Note 7 - Fair Value Measurements - Assets and Liabilities Carried at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Mar. 31, 2026
Contingent consideration, current portion	$ 3,959	$ 12,808
Contingent consideration, long-term portion	27,930	26,721
Fair Value, Recurring [Member] \| Reported Value Measurement [Member]
Cash equivalents	96,924	101,525
Contingent consideration, current portion	3,959	12,808
Contingent consideration, long-term portion	27,930	26,721
Fair Value, Recurring [Member] \| Reported Value Measurement [Member] \| Short-term Cash Instruments [Member]
Short-term cash instruments	1,585	1,278
Fair Value, Recurring [Member] \| Reported Value Measurement [Member] \| Fair Value, Inputs, Level 1 [Member]
Cash equivalents	96,924	101,525
Contingent consideration, current portion	0	0
Contingent consideration, long-term portion	0	0
Fair Value, Recurring [Member] \| Reported Value Measurement [Member] \| Fair Value, Inputs, Level 1 [Member] \| Short-term Cash Instruments [Member]
Short-term cash instruments	0	0
Fair Value, Recurring [Member] \| Reported Value Measurement [Member] \| Fair Value, Inputs, Level 2 [Member]
Cash equivalents	0	0
Contingent consideration, current portion	0	0
Contingent consideration, long-term portion	0	0
Fair Value, Recurring [Member] \| Reported Value Measurement [Member] \| Fair Value, Inputs, Level 2 [Member] \| Short-term Cash Instruments [Member]
Short-term cash instruments	1,585	1,278
Fair Value, Recurring [Member] \| Reported Value Measurement [Member] \| Fair Value, Inputs, Level 3 [Member]
Cash equivalents	0	0
Contingent consideration, current portion	3,959	12,808
Contingent consideration, long-term portion	27,930	26,721
Fair Value, Recurring [Member] \| Reported Value Measurement [Member] \| Fair Value, Inputs, Level 3 [Member] \| Short-term Cash Instruments [Member]
Short-term cash instruments	$ 0	$ 0

Amount of liability recognized arising from contingent consideration in a business combination, expected to be settled within one year or the normal operating cycle, if longer.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 805
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479581/805-30-50-2

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
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Amount of liability recognized arising from contingent consideration in a business combination, expected to be settled beyond one year or the normal operating cycle, if longer.

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 820
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Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
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Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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