Note 5 - Prepaid Expenses and Other Current Assets - Prepaid Expenses and Other Current Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Prepaid insurance	$ 1,044	$ 1,012
Prepaid supplier expenses	167	132
Other receivables	204	159
Natural gas derivatives at fair value, current	207	0
Deposits	129	237
Other	151	137
Total prepaid expenses and other current assets	$ 1,902	$ 1,677