Note 4 - Fair Value Measurements - Summary of Unrealized and Realized Gains and Losses on Equity Securities (Details) - USD ($) |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Mar. 31, 2026 |
Mar. 31, 2025 |
Mar. 31, 2026 |
Mar. 31, 2025 |
|
| Net gains (losses) recognized during the period on equity securities | $ 3,931,416 | $ 0 | $ 3,811,338 | $ (349,078) |
| Less: net gains (losses) recognized during the period on equity securities sold during the period | 1,954,544 | 0 | 2,081,146 | (349,078) |
| Equity Securities, FV-NI, Unrealized Gain (Loss) | $ 1,976,872 | $ 0 | $ 1,730,192 | $ 0 |
| X | ||||||||||
- Definition Amount of unrealized and realized gain (loss) on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI). Reference 1: http://www.xbrl.org/2003/role/disclosureRef
|
| X | ||||||||||
- Definition Amount of realized gain (loss) from sale of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI). Reference 1: http://www.xbrl.org/2003/role/disclosureRef
|
| X | ||||||||||
- Definition Amount of unrealized gain (loss) on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI). Reference 1: http://www.xbrl.org/2003/role/disclosureRef
|