Commitments (Rent Expense) (Details) - USD ($) $ in Thousands	12 Months Ended
Jan. 31, 2018	Jan. 31, 2017	Jan. 31, 2016
Commitments [Abstract]
Rent expense	$ 5,644	$ 5,735	$ 5,681

Amount of rent expense incurred for leased assets, including but not limited to, furniture and equipment, that is not directly or indirectly associated with the manufacture, sale or creation of a product or product line.

No definition available.

Name:	us-gaap_LeaseAndRentalExpense
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration