Note 5 - Accrued Liabilities - Schedule of Accrued Liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2025	Dec. 31, 2024
Accrued compensation and related charges	$ 2,917	$ 2,832
Preferred stock dividends payable	2,901	2,901
Payable in connection with construction in progress	1,929	1,985
Accrued professional services	609	1,460
Other tax payable	573	399
Current portion of operating lease liabilities	550	536
Accrued product warranty	435	451
Accrued income taxes	371	127
Advances from customers	331	1,590
Other personnel-related costs	258	256
Accrual for sales returns	36	28
Other accrued liabilities	1,462	1,991
Accrued Liabilities, Current	$ 12,372	$ 14,556