Change in Allowance for Doubtful Accounts (Detail) (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Oct. 31, 2011
Accounts, Notes, Loans and Financing Receivable [Line Items]
Beginning Balance	$ 3,941
Charged (credited) to expense	26
Deductions	(194)	[1]
Ending Balance	$ 3,773

[1] Specific account write-offs and foreign exchange.