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Note 2 - Investment in Innolectric (Details Textual) $ in Thousands, € in Millions			3 Months Ended		9 Months Ended
	Feb. 01, 2023 USD ($)	Feb. 01, 2023 EUR (€)	Sep. 30, 2025 USD ($)	Sep. 30, 2025 EUR (€)	Sep. 30, 2025 USD ($)	Sep. 30, 2025 EUR (€)	Sep. 30, 2025 EUR (€)	Dec. 31, 2024 USD ($)	Dec. 31, 2024 EUR (€)
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures			$ 9,960		$ 9,960			$ 9,265
Innolectric AG [Member]
Loans and Leases Receivable, Related Parties, Additions | €				€ 0.2		€ 0.5
Loans and Leases Receivable, Related Parties			$ 3,900		$ 3,900		€ 3.3	$ 2,900	€ 2.8
Loans and Leases Receivable, Interest Rate			5.00%		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
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures	11,000
Business Combination, Consideration Transferred, Liabilities Incurred	$ 1,000
Net Income (Loss) Attributable to Noncontrolling Interest			$ (300)		$ (400)

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