Revenue (Textual) (Details) - SCE - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Public Utilities, General Disclosures [Line Items]
Franchise fees billed to customers	$ 133	$ 133	$ 111
Rate recovery period	24 months

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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