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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Note 4 - Stock-based Compensation (Details Textual) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Restricted Stock [Member]
Shares Issued, Shares, Share-Based Payment Arrangement, after Forfeiture (in shares)	7,000	817,500	887,000	842,500
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount	$ 28.4		$ 28.4
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)			1 year 10 months 24 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	39,445	19,200
Share-Based Payment Arrangement, Option [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Gross (in shares)	0	0	2,112	0
Performance Shares [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period (Year)			2 years
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount	$ 0.1		$ 0.1
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)			1 year 8 months 12 days