Summary of Significant Accounting Policies (Cash) (Details) - USD ($) $ in Millions	Jun. 30, 2023	Dec. 31, 2022	Jun. 30, 2022	Dec. 31, 2021
Restricted Cash and Cash Equivalents Items [Line Items]
Money market funds	$ 123	$ 784
Cash and cash equivalents	195	914
Short-term restricted cash	$ 3	$ 3
Restricted Cash, Current, Statement of Financial Position [Extensible Enumeration]	Other Assets, Current	Other Assets, Current
Total cash, cash equivalents, and restricted cash	$ 198	$ 917	$ 123	$ 394
SCE
Restricted Cash and Cash Equivalents Items [Line Items]
Money market funds	5	647
Cash and cash equivalents	68	766
Total cash, cash equivalents, and restricted cash	$ 68	$ 766	$ 67	$ 280