Note 8 - Earnings Per Share - Summary of Earnings Per Share (Details) - shares shares in Thousands	3 Months Ended	9 Months Ended
Oct. 31, 2018	Oct. 31, 2017	Oct. 31, 2018	Oct. 31, 2017
Basic weighted average common shares outstanding (in shares)	7,877	7,714	7,806	7,668
Dilutive effect of equity compensation plans (in shares)
Weighted average common shares outstanding assuming full dilution (in shares)	7,877	7,714	7,806	7,668
Stock options not included in the computation of diluted earnings per share of common stock because the option exercise prices exceeded the average market prices of the common shares (in shares)	176	143	176	143
Idaho [Member]
Stock options with an exercise price below the average market price (in shares)	90	226	90	226

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method.

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