Represents percentage of automatic increase in the amount of shares available for issuance.

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- Definition

Period of restriction of forfeiture.

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No definition available.

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Aggregate number of common shares reserved for future issuance.

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- Definition

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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Amount of noncash expense for share-based payment arrangement.

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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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- Definition

Number of shares issued during the period related to Restricted Stock Awards, net of any shares forfeited.

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Note 7 - Restricted Stock (Details Textual) - USD ($) $ in Thousands	1 Months Ended			12 Months Ended
	Jul. 31, 2016	Jul. 31, 2015	Jul. 31, 2012	Mar. 31, 2021	Mar. 31, 2020	Mar. 31, 2019	Jul. 28, 2006
Percentage of Automatic Increase in Shares Available for Issuance			10.00%
Share-based Payment Arrangement, Noncash Expense, Total				$ 3,307	$ 2,822	$ 3,097
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number, Ending Balance (in shares)				160,000	183,000
2006 Employee Equity Compensation Restricted Stock Plan (the "Employee Plan") \| Restricted Stock [Member]
Common Stock, Capital Shares Reserved for Future Issuance (in shares)				972,175			1,000,000.0
2006 Outside Director Equity Compensation Restricted Stock Plan (the "Director Plan") [Member] \| Restricted Stock [Member]
Common Stock, Capital Shares Reserved for Future Issuance (in shares)			400,000	272,000			200,000
2015 Outside Director Equity Compensation Restricted Stock Plan [Member] \| Restricted Stock [Member]
Common Stock, Capital Shares Reserved for Future Issuance (in shares)		400,000
Percentage of Automatic Increase in Shares Available for Issuance		10.00%
2016 Employee Equity Compensation Restricted Stock Plan [Member] \| Restricted Stock [Member]
Common Stock, Capital Shares Reserved for Future Issuance (in shares)	1,000,000			219,039
2016 Employee Equity Compensation Restricted Stock Plan [Member] \| Restricted Stock [Member] \| Minimum [Member]
Restriction Period (Year)	1 year
2016 Employee Equity Compensation Restricted Stock Plan [Member] \| Restricted Stock [Member] \| Maximum [Member]
Restriction Period (Year)	10 years
2016 Outside Director Equity Compensation Restricted Stock Plan [Member] \| Restricted Stock [Member]
Common Stock, Capital Shares Reserved for Future Issuance (in shares)				172,500
Employee and Director Equity Compensation Plan [Member] \| Non-vested Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number, Ending Balance (in shares)				160,117	182,695
Stock Issued During Period, Shares, Restricted Stock Award, Net of Forfeitures, Total (in shares)				102,931	105,925
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total				$ 2,500	$ 2,600
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)				1 year 9 months 18 days	1 year 9 months 18 days