CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY (USD $) In Thousands, except Share data, unless otherwise specified	Total	Common Stock	Additional Paid-In Capital	Retained Earnings	Accumulated Other Comprehensive Income (Loss)	Comprehensive Income
BALANCE at Mar. 31, 2009	$ 250,464	$ 111	$ 163,131	$ 87,806	$ (584)
BALANCE (in shares) at Mar. 31, 2009		11,153,000
Increase (Decrease) in Shareholders' Equity
Net income	14,088			14,088		14,088
Other comprehensive income (loss) - currency translation adjustment, net of tax	1,910				1,910	1,910
Total comprehensive income	15,998					15,998
Exercise of stock options, including tax benefit	1,311	1	1,310
Exercise of stock options, including tax benefit (in shares)		58,000
Share-based compensation expense	5,031		5,031
Purchase of remaining interest in a consolidated subsidiary	(3,378)		(3,378)
BALANCE at Mar. 31, 2010	269,426	112	166,094	101,894	1,326
BALANCE (in shares) at Mar. 31, 2010		11,211,000
Increase (Decrease) in Shareholders' Equity
Net income	41,412			41,412		41,412
Other comprehensive income (loss) - currency translation adjustment, net of tax	1,388				1,388	1,388
Total comprehensive income	42,800					42,800
Exercise of stock options, including tax benefit	9,594	4	9,590
Exercise of stock options, including tax benefit (in shares)		417,000
Repurchase and retirement of common stock	(27,766)	(6)	(8,444)	(19,316)
Repurchase and retirement of common stock (in shares)		(556,000)
Share-based compensation expense	3,307		3,307
BALANCE at Mar. 31, 2011	297,361	110	170,547	123,990	2,714
BALANCE (in shares) at Mar. 31, 2011	11,072,053	11,072,000
Increase (Decrease) in Shareholders' Equity
Net income	14,102			14,102		14,102
Other comprehensive income (loss) - currency translation adjustment, net of tax	(861)				(861)	(861)
Total comprehensive income	13,241					13,241
Exercise of stock options, including tax benefit	4,251	2	4,249
Exercise of stock options, including tax benefit (in shares)		191,000
Repurchase and retirement of common stock	(43,802)	(10)	(15,532)	(28,260)
Repurchase and retirement of common stock (in shares)		(1,023,000)
Share-based compensation expense	2,650		2,650
BALANCE at Mar. 31, 2012	$ 273,701	$ 102	$ 161,914	$ 109,832	$ 1,853
BALANCE (in shares) at Mar. 31, 2012	10,239,819	10,240,000