Regulatory Assets and Liabilities (Schedule of Regulatory Assets) (Details) - USD ($) $ in Millions	Jun. 30, 2016	Dec. 31, 2015
Regulatory Assets [Line Items]
Regulatory assets	$ 478	$ 560
Regulatory assets	7,792	7,512
Environmental remediation
Regulatory Assets [Line Items]
Regulatory assets	128	129
Southern California Edison
Regulatory Assets [Line Items]
Regulatory assets	478	560
Regulatory assets	7,792	7,512
Total regulatory assets	8,270	8,072
Southern California Edison \| Regulatory balancing accounts
Regulatory Assets [Line Items]
Regulatory assets	309	382
Regulatory assets	49	36
Southern California Edison \| Energy derivatives
Regulatory Assets [Line Items]
Regulatory assets	135	159
Regulatory assets	1,041	1,027
Southern California Edison \| Other
Regulatory Assets [Line Items]
Regulatory assets	34	19
Regulatory assets	271	288
Southern California Edison \| Deferred income taxes, net
Regulatory Assets [Line Items]
Regulatory assets	4,176	3,757
Southern California Edison \| Pensions and other postretirement benefits
Regulatory Assets [Line Items]
Regulatory assets	836	849
Southern California Edison \| Unamortized investments, net
Regulatory Assets [Line Items]
Regulatory assets	156	182
Southern California Edison \| San Onofre
Regulatory Assets [Line Items]
Regulatory assets	942	1,043
Southern California Edison \| Unamortized loss on reacquired debt
Regulatory Assets [Line Items]
Regulatory assets	$ 193	$ 201

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+ 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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