Note 6 - Preferred Stock - Schedule of Stock by Class (Details) - USD ($) |
3 Months Ended | 6 Months Ended | 12 Months Ended | 24 Months Ended | 30 Months Ended | |||||
|---|---|---|---|---|---|---|---|---|---|---|
Jun. 30, 2025 |
Jun. 30, 2024 |
Jun. 30, 2025 |
Jun. 30, 2024 |
Dec. 31, 2024 |
Dec. 31, 2023 |
Dec. 31, 2024 |
Jun. 30, 2025 |
Jun. 05, 2025 |
Mar. 30, 2023 |
|
| Preferred stock, shares outstanding (in shares) | 355 | 355 | 545 | 545 | 355 | |||||
| Accrued Dividends amount | $ 25,000 | $ 64,000 | ||||||||
| Conversion of Series F Preferred Stock to Common Stock [Member] | ||||||||||
| Conversions, Shares Issued (in shares) | 45,163 | 198,894 | 45,163 | 288,947 | 288,947 | 352,624 | 641,571 | 686,734 | ||
| Accrued Dividends amount | $ 19,000 | $ 110,000 | $ 194,000 | |||||||
| Conversions, preferred (in shares) | (190) | (2,111) | (190) | (3,033) | ||||||
| Series F Preferred Stock [Member] | ||||||||||
| Preferred stock, shares outstanding (in shares) | 355 | 355 | 545 | 1,930 | 545 | 355 | ||||
| Balance dividend | $ 35,000 | $ 35,000 | $ 29,000,000 | $ 136,000,000 | $ 29,000,000 | $ 35,000 | ||||
| Convertible, Conversion Price (in dollars per share) | $ 3.77 | $ 3.77 | $ 11.17 | $ 13.6 | $ 11.17 | $ 3.77 | $ 3.77 | $ 68.4 | ||
| Issuance, preferred (in shares) | 1,648 | |||||||||
| Accrued Dividends amount | $ 25,000,000 | $ 89,000,000 | ||||||||
| Conversions, preferred (in shares) | (190) | (3,033) | ||||||||
| Conversions dividend | $ (19,000) | $ (196,000,000) | ||||||||
| Series F Preferred Stock [Member] | Weighted Average [Member] | ||||||||||
| Convertible, Conversion Price (in dollars per share) | $ 11.2 | $ 11.2 | ||||||||