Related-Party Transactions (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Related Party Transaction [Line Items]
Wildfire Insurance Fund expense	$ 84	$ 0
Southern California Edison
Related Party Transaction [Line Items]
Wildfire Insurance Fund expense	84	0
Southern California Edison \| Subsidiary of Common Parent \| Wildfire Liability Insurance
Related Party Transaction [Line Items]
Wildfire insurance premiums		186
Long-term insurance receivable due from affiliate	803		$ 803
Prepaid insurance	32		$ 10
Wildfire Insurance Fund expense	$ 50	$ 31

Amount of receivables due from an entity that is affiliated with the reporting entity by means of direct or indirect ownership, due after 1 year (or 1 business cycle).

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+ Details