Consolidated Statements of Stockholders' Equity (USD $)	Total	Paid-in Capital	Common Stock	Treasury Stock	Retained Earnings
Beginning balance at Mar. 31, 2010	$ 95,728,000	$ 90,217,000	$ 3,000	$ (218,323,000)	$ 223,831,000
Beginning balance, shares at Mar. 31, 2010			25,801,690	(13,775,188)
Stock issued under employee stock purchase plan, shares			7,073
Stock issued under employee stock purchase plan	317,000	317,000
Stock issued under stock option plan, net of shares repurchased, shares			313,321
Stock issued under stock option plan, net of shares repurchased	4,728,000	4,728,000
Stock-based compensation expense	2,544,000	2,544,000
Income tax benefits from stock option exercises	2,267,000	2,267,000
Purchase of treasury stock, shares	(715,975)			(715,975)
Purchase of treasury stock	(30,608,000)			(30,608,000)
Net income	24,663,000				24,663,000
Ending balance at Mar. 31, 2011	99,639,000	100,073,000	3,000	(248,931,000)	248,494,000
Ending balance, shares at Mar. 31, 2011			26,122,084	(14,491,163)
Stock issued under employee stock purchase plan, shares			8,215
Stock issued under employee stock purchase plan	321,000	321,000
Stock issued under stock option plan, net of shares repurchased, shares			131,575
Stock issued under stock option plan, net of shares repurchased	2,241,000	2,241,000
Stock-based compensation expense	2,276,000	2,276,000
Income tax benefits from stock option exercises	996,000	996,000
Purchase of treasury stock, shares	(461,938)			(461,938)
Purchase of treasury stock	(21,643,000)			(21,643,000)
Net income	26,552,000				26,552,000
Ending balance at Mar. 31, 2012	110,382,000	105,907,000	3,000	(270,574,000)	275,046,000
Ending balance, shares at Mar. 31, 2012			26,261,874	(14,953,101)
Stock issued under employee stock purchase plan, shares	1,209,257		7,028
Stock issued under employee stock purchase plan	313,000	313,000
Stock issued under stock option plan, net of shares repurchased, shares			149,729
Stock issued under stock option plan, net of shares repurchased	3,399,000	3,399,000
Stock-based compensation expense	997,000	997,000
Income tax benefits from stock option exercises	308,000	308,000
Purchase of treasury stock, shares	(705,406)			(705,406)
Purchase of treasury stock	(30,727,000)			(30,727,000)
Net income	26,730,000				26,730,000
Ending balance at Mar. 31, 2013	$ 111,402,000	$ 110,924,000	$ 3,000	$ (301,301,000)	$ 301,776,000
Ending balance, shares at Mar. 31, 2013			26,418,631	(15,658,507)