Note 8 - Leases - Components of Lease Expense and Cash Flows from Leases (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Amortization of right-of use assets, included in cost of goods sold	$ 20	$ 21
Interest on lease liabilities	2	3
Fixed leases cost	129	129
Variable lease cost	46	38
Short-term lease cost	7	0
Total lease cost	204	191
Operating cash flows from finance leases	2	4
Operating cash flows from operating leases	129	129
Financing cash flows from finance leases	$ 24	$ 26