Note 7 - Selected Balance Sheet Data - Schedule Of Inventory (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Raw materials	$ 18,962	$ 14,764
Work-in process	1,646	2,467
Finished products	1,623	2,282
Inventories	22,231	19,513
Domestic Inventories [Member]
Raw materials	14,400	11,371
Work-in process	690	1,499
Finished products	1,490	2,149
Inventories	16,580	15,019
Foreign Inventories [Member]
Raw materials	4,562	3,393
Work-in process	956	968
Finished products	133	133
Inventories	$ 5,651	$ 4,494

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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