Stock options Unvested options (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Jan. 31, 2016	Jan. 31, 2015
percentage of options expect to vest	85.00%
unvested option [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Number of Shares	166	232
Shares Authorized under Stock Option Plans, Exercise Price Range, Outstanding Options, Weighted Average Exercise Price	$ 9.51	$ 10.11
Share-based Payment Award, Options, Outstanding, Intrinsic Value	$ 3	$ 0
Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price	$ 6.38	$ 12.41
Vested options in the period	(92)
Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures and Expirations in Period	25
Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures and Expirations in Period, Weighted Average Exercise Price	$ 9.65