SAN ONOFRE NUCLEAR GENERATING STATION - NUCLEAR DECOMMISSIONING TRUSTS (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022	Dec. 31, 2022
Debt Securities, Available-for-sale [Line Items]
Cost	$ 673		$ 673		$ 689
Gross unrealized gains	224		224		196
Gross unrealized losses	(34)		(34)		(44)
Estimated fair value	863		863		841
Proceeds from sales	138	$ 155	294	$ 397
Gross realized gains	6	3	8	14
Gross realized losses	(3)	$ (7)	(6)	$ (11)
Total debt securities
Debt Securities, Available-for-sale [Line Items]
Cost	551		551		571
Gross unrealized gains	2		2		2
Gross unrealized losses	(30)		(30)		(36)
Estimated fair value	523		523		537
U.S. government corporations and agencies
Debt Securities, Available-for-sale [Line Items]
Cost	40		40		40
Gross unrealized gains	1		1		1
Gross unrealized losses	(2)		(2)		(1)
Estimated fair value	39		39		40
Municipal bonds
Debt Securities, Available-for-sale [Line Items]
Cost	277		277		283
Gross unrealized gains	1		1		1
Gross unrealized losses	(12)		(12)		(14)
Estimated fair value	266		266		270
Other securities
Debt Securities, Available-for-sale [Line Items]
Cost	234		234		248
Gross unrealized gains	0		0		0
Gross unrealized losses	(16)		(16)		(21)
Estimated fair value	218		218		227
Equity securities
Debt Securities, Available-for-sale [Line Items]
Cost	104		104		111
Gross unrealized gains	222		222		194
Gross unrealized losses	(4)		(4)		(8)
Estimated fair value	322		322		297
Short-term investments, primarily cash equivalents
Debt Securities, Available-for-sale [Line Items]
Cost	24		24		11
Gross unrealized gains	0		0		0
Gross unrealized losses	0		0		0
Estimated fair value	24		24		11
Receivables (payables), net
Debt Securities, Available-for-sale [Line Items]
Cost	(6)		(6)		(4)
Gross unrealized gains	0		0		0
Gross unrealized losses	0		0		0
Estimated fair value	$ (6)		$ (6)		$ (4)