
Interest cost	1	1	4	4
Expected return on assets	(2)	(2)	(7)	(7)
Amortization of:
Actuarial loss (gain)	(1)	(1)	(2)	(2)
Net periodic benefit cost (credit)	(1)	0	(1)	(1)
Regulatory adjustments	1	0	1	1
Total expense recognized	0	0	0	0
Other postretirement benefits | Southern California Gas Company
Defined Benefit Plan Disclosure [Line Items]
Service cost	3	5	13	13
Interest cost	5	5	16	16
Expected return on assets	(13)	(12)	(40)	(36)
Amortization of:
Prior service cost (credit)	(1)	(1)	(2)	(2)
Actuarial loss (gain)	(3)	(2)	(9)	(5)
Net periodic benefit cost (credit)	(9)	(5)	(22)	(14)
Regulatory adjustments	9	5	22	14
Total expense recognized	$ 0	$ 0	$ 0	$ 0