Regulatory Assets and Liabilities (Assets) (Details) - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
Regulatory Assets [Line Items]
Current regulatory assets	$ 1,578	$ 1,314
Regulatory assets: Non-current	7,543	7,120
SCE
Regulatory Assets [Line Items]
Current regulatory assets	1,578	1,314
Regulatory assets: Non-current	7,543	7,120
Total regulatory assets	9,121	8,434
SCE \| Regulatory balancing and memorandum accounts
Regulatory Assets [Line Items]
Current regulatory assets	1,390	1,127
Regulatory assets: Non-current	1,815	1,794
SCE \| Power contracts
Regulatory Assets [Line Items]
Current regulatory assets	166	165
Regulatory assets: Non-current	221	239
SCE \| Other regulatory assets or liabilities
Regulatory Assets [Line Items]
Current regulatory assets	22	22
Regulatory assets: Non-current	135	106
SCE \| Deferred income taxes, net of liabilities
Regulatory Assets [Line Items]
Regulatory assets: Non-current	4,526	4,475
SCE \| Pension and other postretirement benefits
Regulatory Assets [Line Items]
Regulatory assets: Non-current	8	12
SCE \| Unamortized investments, net of accumulated amortization
Regulatory Assets [Line Items]
Regulatory assets: Non-current	112	114
SCE \| Unamortized loss on reacquired debt
Regulatory Assets [Line Items]
Regulatory assets: Non-current	130	133
SCE \| Environmental remediation
Regulatory Assets [Line Items]
Regulatory assets: Non-current	265	$ 247
SCE \| Recoverable assets
Regulatory Assets [Line Items]
Regulatory assets: Non-current	$ 331

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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://fasb.org/us-gaap/role/ref/legacyRef
-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.

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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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