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Note 1 - Description of Business and Summary of Significant Accounting Policies (Details Textual) - USD ($) shares in Thousands, $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2022 | Dec. 31, 2021
Foreign Currency Transaction Gain (Loss), before Tax, Total | $ 278 | $ (44)
Intangible Assets, Percent of Total Assets | 9.70% | 11.90%
Excessive Dividend Rate of Class B Over Class A | 5.00% |
Excessive Undistributed Earnings Allocation Rate of Class B Over Class A | 5.00% |
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount (in shares) | 0 |
Research and Development Expense, Total | $ 20,238 | $ 21,891
Maximum [Member] |  |
Foreign Currency Transaction Gain (Loss), before Tax, Total |  | $ (100)
Standard Product Warranty, Period (Year) | 3 years |
Finite-Lived Intangible Asset, Useful Life (Year) | 16 years |
Maximum [Member] | Building and Building Improvements [Member] |  |
Property, Plant and Equipment, Useful Life (Year) | 33 years |
Maximum [Member] | Machinery and Equipment [Member] |  |
Property, Plant and Equipment, Useful Life (Year) | 14 years |
Minimum [Member] |  |
Standard Product Warranty, Period (Year) | 1 year |
Finite-Lived Intangible Asset, Useful Life (Year) | 1 year |
Minimum [Member] | Building and Building Improvements [Member] |  |
Property, Plant and Equipment, Useful Life (Year) | 1 year |
Minimum [Member] | Machinery and Equipment [Member] |  |
Property, Plant and Equipment, Useful Life (Year) | 3 years |

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- Definition Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (c) -URI https://asc.fasb.org/extlink&oid=124432515&loc=d3e3550-109257 + Details
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