XML 223 R116.htm IDEA: XBRL DOCUMENT
v3.21.2

Commitments and Contingencies - Membership Interests of VIE Subject to Mandatory Redemption (Details) - USD ($) $ in Millions | Sep. 30, 2021 | Sep. 30, 2020
--- | --- | ---
Portion at Other than Fair Value Measurement [Member] |  |
Long-term Purchase Commitment [Line Items] |  |
Financial Instruments Subject to Mandatory Redemption, Settlement Terms, Share Value, Amount | $ 23 | $ 26
Financial Instruments Subject to Mandatory Redemption, Settlement Terms, Share Value, Amount | 30 | $ 35
Minimum payments on membership interests subject to mandatory redemption, due in next twelve months | 3 |
Minimum payments on membership interests subject to mandatory redemption, due in year two | 2 |
Minimum payments on membership interests subject to mandatory redemption, due in year three | 1 |
Minimum payments on membership interests subject to mandatory redemption, due in year four | 1 |
Minimum payments on membership interests subject to mandatory redemption, due in year five | $ 1 |

X
- Definition Minimum payments on membership interests subject to mandatory redemption, due in next twelve months + References No definition available. + Details
Name: | tve_Minimumpaymentsonmembershipinterestssubjecttomandatoryredemptiondueinnexttwelvemonths
Namespace Prefix: | tve_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Minimum payments on membership interests subject to mandatory redemption, due in year five + References No definition available. + Details
Name: | tve_Minimumpaymentsonmembershipinterestssubjecttomandatoryredemptiondueinyearfive
Namespace Prefix: | tve_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Minimum payments on membership interests subject to mandatory redemption, due in year four + References No definition available. + Details
Name: | tve_Minimumpaymentsonmembershipinterestssubjecttomandatoryredemptiondueinyearfour
Namespace Prefix: | tve_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Minimum payments on membership interests subject to mandatory redemption, due in year three + References No definition available. + Details
Name: | tve_Minimumpaymentsonmembershipinterestssubjecttomandatoryredemptiondueinyearthree
Namespace Prefix: | tve_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Minimum payments on membership interests subject to mandatory redemption, due in year two + References No definition available. + Details
Name: | tve_Minimumpaymentsonmembershipinterestssubjecttomandatoryredemptiondueinyeartwo
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_LongTermPurchaseCommitmentLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount that would be paid, determined under the conditions specified in the contract, if the holder of the share has the right to redeem the shares. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 480 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=109262807&loc=d3e22047-110879 + Details
Name: | us-gaap_SharesSubjectToMandatoryRedemptionSettlementTermsAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Details
Name: | us-gaap_FairValueByMeasurementBasisAxis=us-gaap_PortionAtOtherThanFairValueFairValueDisclosureMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |