Income taxes UTP (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Jan. 31, 2015	Jan. 31, 2014	Jan. 31, 2013
Income Tax Contingency [Line Items]
Balance at beginning of the year		$ 1,358us-gaap_UnrecognizedTaxBenefits	$ 1,373us-gaap_UnrecognizedTaxBenefits
Increases in positions taken in a prior period	17	0
Increases in positions taken in a current period	0	11
Decreases due to lapse of statute of limitations	(42)	(26)
Unrecognized Tax Benefits, Decrease Resulting from Settlements with Taxing Authorities	(45)	0
Unrecognized tax benefits that would impact effective tax rate	1,288
Unrecognized tax benefits, interest	17	18
Unrecognized tax benefits, income tax penalties	$ 15	$ 25

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Amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns.

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-Name Accounting Standards Codification

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Amount of decrease in unrecognized tax benefits resulting from settlements with taxing authorities.

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Amount of statutory penalties accrued for a tax position claimed or expected to be claimed by the entity, in its tax return.

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Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.

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Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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Amount of interest expense accrued for an underpayment of income taxes.

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Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations.

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The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

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