Income Taxes - Schedule of Deferred Tax Assets and Liabilities (Detail) (USD $) In Thousands, unless otherwise specified	Jan. 31, 2013	Jan. 31, 2012
Deferred tax assets:
Deferred revenue		$ 83
Federal and state credits	1,243	1,301
Expenses not currently deductible	1,345	895
Foreign deferred	60	38
Stock-based compensation	950	451
Gross deferred tax assets	3,598	2,768
Valuation allowance	(1,243)	(1,301)
Total deferred tax assets	2,355	1,467
Deferred tax liabilities
Property and equipment	(197)	(180)
Net deferred tax assets	$ 2,158	$ 1,287