Regulatory Assets and Liabilities (Details) - USD ($) $ in Millions	Mar. 31, 2016	Dec. 31, 2015
Regulatory Assets
Regulatory Assets, Current	$ 538	$ 560
Regulatory Asset, Long-term	7,628	7,512
Regulatory Liabilities
Regulatory Liabilities, Current	1,157	1,128
Regulatory Liabilities, Long-term	5,920	5,676
Environmental Restoration Costs
Regulatory Assets
Regulatory Asset, Long-term	131	129
Southern California Edison
Regulatory Assets
Regulatory Assets, Current	538	560
Regulatory Asset, Long-term	7,628	7,512
Total Regulatory Assets	8,166	8,072
Regulatory Liabilities
Regulatory Liabilities, Current	1,157	1,128
Regulatory Liabilities, Long-term	5,920	5,676
Total Regulatory Liabilities	7,077	6,804
Southern California Edison \| Regulatory balancing accounts
Regulatory Assets
Regulatory Assets, Current	329	382
Regulatory Asset, Long-term	39	36
Southern California Edison \| Energy derivatives
Regulatory Assets
Regulatory Assets, Current	182	159
Regulatory Asset, Long-term	1,066	1,027
Southern California Edison \| Other
Regulatory Assets
Regulatory Assets, Current	27	19
Regulatory Asset, Long-term	282	288
Regulatory Liabilities
Regulatory Liabilities, Current	22	22
Regulatory Liabilities, Long-term	56	79
Southern California Edison \| Deferred income taxes, net
Regulatory Assets
Regulatory Asset, Long-term	3,920	3,757
Southern California Edison \| Pensions and other postretirement benefits
Regulatory Assets
Regulatory Asset, Long-term	842	849
Southern California Edison \| Unamortized investments, net
Regulatory Assets
Regulatory Asset, Long-term	169	182
Southern California Edison \| San Onofre
Regulatory Assets
Regulatory Asset, Long-term	982	1,043
Southern California Edison \| Unamortized loss on reacquired debt
Regulatory Assets
Regulatory Asset, Long-term	197	201
Southern California Edison \| Regulatory balancing accounts
Regulatory Liabilities
Regulatory Liabilities, Current	1,135	1,106
Regulatory Liabilities, Long-term	1,352	1,314
Southern California Edison \| Costs of removal
Regulatory Liabilities
Regulatory Liabilities, Long-term	2,822	2,781
Southern California Edison \| Recoveries in excess of ARO liabilities
Regulatory Liabilities
Regulatory Liabilities, Long-term	$ 1,690	$ 1,502

-- None. No documentation exists for this element. --

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- Definition

-- None. No documentation exists for this element. --

+ References

No definition available.

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- Definition

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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- Definition

Carrying amount as of the balance sheet date of capitalized costs of regulated entities that are expected to be recovered through revenue sources within one year or the normal operating cycle, if longer. Such costs are capitalized if they meet both of the following criteria: a. It is probable that future revenue in an amount at least equal to the capitalized cost will result from inclusion of that cost in allowable costs for rate-making purposes. b. Based on available evidence, the future revenue will be provided to permit recovery of the previously incurred cost rather than to provide for expected levels of similar future costs. If the revenue will be provided through an automatic rate-adjustment clause, this criterion requires that the regulator's intent clearly be to permit recovery of the previously incurred cost.

+ References

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- Definition

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.

+ References

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- Definition

The amount for the individual regulatory liability as itemized in a table of regulatory liabilities 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 405
-Section 25
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6500807&loc=d3e48068-110394

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- Definition

The amount for the individual regulatory current liability as itemized in a table of regulatory current liabilities as of the end of the period.

+ References

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- Definition

The amount for the individual regulatory noncurrent liability as itemized in a table of regulatory noncurrent liabilities as of the end of the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.24)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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