Lease information Property under capitalized leases (Details) - USD ($) $ in Thousands	12 Months Ended
	Jan. 31, 2016	Jan. 31, 2015
Property, Plant and Equipment [Line Items]
Capital leases transportation equipment	$ 22	$ 24
Capitalized computer equipment	0	92
Capital leased assets, gross	1,769	1,919
Capital leases other accumulated depreciation	726	691
Capital leases, net	1,043	1,228
Fixed assets acquired under capital leases	0	680
Other Capitalized Property Plant and Equipment [Member]
Property, Plant and Equipment [Line Items]
Capital leases machinery and equipment	$ 1,747	$ 1,803