SAN ONOFRE NUCLEAR GENERATING STATION - NUCLEAR DECOMMISSIONING TRUSTS (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022
Debt Securities, Available-for-sale [Line Items]
Cost	$ 683		$ 689
Gross unrealized gains	214		196
Gross unrealized losses	(33)		(44)
Estimated fair value	864		841
Proceeds from sales	156	$ 242
Gross realized gains	2	11
Gross realized losses	(3)	$ (4)
Total debt securities
Debt Securities, Available-for-sale [Line Items]
Cost	556		571
Gross unrealized gains	5		2
Gross unrealized losses	(28)		(36)
Estimated fair value	533		537
U.S. government corporations and agencies
Debt Securities, Available-for-sale [Line Items]
Cost	37		40
Gross unrealized gains	1		1
Gross unrealized losses	(1)		(1)
Estimated fair value	37		40
Municipal bonds
Debt Securities, Available-for-sale [Line Items]
Cost	274		283
Gross unrealized gains	2		1
Gross unrealized losses	(10)		(14)
Estimated fair value	266		270
Other securities
Debt Securities, Available-for-sale [Line Items]
Cost	245		248
Gross unrealized gains	2		0
Gross unrealized losses	(17)		(21)
Estimated fair value	230		227
Equity securities
Debt Securities, Available-for-sale [Line Items]
Cost	112		111
Gross unrealized gains	209		194
Gross unrealized losses	(5)		(8)
Estimated fair value	316		297
Short-term investments, primarily cash equivalents
Debt Securities, Available-for-sale [Line Items]
Cost	19		11
Gross unrealized gains	0		0
Gross unrealized losses	0		0
Estimated fair value	19		11
Receivables (payables), net
Debt Securities, Available-for-sale [Line Items]
Cost	(4)		(4)
Gross unrealized gains	0		0
Gross unrealized losses	0		0
Estimated fair value	$ (4)		$ (4)