Note 7 - Accounts Payable and Accrued Expenses - Summary of Accounts Payable and Accrued Expenses (Details) - USD ($) $ in Thousands |
Dec. 31, 2025 |
Dec. 31, 2024 |
|---|---|---|
| Accounts payable | $ 1,012 | $ 826 |
| Accrued payroll | 199 | 120 |
| Accounts payable and accrued expenses, total | 1,211 | 946 |
| Segment Reporting, Reconciling Item, Corporate Nonsegment [Member] | ||
| Accounts payable | 588 | 221 |
| Accrued payroll | 10 | 12 |
| Operating Segments [Member] | Odor-No-More [Member] | ||
| Accounts payable | 305 | 511 |
| Accrued payroll | 85 | 68 |
| Operating Segments [Member] | BLEST [Member] | ||
| Accounts payable | 0 | 73 |
| Accrued payroll | 73 | 40 |
| Operating Segments [Member] | BioLargo Canada [Member] | ||
| Accounts payable | 100 | 24 |
| Accrued payroll | 22 | 0 |
| Operating Segments [Member] | BioLargo Energy Technologies, Inc (BETI) [Member] | ||
| Accounts payable | 43 | 31 |
| Accrued payroll | 0 | 0 |
| Operating Segments [Member] | BEST [Member] | ||
| Accounts payable | 0 | 0 |
| Accrued payroll | 9 | 0 |
| Consolidation, Eliminations [Member] | ||
| Accounts payable | (24) | (34) |
| Accrued payroll | $ 0 | $ 0 |