Regulatory Assets and Liabilities (Schedule of Regulatory Assets) (Details) - USD ($) $ in Millions	Sep. 30, 2016	Dec. 31, 2015
Regulatory Assets [Line Items]
Current regulatory assets	$ 321	$ 560
Long-term regulatory assets	7,844	7,512
Environmental remediation
Regulatory Assets [Line Items]
Long-term regulatory assets	128	129
Southern California Edison
Regulatory Assets [Line Items]
Current regulatory assets	321	560
Long-term regulatory assets	7,844	7,512
Total regulatory assets	8,165	8,072
Southern California Edison \| Regulatory balancing accounts
Regulatory Assets [Line Items]
Current regulatory assets	135	382
Long-term regulatory assets	36	36
Southern California Edison \| Energy derivatives
Regulatory Assets [Line Items]
Current regulatory assets	167	159
Long-term regulatory assets	1,010	1,027
Southern California Edison \| Other
Regulatory Assets [Line Items]
Current regulatory assets	19	19
Long-term regulatory assets	264	288
Southern California Edison \| Deferred income taxes, net
Regulatory Assets [Line Items]
Long-term regulatory assets	4,346	3,757
Southern California Edison \| Pensions and other postretirement benefits
Regulatory Assets [Line Items]
Long-term regulatory assets	829	849
Southern California Edison \| Unamortized investments, net
Regulatory Assets [Line Items]
Long-term regulatory assets	143	182
Southern California Edison \| San Onofre
Regulatory Assets [Line Items]
Long-term regulatory assets	899	1,043
Southern California Edison \| Unamortized loss on reacquired debt
Regulatory Assets [Line Items]
Long-term regulatory assets	$ 189	$ 201

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The amount for the individual regulatory asset as itemized in a table of regulatory assets as of the end of the period.

+ References

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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