Financing Arrangements - Debt Issuance Costs (Details) - USD ($) $ in Thousands	Jan. 31, 2018	Jan. 31, 2017
JPMorgan Chase Bank
Line of Credit Facility [Line Items]
Unamortized debt issuance costs(a)	$ 242	$ 352

Amount of unamortized debt discount (premium) and debt issuance costs.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28555-108399

Name:	us-gaap_DebtInstrumentUnamortizedDiscountPremiumAndDebtIssuanceCostsNet
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant