Lease information Future minimum payments (Details) (USD $) In Thousands, unless otherwise specified	Jan. 31, 2015	Jan. 31, 2014
Operating Leased Assets [Line Items]
Operating Leases, Future Minimum Payments Due, Next Twelve Months	$ 1,707
Capital Lease Obligations, Current	783
Operating Leases, Future Minimum Payments, Due in Two Years	1,389
Capital Leases, Future Minimum Payments Due in Two Years	746
Operating Leases, Future Minimum Payments, Due in Three Years	1,287
Capital Leases, Future Minimum Payments Due in Three Years	254
Operating Leases, Future Minimum Payments, Due in Four Years	1,247
Capital Leases, Future Minimum Payments Due in Four Years	120
Operating Leases, Future Minimum Payments, Due in Five Years	1,187
Capital Leases, Future Minimum Payments Due in Five Years	124
Operating Leases, Future Minimum Payments, Due Thereafter	13,510
Capital Leases, Future Minimum Payments Due Thereafter	14
Operating Leases, Future Minimum Payments Due	20,327
Capital leases, future minimum payments, interest included in payments	2,041
Interest Portion of Minimum Lease Payments, Sale Leaseback Transactions	135
Capital Lease Obligations	$ 1,906	$ 2,067