Note 4 - Stock-based Compensation (Details Textual) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2024	Dec. 31, 2023
Restricted Stock [Member]
Shares Issued, Shares, Share-Based Payment Arrangement, after Forfeiture (in shares)	30,000	0	872,500	681,500
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)	1 year 7 months 6 days
Restricted Stock [Member] \| Minimum [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period (Year)	2 years
Restricted Stock [Member] \| Maximum [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period (Year)	3 years
Immediately Vested Common Stock [Member]
Shares Issued, Shares, Share-Based Payment Arrangement, after Forfeiture (in shares)	0	0	19,200	53,675
Share-Based Payment Arrangement, Option [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Gross (in shares)	0	0	0	0
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount	$ 18.2		$ 18.2

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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Number, after forfeiture, of shares or units issued under share-based payment arrangement. Excludes shares or units issued under employee stock ownership plan (ESOP).

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