Note 4 - Fair Value Measurements - Summary of Unrealized and Realized Gains and Losses on Equity Securities (Details) - USD ($) |
3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
Jun. 30, 2026 |
Jun. 30, 2025 |
Jun. 30, 2026 |
Jun. 30, 2025 |
|
| Net gains (losses) recognized during the period on equity securities | $ 546,129 | $ 0 | $ 4,357,467 | $ (349,078) |
| Less: net gains (losses) recognized during the period on equity securities sold during the period | 437,389 | 0 | 3,207,068 | (349,078) |
| Equity Securities, FV-NI, Unrealized Gain (Loss) | $ 108,740 | $ 0 | $ 1,150,399 | $ 0 |