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, 2014	Aug. 31, 2013	Aug. 31, 2014	Aug. 31, 2013
Receivables [Abstract]
Balance at beginning of period	$ 3,718	$ 2,707	$ 3,672	$ 3,952
Bad debt expense	87	1,099	231	2,198
Recoveries	8	14	19	19
Accounts written off	(229)	(72)	(338)	(2,421)
Balance at end of period	$ 3,584	$ 3,748	$ 3,584	$ 3,748