Stock-based compensation (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
Apr. 30, 2016	Jan. 31, 2016
Option activity [Line Items]
Granted	0
Weighted average grant date fair value	$ 0.00
Unrecognized compensation expense	$ 400
Unrecognized compensation expense recognized period	1 year 9 months 30 days
Restricted Stock [Member]
Option activity [Line Items]
Unrecognized compensation expense	$ 800
Unrecognized compensation expense recognized period	2 years 4 months 30 days
Stock Option [Member]
Option activity [Line Items]
Outstanding at beginning of year		720
Weighted Average Exercise Price Per Share		$ 11.38
Weighted Average Remaining Contractual Term		5 years 1 month 4 days
Options Outstanding Aggregate Intrinsic Value	$ 118	$ 34
Expired or forfeited	(42)
Expired or Forfeited Weighted Average Exercise Price Per Share	$ 9.63
Outstanding end of period	678
Outstanding Weighted Average Exercise Price Per Share	$ 11.49
Outstanding Weighted Average Remaining Contractual Term	4 years 8 months 30 days
Exercisable end of period	535
Exercisable Weighted Average Exercise Price Per Share	$ 12.00
Exercisable Weighted Average Remaining Contractual Term	3 years 10 months 8 days
Exercisable Aggregate Intrinsic Value	$ 92
unvested option [Member]
Option activity [Line Items]
Outstanding at beginning of year	143	166
Weighted Average Exercise Price Per Share	$ 9.57	$ 9.51
Options Outstanding Aggregate Intrinsic Value	$ 0	$ 0
Vested	(2)
Expired or forfeited	(21)
Expired or Forfeited Weighted Average Exercise Price Per Share	$ 9.07

Unrecognized cost of unvested share-based compensation awards.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
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-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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-Paragraph 2
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For presentations that combine terminations, the number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan or that expired.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Weighted average price of options that were either forfeited or expired.

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Net number of share options (or share units) granted during the period.

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-Publisher FASB
-Name Accounting Standards Codification
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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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Number of options outstanding, including both vested and non-vested options.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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As of the balance sheet date, the number of shares into which fully vested and expected to vest stock options outstanding can be converted under the option plan.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term for fully vested and expected to vest options that are exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Weighted average remaining contractual term for fully vested and expected to vest options outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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Number of options vested.

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The weighted average price as of the balance sheet date at which grantees could acquire the underlying shares with respect to all outstanding stock options which are in the customized range of exercise prices.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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-Paragraph 2
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