CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (USD $) In Thousands, except Share data	Common Stock [Member]	Additional Paid-in Capital [Member]	Treasury Stock [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income [Member]	Total
Balance at Mar. 31, 2011	$ 125	$ 89,792	$ (45,998)	$ 167,539	$ 519	$ 211,977
Balance (in shares) at Mar. 31, 2011	8,519,000
Issuance of shares for option exercises and vesting of restricted shares	1	621	0	0	0	622
Issuance of shares for option exercises and vesting of restricted shares (in shares)	84,000
Excess tax benefit of share based compensation	0	740	0	0	0	740
Effect of share-based compensation, net of forfeitures	1	2,392	0	0	0	2,393
Effect of share-based compensation, net of forfeitures (in shares)	152,000
Purchase of treasury stock	0	0	(19,418)	0	0	(19,418)
Purchase of treasury stock (in shares)	(755,000)
Net earnings	0	0	0	23,367	0	23,367
Foreign currency translation adjustment	0	0	0	0	(54)	(54)
Balance at Mar. 31, 2012	127	93,545	(65,416)	190,906	465	219,627
Balance (in shares) at Mar. 31, 2012	8,000,000
Issuance of shares for option exercises and vesting of restricted shares	1	1,166	0	0	0	1,167
Issuance of shares for option exercises and vesting of restricted shares (in shares)	105,000
Excess tax benefit of share based compensation	0	1,648	0	0	0	1,648
Effect of share-based compensation, net of forfeitures	1	3,282	0	0	0	3,283
Effect of share-based compensation, net of forfeitures (in shares)	102,000
Purchase of treasury stock	0	0	(1,890)	0	0	(1,890)
Purchase of treasury stock (in shares)	(57,000)
Dividends declared	0	0	0	(20,378)	0	(20,378)
Net earnings	0	0	0	34,830	0	34,830
Foreign currency translation adjustment	0	0	0	0	(55)	(55)
Balance at Mar. 31, 2013	129	99,641	(67,306)	205,358	410	238,232
Balance (in shares) at Mar. 31, 2013	8,150,000					8,150,000
Issuance of shares for option exercises and vesting of restricted shares	0	559	0	0	0	559
Issuance of shares for option exercises and vesting of restricted shares (in shares)	40,000					40,000
Excess tax benefit of share based compensation	0	1,762	0	0	0	1,762
Issuance of restricted stock awards	1	0	0	0	0	1
Issuance of restricted stock awards (in shares)	87,000
Effect of share-based compensation, net of forfeitures		3,962	0	6	0	3,968
Purchase of treasury stock	0	0	(13,188)	0	0	(13,188)
Purchase of treasury stock (in shares)	(241,000)
Net earnings	0	0	0	35,273	0	35,273
Foreign currency translation adjustment	0	0	0	0	(224)	(224)
Balance at Mar. 31, 2014	$ 130	$ 105,924	$ (80,494)	$ 240,637	$ 186	$ 266,383
Balance (in shares) at Mar. 31, 2014	8,036,000					8,036,000