XML 99 R78.htm IDEA: XBRL DOCUMENT
v3.22.0.1

Contingencies and Legal Proceedings Contingencies (Details) $ in Millions | 3 Months Ended |
--- | --- | ---
Dec. 31, 2021 USD ($) Insurance_layers reactors Procedures | Sep. 30, 2021 USD ($)
Loss Contingencies |  |
Nuclear liability insurance | $ 450 |
Assessment from licensees for each licensed reactor | $ 138 |
Number of licensed reactors in US | reactors | 95 |
Nuclear accident assessment limitation per year per unit | $ 20 |
Maximum assessment per nuclear incident | 963 |
Total amount of protection available | 13,500 |
Amount of insurance available for loss at any one site | 2,100 |
Maximum amount of retrospective premiums | 128 |
Maximum idemnity if a covered accident takes or keeps a nuclear unit offline | 490 |
Maximum retrospective premiums | 43 |
Estimated future decommissioning cost | $ 7,159 | $ 7,002
Number of procedures for determining estimates for the costs of nuclear decommissioning | Procedures | 2 |
Possible additional future costs for compliance with Clean Air Act requirements | $ 151 |
Possible additional future costs for compliance with CCR requirements | 720 |
Possible additional future costs for compliance with Clean Water requirements. | 145 |
Estimated liability for cleanup and environmental work |  | 18
Amount of insurance available for loss at any one site (top range) | 2,800 |
Long-term debt of VIEs, net (including current maturities) | $ 1,292 | 1,307
The U.S. Congress is required to take action if these layes are exhausted | Insurance_layers | 2 |
Nuclear |  |
Loss Contingencies |  |
Estimated future decommissioning cost | $ 3,466 | 3,428
Non-nuclear |  |
Loss Contingencies |  |
Estimated future decommissioning cost | 3,693 | $ 3,574
Environmental Agreements |  |
Loss Contingencies |  |
Amount invested in certain environmental projects | 281 |
General |  |
Loss Contingencies |  |
Legal loss contingency accrual | $ 12 |

X
- Definition Amount invested in certain environmental projects + References No definition available. + Details
Name: | tve_AmountInvestedInCertainEnvironmentalProjects
Namespace Prefix: | tve_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The amount of property, decommissioning, and decontamination insurance available for loss at any one site to cover the cost of stabilizing or shutting down a reactor after an accident. + References No definition available. + Details
Name: | tve_AmountOfInsuranceAvailableForLossAtAnyOneSiteBottomRange
Namespace Prefix: | tve_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of insurance available for loss at any one site (top range) + References No definition available. + Details
Name: | tve_AmountOfInsuranceAvailableForLossAtAnyOneSiteTopRange
Namespace Prefix: | tve_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition An assessment from licensees for each licensed nuclear reactor in the United States to fund the second layer, the Secondary Financial Program. + References No definition available. + Details
Name: | tve_AssessmentFromLicenseesForEachLicensedReactor
Namespace Prefix: | tve_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Maximum assessment per nuclear incident. + References No definition available. + Details
Name: | tve_MaximumAssessmentPerNuclearIncident
Namespace Prefix: | tve_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The maximum idemnity per unit if an accident covered by the policy tasks or keeps a nuclear unit offline. + References No definition available. + Details
Name: | tve_MaximumIdemnityIfCoveredAccidentTasksOrKeepsNuclearUnitOffline
Namespace Prefix: | tve_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The maximum amount of retrospective premiums that may be required for property, decommissioning, and decontamination insurance. + References No definition available. + Details
Name: | tve_Maximumamountofretrospectivepremiums
Namespace Prefix: | tve_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition The per year per unit limitation of the assessment for any nuclear accident + References No definition available. + Details
Name: | tve_NuclearAccidentAssessmentLimitationPerYearPerUnit
Namespace Prefix: | tve_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition For the first layer of protection all NRC nuclear plant licensees purchase nuclear insurance from American Nuclear Insurers for each nuclear plant with an operating license. + References No definition available. + Details
Name: | tve_NuclearLiabilityInsurance
Namespace Prefix: | tve_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Number of procedures for determining estimates for the costs of nuclear decommissioning + References No definition available. + Details
Name: | tve_NumberOfProceduresForDeterminingEstimatesForCostsOfNuclearDecommissioning
Namespace Prefix: | tve_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Definition The number of licensed reactors in US. + References No definition available. + Details
Name: | tve_NumberoflicensedreactorsinUS
Namespace Prefix: | tve_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition The possible additional future costs for compliance with Clean Air Act requirements. + References No definition available. + Details
Name: | tve_PossibleAdditionalFutureCostsForComplianceWithCleanAirActRequirements
Namespace Prefix: | tve_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The possible additional future costs for compliance with CCR requirements + References No definition available. + Details
Name: | tve_PossibleadditionalfuturecostsforcompliancewithCCRrequirements
Namespace Prefix: | tve_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition The possible additional future costs for compliance with Clean Water requirements. + References No definition available. + Details
Name: | tve_PossibleadditionalfuturecostsforcompliancewithCleanWaterrequirements.
Namespace Prefix: | tve_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition The maximum amount of retrospective premiums that could be required for accidental outage insurance. + References No definition available. + Details
Name: | tve_RetrospectivePremiums
Namespace Prefix: | tve_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition The total amount of protection available to compensate for losses arising from a nuclear event in the United States. + References No definition available. + Details
Name: | tve_TotalAmountOfProtectionAvailable
Namespace Prefix: | tve_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition The U.S. Congress is required to take action to provide additional funds to cover the additional losses if these layes are exhausted. + References No definition available. + Details
Name: | tve_USCongressIsRequiredToTakeActionIfTheseLayesAreExhausted
Namespace Prefix: | tve_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Definition Undiscounted amount of the accrual for environmental loss contingencies. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 410 -SubTopic 30 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=6393242&loc=d3e13207-110859 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 5.Y.Q1) -URI http://asc.fasb.org/extlink&oid=27011672&loc=d3e149879-122751 + Details
Name: | us-gaap_AccrualForEnvironmentalLossContingenciesGross
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition 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_AssetRetirementObligation
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition 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. + References No definition available. + Details
Name: | us-gaap_LossContingenciesLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of loss contingency liability. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=121557415&loc=d3e14326-108349 + Details
Name: | us-gaap_LossContingencyAccrualAtCarryingValue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of long-term debt classified as other. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(16)) -URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(16)) -URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878 + Details
Name: | us-gaap_OtherLongTermDebt
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Details
Name: | tve_ReconciliationOfAssetRetirementObligationLiabilityAxis=tve_NuclearMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | tve_ReconciliationOfAssetRetirementObligationLiabilityAxis=tve_NonNuclearMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_LitigationCaseAxis=tve_EnvironmentalAgreementsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_LitigationCaseAxis=tve_GeneralMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |