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
Allowance for doubtful accounts [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Period	$ 3,374	$ 4,391	$ 2,666
Charged to Costs and Expenses	1,048	(361)	1,768
Charged to Other Accounts	(139)	20	1
Deductions Describe	(450)	(676)	(44)
Balance at End of Period	3,833	3,374	4,391
Allowance for obsolete equipment and inventory [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Period	1,073	901	730
Charged to Costs and Expenses	164	164	175
Charged to Other Accounts	(15)	8	(4)
Deductions Describe	(190)
Balance at End of Period	$ 1,032	$ 1,073	$ 901