Earnings per share (Details) In Thousands, unless otherwise specified	3 Months Ended
Apr. 30, 2014	Apr. 30, 2013
Earnings per share [Line Items]
Basic weighted average common shares outstanding	7,177	6,932
Dilutive effect of equity incentive plans	138	2
Weighted average common shares outstanding assuming full dilution	7,315	6,934
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	160	486
Stock options with an exercise price below the average market price	547	469

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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 260

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Antidilution

-URI http://asc.fasb.org/extlink&oid=6505113

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Diluted Earnings Per Share

-URI http://asc.fasb.org/extlink&oid=6510752

Reference 4: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 260

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The sum of dilutive potential common shares or units used in the calculation of the diluted per-share or per-unit computation.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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