Note 11 - Stock-based Compensation - Schedule of Allocation of Recognized Period Cost 2 (Details) - USD ($) |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Jun. 28, 2026 |
Jun. 29, 2025 |
Jun. 28, 2026 |
Jun. 29, 2025 |
|
| Total costs and expenses | $ 754 | $ 843 | $ 1,612 | $ 1,779 |
| Location, Statement of Income, Balance [Axis]: us-gaap:CostOfGoodsAndServicesSold | ||||
| Total costs and expenses | 158,000 | 189,000 | 314,000 | 347,000 |
| Location, Statement of Income, Balance [Axis]: us-gaap:ResearchAndDevelopmentExpense | ||||
| Total costs and expenses | 139,000 | 205,000 | 347,000 | 347,000 |
| Location, Statement of Income, Balance [Axis]: us-gaap:SellingGeneralAndAdministrativeExpense | ||||
| Total costs and expenses | $ 457,000 | $ 449,000 | $ 951,000 | $ 1,085,000 |