Stock Based Compensation - Summarizes Information Relating to Stock Options Granted and Exercised (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
Jan. 31, 2014	Jan. 31, 2013	Jan. 31, 2012
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Weighted average fair value of options granted	$ 6.80	$ 5.39	$ 6.37
Aggregate intrinsic value of options exercised	$ 528	$ 287	$ 285

Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (d)(2)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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