Note 11 - Treasury Stock and Repurchase Program - Treasury Stock at Cost (Details) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended	3 Months Ended
Jul. 31, 2020	Jun. 30, 2020	May 31, 2020	Jul. 31, 2020	Jul. 31, 2019	Apr. 30, 2020
Treasury stock, shares (in shares)	383,279			383,279		383,279
Balance, total average cost assigned	$ 5,957			$ 5,957		$ 5,957
Balance, average cost per share (in dollars per share)	$ 15.54			$ 15.54		$ 15.54
Balance, aggregate purchase price remaining under the program	$ 2,000	$ 2,000	$ 2,000	$ 2,000		$ 2,000
Purchases effected in open market, shares (in shares)				0
Purchases effected in open market, total average cost assigned					$ 92
Purchases effected in open market, average cost per share (in dollars per share)

Amount remaining of a stock repurchase plan authorized.

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- Definition

Total cost of shares repurchased divided by the total number of shares repurchased.

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- Definition

Number of common and preferred shares that were previously issued and that were repurchased by the issuing entity and held in treasury on the financial statement date. This stock has no voting rights and receives no dividends.

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Number of shares that have been repurchased during the period and are being held in treasury.

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The amount allocated to treasury stock. Treasury stock is common and preferred shares of an entity that were issued, repurchased by the entity, and are held in its treasury.

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Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method.

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Represents the average cost per share.

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