FAIR VALUE MEASUREMENTS - RECON OF LEVEL 3 ASSETS (Details) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2025 USD ($)	Sep. 30, 2024 USD ($)	Sep. 30, 2025 USD ($) $ / MWh	Sep. 30, 2024 USD ($) $ / MWh
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Beginning balance	$ 3	$ 6	$ 4	$ 10
Realized and unrealized gains (losses), net	3	(3)	1	(6)
Allocated transmission instruments	2	1	5	1
Settlements	(2)	2	(4)	1
Ending balance	6	6	6	6
Change in unrealized gains (losses) relating to instruments still held at September 30	2	0	(1)	(1)
Other Sempra
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	39	23	25	23
Realized and unrealized gains (losses), net	2	3	20	7
Settlements	(2)	(2)	(6)	(6)
Ending balance	39	24	39	24
Change in unrealized gains (losses) relating to instruments still held at September 30	2	3	20	6
Other Sempra | Other current assets
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Ending balance	8		8
Other Sempra | Other long-term assets
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Ending balance	31		31
SDG&E
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Beginning balance	3	6	4	10
Realized and unrealized gains (losses), net	3	(3)	1	(6)
Allocated transmission instruments	2	1	5	1
Settlements	(2)	2	(4)	1
Ending balance	6	6	6	6
Change in unrealized gains (losses) relating to instruments still held at September 30	$ 2	$ 0	$ (1)	$ (1)
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			(7.38)	(3.69)
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			15.54	9.55
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			0.01	(0.44)