Note 5 - Fair Value Measurements (Details Textual) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Derivative Asset, Total	$ 57	$ 12
Long-term Debt, Fair Value	112,500	118,400
Long-term Debt, Gross	112,500	115,600
Fair Value, Nonrecurring [Member]
Assets, Fair Value Disclosure	0	0
Foreign Exchange Forward [Member] \| Maximum [Member]
Derivative Asset, Total	100	100
Interest Rate Swap [Member]
Derivative Asset, Total	100
Investments Held in Rabbi Trust [Member]
Debt Securities, Available-for-sale, Total	$ 300	$ 700

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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