Dividend rate of class B in excess of dividend rate of class A.

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Undistributed earnings allocated to class B of common stock in excess of earnings allocated to class A.

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The percent total assets that are intangible assets.

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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.

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Amount of assets held-for-sale that are not part of a disposal group, expected to be sold within a year or the normal operating cycle, if longer.

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Face amount or stated value per share of common stock.

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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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No definition available.

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Amount, before tax, of realized and unrealized gain (loss) from foreign currency transaction.

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The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of an intangible asset (excluding goodwill) to fair value.

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The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

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Term of warranty or group of similar warranties, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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Amount of expense for research and development. Includes, but is not limited to, cost for computer software product to be sold, leased, or otherwise marketed and writeoff of research and development assets acquired in transaction other than business combination or joint venture formation or both. Excludes write-down of intangible asset acquired in business combination or from joint venture formation or both, used in research and development activity.

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Note 1 - Description of Business and Summary of Significant Accounting Policies (Details Textual) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Nov. 14, 2024
Gain (Loss), Foreign Currency Transaction, before Tax	$ 1,900	$ (1,400)	$ 300
Intangible Assets, Percent of Total Assets	24.40%	8.60%
Asset, Held-for-Sale, Not Part of Disposal Group, Current	$ 2,062	$ 1,278
Impairment of Intangible Assets (Excluding Goodwill)	$ 400	$ 0	$ 0
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	0	0
Research and Development Expense	$ 23,586	$ 22,487	$ 20,238
Common Class B [Member]
Common Stock, Par or Stated Value Per Share (in dollars per share)	$ 0.1	$ 0.1
Common Class A [Member]
Common Stock, Par or Stated Value Per Share (in dollars per share)	$ 0.1	$ 0.1
Trade Names [Member]
Impairment of Intangible Assets (Excluding Goodwill)	$ 400
Minimum [Member]
Product Warranty Obligation, Term (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
Maximum [Member]
Product Warranty Obligation, Term (Year)	3 years
Finite-Lived Intangible Asset, Useful Life (Year)	17 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
Enercon Technologies, Ltd [Member]
Subsidiary, Ownership Percentage, Parent				80.00%