Summary of Significant Accounting Policies (Cash) (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Restricted Cash and Cash Equivalents
Money market funds	$ 199	$ 784
Cash and cash equivalents	345	914
Short-term restricted cash	$ 35	$ 3
Restricted Cash, Current, Statement of Financial Position [Extensible Enumeration]	Other Assets, Current	Other Assets, Current
Long-term restricted cash	$ 152
Restricted Cash, Noncurrent, Statement of Financial Position [Extensible Enumeration]	Other Assets, Noncurrent	Other Assets, Noncurrent
Total cash, cash equivalents, and restricted cash	$ 532	$ 917	$ 394	$ 89
SCE
Restricted Cash and Cash Equivalents
Money market funds	78	647
Cash and cash equivalents	214	766
Short-term restricted cash	$ 33	$ 0
Restricted Cash, Current, Statement of Financial Position [Extensible Enumeration]	Other Assets, Current	Other Assets, Current
Long-term restricted cash	$ 151
Restricted Cash, Noncurrent, Statement of Financial Position [Extensible Enumeration]	Other Assets, Noncurrent	Other Assets, Noncurrent
Total cash, cash equivalents, and restricted cash	$ 398	$ 766	$ 280	$ 56