Note 4 - Inventories - Inventories, Current (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Raw materials and purchased parts for assembly	$ 11,539	$ 14,835
Self-manufactured assembly parts and finished products	16,906	20,486
Total	$ 28,445	$ 35,321

The aggregated amount of merchandise or goods held by the entity and readily available for future sale plus items held by the entity which are partially complete or in the process of being readied for future sale. This amount is net of valuation reserves and adjustments.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
-Topic 210
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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