Note 7 - Inventories - Inventories (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Raw materials	$ 29,085	$ 25,555
Work in process and sub-assemblies	46,558	52,544
Finished goods	24,756	32,298
Total inventories	$ 100,399	$ 110,397

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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