XML 135 R65.htm IDEA: XBRL DOCUMENT
v3.24.3

Summary of Significant Accounting Policies - Pre-commercial Plant Ops (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Sep. 30, 2024 | Sep. 30, 2023 | Sep. 30, 2022
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |
Revenue capitalized during pre-commercial operations | $ 3 | $ 3 | $ 0
Fuel capitalized during pre-commercial ops | $ 3 |  |

X
- Definition Pre-commercial Ops - Capitalized Fuel + References No definition available. + Details
Name: | tve_PreCommercialOpsCapitalizedFuel
Namespace Prefix: | tve_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Pre-commercial Ops - Capitalized Revenue + References No definition available. + Details
Name: | tve_PreCommercialOpsCapitalizedRevenue
Namespace Prefix: | tve_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

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_RevenuesFromExternalCustomersAndLongLivedAssetsLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration