Accounts Receivable and Allowance for Doubtful Receivables - Allowance for Doubtful Receivables (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Aug. 31, 2013	Aug. 31, 2012	Aug. 31, 2013	Aug. 31, 2012
Receivables [Abstract]
Balance at beginning of period	$ 2,707	$ 4,479	$ 3,952	$ 4,403
Bad debt expense	1,099		2,198	287
Recoveries	14	13	19	19
Accounts written off	(72)	(82)	(2,421)	(299)
Balance at end of period	$ 3,748	$ 4,410	$ 3,748	$ 4,410