Related-Party Transactions (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Related Party Transaction [Line Items]
Wildfire Insurance Fund expense	$ 336	$ 152	$ 0
SCE
Related Party Transaction [Line Items]
Current insurance receivable due from affiliate	268	0
Wildfire Insurance Fund expense	336	152	0
SCE \| Wildfire liability insurance \| Wholly-owned subsidiary
Related Party Transaction [Line Items]
Wildfire insurance premiums	176	260	22
Current insurance receivable due from affiliate	268	0
Long-term insurance receivables due from affiliate	0	803
Prepaid Insurance	56	10
Wildfire Insurance Fund expense	$ 189	$ 173	$ 140

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