Nature of Operations, Segment Reporting and Geographical Information - Additional Information (Detail) $ in Thousands	12 Months Ended
Jan. 31, 2017 USD ($) Customer Segment	Jan. 31, 2016 USD ($) Customer	Jan. 31, 2015 Customer
Segment Reporting Information [Line Items]
Number of reporting segments \| Segment	2
Customer accounted for greater than 10% of net sales \| Customer	0	0	0
Goodwill assigned	$ 4,521	$ 4,521
T&M [Member]
Segment Reporting Information [Line Items]
Goodwill assigned	$ 4,500	$ 4,500

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=64834752&loc=SL49117168-202975

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