XML 112 R56.htm IDEA: XBRL DOCUMENT
v3.25.3

Commitments and Contingencies (Tables) | 12 Months Ended
--- | ---
Sep. 30, 2025
Commitments and Contingencies Disclosure [Abstract] |
Unfunded loan commitments | At September 30, 2025, TVA had no commitments under unfunded loan commitments for 2026 through 2030.

X
- Definition Unfunded loan commitments [Table Text Block] + References No definition available. + Details
Name: | tve_UnfundedloancommitmentsTableTextBlock
Namespace Prefix: | tve_
Data Type: | dtr-types:textBlockItemType
Balance Type: | na
Period Type: | duration

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