Note 9 - Stock Based Compensation - Activities Within the Stock Option Plan (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	12 Months Ended
Jun. 30, 2024	Mar. 31, 2024
Outstanding, number of options (in shares)	721,793
Granted, number of options (in shares)	198,130
Exercisable, number of options (in shares)	378,174
Outstanding, number of options (in shares)	919,923	721,793
Outstanding, weighted average exercise price	$ 3.68
Granted, weighted average exercise price	2.96
Outstanding, weighted average exercise price	3.53	$ 3.68
Exercisable, weighted average exercise price	$ 4.41
Outstanding Remaining Contractual Term (years)	9 years 18 days	9 years 29 days
Exercisable Remaining Contractual Term (years)	8 years 7 months 24 days
Aggregate Intrinsic Value Beginning	$ 527
Aggregate Intrinsic Value Closing	241	$ 527
Aggregate Intrinsic Value, Exercisable	$ 115

The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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Gross number of share options (or share units) granted during the period.

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Number of options outstanding, including both vested and non-vested options.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(i)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

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-Section 50
-Paragraph 2
-Subparagraph (c)(1)(ii)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Amount by which current fair value of underlying stock exceeds exercise price of fully vested and expected to vest exercisable or convertible options. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
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-Section 50
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-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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Intrinsic value of outstanding award under share-based payment arrangement. Excludes share and unit options.

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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