Note 2 - Investments - Change in Estimate of Credit Losses (Details) - USD ($) |
6 Months Ended | 12 Months Ended |
|---|---|---|
Jun. 30, 2026 |
Dec. 31, 2025 |
|
| Beginning balance | $ (529,984) | $ (725,960) |
| Debt Securities, Available-for-Sale, Excluding Accrued Interest, Allowance for Credit Loss, Period Increase (Decrease) | (67,185) | (195,976) |
| Debt Securities, Available-for-Sale, Excluding Accrued Interest, Allowance for Credit Loss, Period Increase (Decrease) | 67,185 | 195,976 |
| Ending balance | $ (597,169) | $ (529,984) |