XML 179 R91.htm IDEA: XBRL DOCUMENT
v3.22.2.2

Fair Value Measurements - Fair Value Measurements Using Significant Unobservable Inputs (Details) - USD ($) $ in Millions | Sep. 30, 2022 | Sep. 30, 2021
--- | --- | ---
Fair Value Measurements |  |
Commodity contract derivatives, assets | $ 152 | $ 250
Commodity contract derivatives, liabilities | 7 | 3
Fair Value, Inputs, Level 3 |  |
Fair Value Measurements |  |
Commodity contract derivatives, assets | 0 | 0
Commodity contract derivatives, liabilities | $ 0 | $ 0

X
- Definition The fair value as of the balance sheet date of firm obligations in physical commodity contracts (for example, agricultural products, metals and energy). + References No definition available. + Details
Name: | tve_Commoditycontractderivativeliabilitiesfairvaluedisclosure
Namespace Prefix: | tve_
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_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The fair value as of the balance sheet date of firm holdings in physical commodity contracts (for example, agricultural products, metals and energy). Includes both pledged (to counterparties as collateral for financing transactions) and unpledged holdings. + References No definition available. + Details
Name: | us-gaap_FinancialInstrumentsOwnedPhysicalCommoditiesAtFairValue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueInputsLevel3Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |