Consolidated Statements of Stockholders’ Equity and Comprehensive Income (Loss) (USD $) In Thousands	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Treasury Stock [Member]
Stockholders equity at Feb. 28, 2009	$ 340,502	$ 246	$ 274,464	$ 91,513	$ (7,325)	$ (18,396)
Net income	22,483	0	0	22,483	0	0
Foreign currency translation adjustment	(685)	0	0	0	(685)	0
Reclassification adjustment for other-than-temporary impairment loss on available-for-sale security included in net income	1,000	0	0	0	1,000	0
Unrealized gain (loss) on marketable securities, net of tax effect	(268)	0	0	0	(268)	0
Other comprehensive income	47	0	0	0	0	0
Comprehensive income	22,530	0	0	0	0	0
Exercise of stock options into shares of common stock	85	1	84	0	0	0
Stock-based compensation expense	1,138	0	1,138	0	0	0
Issuance of shares of treasury stock	8	0	(2)	0	0	10
Stockholders equity at Feb. 28, 2010	364,263	247	275,684	113,996	(7,278)	(18,386)
Net income	23,031	0	0	23,031	0	0
Foreign currency translation adjustment	795	0	0	0	795	0
Reclassification of unrealized gains on marketable securities, net of tax effect	796	0	0	0	796	0
Reclassification adjustment for other-than-temporary impairment loss on available-for-sale security included in net income	1,600	0	0	0	1,600	0
Gain on derivatives designated for hedging	238	0	0	0	238	0
Other comprehensive income	3,429	0	0	0	0	0
Comprehensive income	26,460	0	0	0	0	0
Exercise of stock options into shares of common stock	932	1	931	0	0	0
Stock-based compensation expense	1,284	0	1,284	0	0	0
Issuance of shares of treasury stock	7	0	(3)	0	0	10
Stockholders equity at Feb. 28, 2011	392,946	248	277,896	137,027	(3,849)	(18,376)
Net income	25,649	0	0	25,649	0	0
Foreign currency translation adjustment		0	0	0	(1,153)	0
Reclassification of unrealized gains on marketable securities, net of tax effect	(65)	0	0	0	(65)	0
Reclassification adjustment for other-than-temporary impairment loss on available-for-sale security included in net income	1,225	0	0	0	1,225	0
Gain on derivatives designated for hedging		0	0	0	(131)	0
Other comprehensive income		0	0	0	0	0
Comprehensive income		0	0	0	0	0
Exercise of stock options into shares of common stock		2	2,235	0	0	0
Stock-based compensation expense		0	1,082	0	0	0
Issuance of shares of treasury stock	$ 7	$ 0	$ 0	$ 0	$ 0	$ 7
Stockholders equity at Feb. 29, 2012