Period of restriction of forfeiture.

No definition available.

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- Definition

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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- Definition

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

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- Definition

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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- 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

Total number of shares issued during the period, including shares forfeited, as a result of Restricted Stock Awards.

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Note 4 - Accounting for Stock-based Compensation (Details Textual) - USD ($)	3 Months Ended		9 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2020	Dec. 31, 2019
2006 Employee Equity Compensation Restricted Stock Plan (the "Employee Plan") [Member] \| Restricted Stock [Member]
Stock Issued During Period, Shares, Restricted Stock Award, Gross (in shares)			972,175
2016 Employee Equity Compensation Restricted Stock Plan [Member] \| Restricted Stock [Member]
Stock Issued During Period, Shares, Restricted Stock Award, Gross (in shares)			220,848
2006 Outside Director Equity Compensation Restricted Stock Plan (the "Director Plan") [Member] \| Restricted Stock [Member]
Stock Issued During Period, Shares, Restricted Stock Award, Gross (in shares)			272,000
2015 Outside Director Equity Compensation Restricted Stock Plan ("2015 Director Plan") [Member] \| Restricted Stock [Member]
Stock Issued During Period, Shares, Restricted Stock Award, Gross (in shares)			172,500
2015 Outside Director Equity Compensation Restricted Stock Plan ("2015 Director Plan") [Member] \| Restricted Stock [Member] \| Minimum [Member]
Restriction Period (Year)			1 year
2015 Outside Director Equity Compensation Restricted Stock Plan ("2015 Director Plan") [Member] \| Restricted Stock [Member] \| Maximum [Member]
Restriction Period (Year)			3 years
Employee and Director Plans [Member]
Share-based Payment Arrangement, Expense	$ 781,000	$ 716,000	$ 2,300,000	$ 2,100,000
Employee and Director Plans [Member] \| Restricted Stock [Member]
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total	$ 3,600,000	$ 3,400,000	$ 3,600,000	$ 3,400,000
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)			3 years	3 years
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number, Ending Balance (in shares)	177,000	183,000	177,000	183,000