Financial Statement Schedules - Schedule II - Valuation and Qualifying Accounts (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Jan. 31, 2014	Jan. 31, 2013	Jan. 31, 2012
Balance at end of period	$ 20,789	$ 19,965
Deferred Tax Assets Valuation Allowance [Member]
Balance at beginning of period	19,965	12,254	6,985
Additions, Charged to costs and expenses	824	7,711	5,269
Additions, Charged to other accounts
Deductions and write-offs
Balance at end of period	20,789	19,965	12,254
Allowance for Doubtful Accounts [Member]
Balance at beginning of period	946	1,127	1,141
Additions, Charged to costs and expenses	286		100
Additions, Charged to other accounts	31	13	12
Deductions and write-offs	(936)	(194)	(126)
Balance at end of period	$ 327	$ 946	$ 1,127