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 grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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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 ($)	1 Months Ended	3 Months Ended		9 Months Ended
	Dec. 31, 2021	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2021	Dec. 31, 2020
Employee and Director Plans [Member]
Share-based Payment Arrangement, Expense		$ 1,400,000	$ 781,000	$ 3,000,000.0	$ 2,300,000
Restricted Stock [Member] \| The 2016 Employee Equity Compensation Restricted Stock Plan [Member]
Stock Issued During Period, Shares, Restricted Stock Award, Gross (in shares)				875,825
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares)	15,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value (in USD per Share)	$ 27.10
Restricted Stock [Member] \| 2015 Outside Director Equity Compensation Restricted Stock Plan ("2015 Director Plan") [Member]
Stock Issued During Period, Shares, Restricted Stock Award, Gross (in shares)				203,880
Restricted Stock [Member] \| 2015 Outside Director Equity Compensation Restricted Stock Plan ("2015 Director Plan") [Member] \| Minimum [Member]
Restriction Period (Year)				1 year
Restricted Stock [Member] \| 2015 Outside Director Equity Compensation Restricted Stock Plan ("2015 Director Plan") [Member] \| Maximum [Member]
Restriction Period (Year)				3 years
Restricted Stock [Member] \| Employee and Director Plans [Member]
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total	$ 14,400,000	$ 14,400,000	$ 3,600,000	$ 14,400,000	$ 3,600,000
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)				3 years
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number, Ending Balance (in shares)	749,000	749,000	177,000	749,000	177,000