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, 2022	Jun. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Restricted Stock [Member]
Shares Issued, Shares, Share-Based Payment Arrangement, after Forfeiture, Total (in shares)	338,500	338,500			309,700
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total	$ 5.2			$ 5.2
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, Total (in shares)				25,806	166,648
Immediately Vested Common Stock Issued in Lieu of Cash Bonuses [Member]
Shares Issued, Shares, Share-Based Payment Arrangement, after Forfeiture, Total (in shares)			47,604		158,356
Share-Based Payment Arrangement, Option [Member]
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total	$ 0.1			$ 0.1
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)				1 year 8 months 12 days
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Gross (in shares)	0		0	20,564	0