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Note 2 - Investment in Innolectric (Details Textual) $ in Thousands, € in Millions | 3 Months Ended |  |
--- | --- | --- | ---
Mar. 31, 2023 USD ($) | Mar. 31, 2023 EUR (€) | Mar. 31, 2022 USD ($) | Mar. 31, 2023 EUR (€) | Feb. 01, 2023 USD ($)
Payments to Acquire Interest in Subsidiaries and Affiliates | $ 9,975 |  | $ (0) |  |
Innolectric AG [Member] |  |  |  |  |
Loans and Leases Receivable, Related Parties | $ 2,000 |  |  | € 1.8 |
Loans and Leases Receivable, Interest Rate | 5.00% |  |  | 5.00% |
Innolectric AG [Member] |  |  |  |  |
Subsidiary, Ownership Percentage, Noncontrolling Owner |  |  |  |  | 33.33%
Payments to Acquire Interest in Subsidiaries and Affiliates | $ 8,800 | € 8.0 |  |  |
Business Acquisition, Transaction Costs |  |  |  |  | $ 1,300

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