Summary of Significant Accounting Policies (Organization (Details)	3 Months Ended
Mar. 31, 2021 mi²
SCE
Segment Reporting Information [Line Items]
Supply of electricity area covered (in square miles)	50,000

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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Period Type:	duration