Earnings per share (Details) In Thousands, unless otherwise specified	3 Months Ended
Apr. 30, 2013	Apr. 30, 2012
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Document Period End Date	Apr. 30, 2013
Basic weighted average common shares outstanding	6,932	6,915
Dilutive effect of deferred stock	2	0
Weighted average common shares outstanding assuming full dilution	6,934	6,915
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	486	303
Stock options with an exercise price below the average market price	469	519

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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+ Details

- Definition

The number of shares issued pursuant to the terms of the deferred compensation plan as of the balance sheet date.

+ References+ Details

- Definition

The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

+ References+ Details

- Definition

Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

+ References

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+ Details