Summary of Significant Accounting Policies (Cash) (Details) - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Restricted Cash and Cash Equivalents Items [Line Items]
Money market funds	$ 784	$ 329
Cash and cash equivalents	914	390
Short-term restricted cash	$ 3	$ 4
Restricted Cash, Current, Statement of Financial Position [Extensible Enumeration]	Other Assets, Current	Other Assets, Current
Total cash, cash equivalents, and restricted cash	$ 917	$ 394	$ 89	$ 70
SCE
Restricted Cash and Cash Equivalents Items [Line Items]
Money market funds	647	230
Cash and cash equivalents	766	279
Short-term restricted cash	$ 0	$ 1
Restricted Cash, Current, Statement of Financial Position [Extensible Enumeration]	Other Assets, Current	Other Assets, Current
Total cash, cash equivalents, and restricted cash	$ 766	$ 280	$ 56	$ 24