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Note 11 - Financial Instruments (Details Textual) - USD ($) $ in Thousands | Mar. 31, 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, Total | 29,500,000 | 28,100,000
Fair Value of Total Debt Less of Carrying Value | 4,300,000 | 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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