Leases (Details) - USD ($) $ in Millions |
Jun. 30, 2022 |
Sep. 30, 2021 |
---|---|---|
Amounts Recognized on TVA's Consolidated Balance Sheet [Line Items] | ||
Finance lease, asset | $ 645 | $ 692 |
Finance Lease, Liability, Current | 0 | 25 |
Operating Lease, Liability, Noncurrent | 111 | 122 |
Finance Lease, Liability, Noncurrent | $ 648 | $ 687 |