Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation.

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

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Note 3 - Accounting for Stock-based Compensation (Details Textual) - USD ($)	3 Months Ended		9 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2017	Dec. 31, 2016
2006 Employee Equity Compensation Restricted Stock Plan (the "Employee Plan") [Member] \| Restricted Stock [Member]
Stock Issued During Period, Shares, Restricted Stock Award, Gross			974,860
2016 Employee Equity Compensation Restricted Stock Plan [Member]
Stock Issued During Period, Shares, Restricted Stock Award, Gross			47,600
2006 Outside Director Equity Compensation Restricted Stock Plan (the "Director Plan") [Member] \| Restricted Stock [Member]
Stock Issued During Period, Shares, Restricted Stock Award, Gross			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			60,000
Employee and Director Plans [Member] \| Restricted Stock [Member]
Allocated Share-based Compensation Expense	$ 712,000	$ 498,000	$ 1,900,000	$ 1,400,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition			3 years
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	233,000	273,000	233,000	273,000
Employee and Director Plans [Member] \| Restricted Stock [Member] \| General and Administrative Expense [Member]
Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Share-based Awards Other than Options	$ 5,100,000	$ 3,800,000	$ 5,100,000	$ 3,800,000