Change in Allowance for Doubtful Accounts (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Jan. 31, 2012		Jan. 31, 2011		Jan. 31, 2010
Accounts, Notes, Loans and Financing Receivable [Line Items]
Beginning balance	$ 3,941		$ 3,607		$ 5,515
Charged to expense	688		369		(15)
Other changes	(197)	[1]	(35)	[1]	(1,893)	[1]
Ending balance	$ 4,432		$ 3,941		$ 3,607

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