Note 10 - Inventories - Summary of Inventories (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Finished goods	$ 33,122	$ 34,899
Raw materials, equipment spares and consumables	84,268	76,025
Work-in-progress	16,267	14,192
Total	$ 133,657	$ 125,116

Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of merchandise or goods held by the company that are readily available for sale.

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Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

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