Correction of immaterial errors Adjustments to the previously reported statement of cash flows (Details) - USD ($) $ in Thousands	12 Months Ended
	Jan. 31, 2016	Jan. 31, 2015
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Net loss	$ (4,409)	$ (181)
Change in Inventories	(4,027)	(3,250)
Prepaid expenses and other current assets	$ 1,914	1,000
Scenario, Previously Reported [Member]
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Net loss		(256)
Change in Inventories		(3,348)
Prepaid expenses and other current assets		(977)
Restatement Adjustment [Member]
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Net loss		75
Change in Inventories		98
Prepaid expenses and other current assets		$ (23)