XML 76 R59.htm IDEA: XBRL DOCUMENT
v3.20.4

Summary of Significant Accounting Policies (Nuclear Decommissioning and Asset Retirement Obligations) (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019
Asset Retirement Obligation, Roll Forward |  |
Beginning balance | $ 3,029 |
Ending balance | 2,930 | $ 3,029
SCE |  |
Asset Retirement Obligation, Roll Forward |  |
Beginning balance | 3,029 | 3,031
Accretion | 160 | 166
Revisions | (36) | 4
Liabilities settled | (223) | (172)
Ending balance | 2,930 | $ 3,029
SCE | Palo Verde and San Onofre Units |  |
Asset Retirement Obligation, Roll Forward |  |
Recorded liability to decommission nuclear power facilities | 2,600 |
Estimated cost to decommission nuclear facilities | $ 6,600 |
Decommissioning cost escalated rates, low end (percent) | 0.60% |
Decommissioning cost escalated rates, high end (as a percent) | 7.50% |
Estimated annual net of tax earnings, low end (as a percent) | 1.30% |
Estimated annual net of tax earnings, high end (as a percent) | 4.10% |

X
- Definition This element represents the asset retirement obligation for decommissioning active and inactive nuclear facilities at the balance sheet date. + References No definition available. + Details
Name: | eix_DecommissioningActiveAndInactiveNuclearFacilitiesAssetRetirementObligation
Namespace Prefix: | eix_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition This element represents the high end of the range of the escalated rates under decommissioning cost methodology used for rate-making purpose. + References No definition available. + Details
Name: | eix_DecommissioningCostEscalatedRatesHighEndOfRange
Namespace Prefix: | eix_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition This element represents the low end of the range of the escalated rates under decommissioning cost methodology used for rate-making purpose. + References No definition available. + Details
Name: | eix_DecommissioningCostEscalatedRatesLowEndOfRange
Namespace Prefix: | eix_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition This element represents the total estimated cost to decommission its active nuclear facilities. + References No definition available. + Details
Name: | eix_DecommissioningEstimatedCost
Namespace Prefix: | eix_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition This element represents the high end of the range of the estimated annual after-tax earnings on the decommissioning funds. + References No definition available. + Details
Name: | eix_DecommissioningFundsEstimatedAnnualEarningsNetOfTaxPercentageHighEndOfRange
Namespace Prefix: | eix_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition This element represents the low end of the range of the estimated annual after-tax earnings on the decommissioning funds. + References No definition available. + Details
Name: | eix_DecommissioningFundsEstimatedAnnualEarningsNetOfTaxPercentageLowEndOfRange
Namespace Prefix: | eix_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of accretion expense recognized during the period that is associated with an asset retirement obligation. Accretion expense measures and incorporates changes due to the passage of time into the carrying amount of the liability. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 410 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c)(3) -URI http://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 410 -SubTopic 20 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6392676&loc=d3e7480-110848 + Details
Name: | us-gaap_AssetRetirementObligationAccretionExpense
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of asset retirement obligations settled, or otherwise disposed of, during the period. This may include asset retirement obligations transferred to third parties associated with the sale of a long-lived asset. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 410 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849 + Details
Name: | us-gaap_AssetRetirementObligationLiabilitiesSettled
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of increase (decrease) in the asset retirement obligation from changes in the amount or timing of the estimated cash flows associated with the settlement of the obligation. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 410 -SubTopic 20 -Section 35 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=6392603&loc=d3e7123-110846 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 410 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c)(4) -URI http://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849 + Details
Name: | us-gaap_AssetRetirementObligationRevisionOfEstimate
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. + References No definition available. + Details
Name: | us-gaap_AssetRetirementObligationRollForwardAnalysisRollForward
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Noncurrent portion of the carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 410 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849 + Details
Name: | us-gaap_AssetRetirementObligationsNoncurrent
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Details
Name: | dei_LegalEntityAxis=eix_SouthernCaliforniaEdisonCompanyMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_JointlyOwnedUtilityPlantAxis=eix_PaloVerdeSanOnofre12and3Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |