Revenue (Receivables, Accrued Unbilled Revenue and Contract Liabilities) (Details) - USD ($) $ in Millions	Jun. 30, 2018	Dec. 31, 2017
Receivables:
Billed revenue	$ 693	$ 613
Accrued unbilled revenues	598	212
Total receivables	1,291	825
Southern California Edison
Receivables:
Contract liabilities	$ 20	$ 20

For an unclassified balance sheet, the amount due from customers or clients for goods or services that have been delivered or sold in the normal course of business, reduced to their estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.

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Amounts due for billed services rendered or to be rendered, actions taken or to be taken, or a promise to refrain from taking certain actions in accordance with the terms of a legally binding agreement between the Company and, at a minimum, one other party. An example would be amounts billed to customers under contracts or programs but not paid as of the balance sheet date.

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Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable.

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Unbilled amounts due for services rendered or to be rendered, actions taken or to be taken, or a promise to refrain from taking certain actions in accordance with the terms of a legally binding agreement between the entity and, at a minimum, one other party. An example would be amounts associated with contracts or programs where the recognized revenue for performance thereunder exceeds the amounts billed under the terms thereof as of the date of the balance sheet.

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