Note 12 - Subsequent Events (Details Textual) - USD ($) $ in Thousands	15 Months Ended
Jan. 31, 2017	Jul. 31, 2019
The 2015 Stock Repurchase Program [Member]
Stock Repurchased and Retired During Period, Shares	297,020
Stock Repurchased and Retired During Period, Value	$ 1,195
The 2019 Repurchase Plan [Member] \| Subsequent Event [Member]
Stock Repurchase Program, Authorized Amount		$ 3,000

Equity impact of the value of stock that has been repurchased and retired during the period. The excess of the purchase price over par value can be charged against retained earnings (once the excess is fully allocated to additional paid in capital).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Balance Type:	debit
Period Type:	duration