Commitments and Contingencies (San Onofre CPUC Proceedings) (Details) - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015
Regulatory Assets [Line Items]
Regulatory assets	$ 7,455	$ 7,512
SCE
Regulatory Assets [Line Items]
Regulatory assets	7,455	7,512
San Onofre \| SCE
Regulatory Assets [Line Items]
Regulatory assets	$ 857	$ 1,043

Carrying amount as of the balance sheet date of capitalized costs of regulated entities that are not expected to be recovered through revenue sources within one year or the normal operating cycle if longer.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 980
-SubTopic 340
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6499975&loc=d3e44250-110382

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant