SAN ONOFRE NUCLEAR GENERATING STATION - NUCLEAR DECOMMISSIONING TRUSTS (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023
Debt Securities, Available-for-sale [Line Items]
Cost	$ 671		$ 671		$ 661
Gross unrealized gains	249		249		233
Gross unrealized losses	(14)		(14)		(22)
Estimated fair value	906		906		872
Proceeds from sales	259	$ 143	639	$ 437
Gross realized gains	17	12	41	20
Gross realized losses	2	$ 3	7	$ 9
Short-term investments, primarily cash equivalents
Debt Securities, Available-for-sale [Line Items]
Cost	18		18		21
Gross unrealized gains	0		0		0
Gross unrealized losses	0		0		0
Estimated fair value	18		18		21
Equity securities
Debt Securities, Available-for-sale [Line Items]
Cost	80		80		89
Gross unrealized gains	241		241		225
Gross unrealized losses	(2)		(2)		(2)
Estimated fair value	319		319		312
Total debt securities
Debt Securities, Available-for-sale [Line Items]
Cost	592		592		558
Gross unrealized gains	8		8		8
Gross unrealized losses	(12)		(12)		(20)
Estimated fair value	588		588		546
Debt securities issued by the U.S. Treasury and other U.S. government corporations and agencies
Debt Securities, Available-for-sale [Line Items]
Cost	69		69		50
Gross unrealized gains	1		1		2
Gross unrealized losses	0		0		(1)
Estimated fair value	70		70		51
Municipal bonds
Debt Securities, Available-for-sale [Line Items]
Cost	290		290		280
Gross unrealized gains	3		3		3
Gross unrealized losses	(6)		(6)		(8)
Estimated fair value	287		287		275
Other securities
Debt Securities, Available-for-sale [Line Items]
Cost	233		233		228
Gross unrealized gains	4		4		3
Gross unrealized losses	(6)		(6)		(11)
Estimated fair value	231		231		220
Receivables (payables), net
Debt Securities, Available-for-sale [Line Items]
Cost	(19)		(19)		(7)
Gross unrealized gains	0		0		0
Gross unrealized losses	0		0		0
Estimated fair value	$ (19)		$ (19)		$ (7)