FAIR VALUE MEASUREMENTS - RECON OF LEVEL 3 ASSETS (Details) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024 USD ($)	Sep. 30, 2023 USD ($)	Sep. 30, 2024 USD ($) $ / MWh	Sep. 30, 2023 USD ($) $ / MWh
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Beginning balance	$ 6	$ 20	$ 10	$ 35
Realized and unrealized gains (losses), net	(3)	(2)	(6)	(10)
Allocated transmission instruments	1	1	1	(1)
Settlements	2	(1)	1	(6)
Ending balance	6	18	6	18
Change in unrealized gains relating to instruments still held at September 30	0	1	(1)	(8)
Other Sempra
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	23	23	23	17
Realized and unrealized gains (losses), net	3	(3)	7	7
Settlements	(2)	(2)	(6)	(6)
Ending balance	24	18	24	18
Change in unrealized gains (losses) relating to instruments still held at September 30	3	(2)	6	7
Other Sempra | Other current assets
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Ending balance	7		7
Other Sempra | Other long-term assets
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Ending balance	17		17
SDG&E
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Beginning balance	6	20	10	35
Realized and unrealized gains (losses), net	(3)	(2)	(6)	(10)
Allocated transmission instruments	1	1	1	(1)
Settlements	2	(1)	1	(6)
Ending balance	6	18	6	18
Change in unrealized gains relating to instruments still held at September 30	$ 0	$ 1	$ (1)	$ (8)
Level 3 | SDG&E | Minimum
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Congestion revenue rights (in dollars per MWH) | $ / MWh			(3.69)	(3.09)
Level 3 | SDG&E | Maximum
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Congestion revenue rights (in dollars per MWH) | $ / MWh			9.55	10.71
Level 3 | SDG&E | 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			(0.44)	(0.56)