Income Taxes (Narrative) (Details) - USD ($) $ in Millions |
6 Months Ended | |
|---|---|---|
Mar. 31, 2026 |
Sep. 30, 2025 |
|
| Net operating loss carryforward | $ 6.4 | |
| Operating loss carryforwards, expiration | will carry forward indefinitely | |
| Federal tax credit carryforward | $ 26.9 | $ 22.3 |
| Tax credit carryforward, expiration | Federal tax credits carry forward for 20 years. | |
| Domestic Tax Jurisdiction [Member] | ||
| Operating loss carryforwards | $ 25.3 | |
| State and Local Jurisdiction [Member] | ||
| Operating loss carryforwards | $ 34.6 |