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Note 12 - Financial Instruments (Details Textual) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss, Current	$ 0	$ 46,000
Debt Instrument, Fair Value Disclosure	28,300,000	28,100,000
Fair Value of Total Debt Less of Carrying Value	5,000,000	5,200,000
Fair Value, Inputs, Level 2 [Member] | Bank Time Deposits and Government Agency Securities [Member]
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss, Current	$ 0	$ 46,000

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