Note 4 - China Joint Venture - Schedule of Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Cash and cash equivalents	$ 31,741	$ 43,652
Prepaid expenses and other current assets	1,655	2,764
Property and equipment, net	1,987	1,915
Accounts payable	2,615	2,712
Accrued expenses and other current liabilities	7,751	9,661
Corporate Joint Venture [Member]
Cash and cash equivalents	13	173
Prepaid expenses and other current assets	54	44
Property and equipment, net	247	262
Accounts payable	8	6
Accrued expenses and other current liabilities	$ 33	$ 0