FAIR VALUE MEASUREMENTS - RECON OF LEVEL 3 ASSETS (Details) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2022 USD ($) $ / MWh	Sep. 30, 2021 USD ($) $ / MWh	Sep. 30, 2022 USD ($) $ / MWh	Sep. 30, 2021 USD ($) $ / MWh
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Beginning balance	$ 33	$ 80	$ 54	$ 69
Realized and unrealized losses	(35)	(35)	(58)	(29)
Allocated transmission instruments	2	1	(4)	(1)
Settlements	33	26	41	33
Ending balance	33	72	33	72
Change in unrealized (losses) gains relating to instruments still held at September 30	3	9	(15)	5
Sempra Infrastructure
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	16	4	7	3
Realized and unrealized gains	2	3	16	8
Settlements	(2)	(2)	(7)	(6)
Ending balance	16	5	16	5
Change in unrealized gains (losses) relating to instruments still held at the end of the period	2	3	15	7
Sempra Infrastructure | Other current assets
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Ending balance	7		7
Sempra Infrastructure | Other long-term assets
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Ending balance	9		9
San Diego Gas and Electric Company
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Beginning balance	33	80	54	69
Realized and unrealized losses	(35)	(35)	(58)	(29)
Allocated transmission instruments	2	1	(4)	(1)
Settlements	33	26	41	33
Ending balance	33	72	33	72
Change in unrealized (losses) gains relating to instruments still held at September 30	$ 3	$ 9	$ (15)	$ 5
Level 3 | San Diego Gas and Electric Company | Minimum
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Congestion revenue rights (in dollars per MWH) | $ / MWh			(3.67)	(1.81)
Market electricity forward price inputs ( in dollars per MWH) | $ / MWh	26.75	24.05	26.75	24.05
Level 3 | San Diego Gas and Electric Company | Maximum
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Congestion revenue rights (in dollars per MWH) | $ / MWh			6.96	14.11
Market electricity forward price inputs ( in dollars per MWH) | $ / MWh	127.20	130.40	127.20	130.40
Level 3 | San Diego Gas and Electric Company | Weighted Average
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Congestion revenue rights (in dollars per MWH) | $ / MWh			(0.70)	(0.12)
Market electricity forward price inputs ( in dollars per MWH) | $ / MWh	68.50	57.36	68.50	57.36