Note 4 - Equity - Stock Option Activity (Details) - $ / shares |
3 Months Ended | 6 Months Ended | ||||
|---|---|---|---|---|---|---|
Jun. 30, 2026 |
Mar. 31, 2026 |
Jun. 30, 2025 |
Mar. 31, 2025 |
Jun. 30, 2026 |
Jun. 30, 2025 |
|
| Outstanding, number of shares (in shares) | 300 | 300 | 300 | 301 | 300 | 301 |
| Outstanding, weighted average exercise price (in dollars per share) | $ 134,934.51 | $ 134,934.51 | $ 134,526.78 | $ 134,392.67 | $ 134,934.51 | $ 134,392.67 |
| Options expired or cancelled, number of shares (in shares) | 95 | 0 | 0 | 1 | 95 | 0 |
| Options expired or cancelled, weighted average exercise price (in dollars per share) | $ 111,904.51 | $ 0 | $ 0 | $ 94,160 | $ 111,904.51 | |
| Outstanding, number of shares (in shares) | 205 | 300 | 300 | 300 | 205 | 300 |
| Outstanding, weighted average exercise price (in dollars per share) | $ 152,847.85 | $ 134,934.51 | $ 134,526.78 | $ 134,526.78 | $ 152,847.85 | $ 134,526.78 |