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Note 3 - Divestiture of Subsidiary - Assets and Liabilities Included in Sale (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
	Jun. 01, 2023	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Gain on sale recognized		$ (135)	$ 0	$ 980	$ 0
Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member] \| Bel Stewart s.r.o. [Member]
Cash and cash equivalents	$ 2,072
Accounts receivable	1,030
Inventories	1,310
Property, plant and equipment	326
Other assets	48
Accounts payable	441
Accrued expenses	126
Income taxes payable	100
Other current liabilities	13
Other long-term liabilities	23
Total net assets transferred	4,083
Consideration received	5,063
Gain on sale recognized	$ 980