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Note 11 - Shareholders' Equity (Details Textual) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended	3 Months Ended	9 Months Ended
	May 30, 2026	Jun. 30, 2026	Sep. 30, 2026	Sep. 30, 2025	Jan. 01, 2027	Dec. 31, 2025	Nov. 14, 2024
Proceeds from Issuance of Common Stock			$ 441,643	$ 0
Long-Term Debt, Gross			$ 0			$ 197,500
Enercon Technologies, Ltd [Member]
Business Acquisition, Percentage of Voting Interests Acquired			20.00%				80.00%
Enercon Technologies, Ltd [Member] \| Forecast [Member]
Business Acquisition, Percentage of Voting Interests Acquired					20.00%
Revolving Credit Facility [Member] \| Credit and Security Agreement with KeyBank [Member]
Repayments of Debt		$ 197,500
Long-Term Debt, Gross			$ 0
Common Class B [Member] \| Follow-On Public Offering [Member]
Stock Issued During Period, Shares, New Issues (in shares)	1,725,000
Shares Issued, Price Per Share (in dollars per share)	$ 266
Proceeds from Issuance of Common Stock	$ 458,900
Proceeds From Issuance of Common Stock, Net	$ 441,600
Common Class B [Member] \| Over-Allotment Option [Member]
Stock Issued During Period, Shares, New Issues (in shares)	225,000