XML 120 R34.htm IDEA: XBRL DOCUMENT
v3.20.2

Proprietary Capital Payments to the U.S. Treasury (Policies) | 12 Months Ended
--- | ---
Sep. 30, 2020
Equity [Abstract] |
Payments to U S Treasury | Payments to the U.S. Treasury TVA paid the U.S. Treasury $6 million, $6 million, and $5 million in 2020, 2019, and 2018, respectively, as a return on the Power Program Appropriation Investment. The amount of the return on the Power Program Appropriation Investment is based on the Power Program Appropriation Investment balance at the beginning of that year and the computed average interest rate payable by the U.S. Treasury on its total marketable public obligations at the same date. The interest rates payable by TVA on the Power Program Appropriation Investment were 2.44 percent, 2.37 percent, and 2.09 percent for 2020, 2019, and 2018, respectively.

X
- Definition US Treasury payments [Table Text Block] + References No definition available. + Details
Name: | tve_USTreasurypaymentsTableTextBlock
Namespace Prefix: | tve_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

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