Note 6 - Fair Value Measurements - Derivative Liability Measured at Fair Value (Details) - USD ($) $ in Thousands	12 Months Ended
Mar. 31, 2026	Mar. 31, 2025	Mar. 31, 2024
Change in fair value	$ 4,171	$ 6,682	$ 4,922
Comtrafo Industria de Transformadores Eletricos S.A. (Comtrafo) [Member]
Change in fair value	4,200
Derivative Financial Instruments, Liabilities [Member] \| Comtrafo Industria de Transformadores Eletricos S.A. (Comtrafo) [Member]
Balance	0
Issuance of contingent consideration	34,815
Change in fair value	4,171
FX Impact	543
Balance	$ 39,529	$ 0

Amount of foreign exchange impact recognized from liability measured at fair value on recurring basis using unobservable input (level 3).

No definition available.

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- Definition

Amount of gain (loss) recognized in income from liability measured at fair value on recurring basis using unobservable input (level 3).

+ References

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- Definition

Amount of issuances of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-3

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2G
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2G

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

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- Definition

Fair value of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

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