Consolidated Statements of Stockholders' Equity - USD ($)	Total	Common Stock [Member]	Paid-in Capital [Member]	Treasury Stock [Member]	Retained Earnings [Member]
Beginning balance at Mar. 31, 2020	$ 189,711,000	$ 3,000	$ 168,935,000	$ (531,764,000)	$ 552,537,000
Beginning balance, shares at Mar. 31, 2020		54,254,557		(36,285,591)
Stock issued under employee stock purchase plan	534,000	$ 0	534,000	$ 0	0
Stock issued under employee stock purchase plan, shares		6,007
Stock issued under stock option plan, net of shares repurchased	11,494,000	$ 0	11,494,000	0	0
Stock issued under stock option plan, net of shares repurchased, shares		269,078
Stock-based compensation expense	4,978,000	$ 0	4,978,000	0	0
Purchase of treasury stock	$ (32,671,000)	$ 0	0	$ (32,671,000)	0
Purchase of treasury stock, shares	(367,961)	0		(367,961)
Net income	$ 46,356,000	$ 0	0	$ 0	46,356,000
Ending balance at Mar. 31, 2021	220,402,000	$ 3,000	185,941,000	$ (564,435,000)	598,893,000
Ending balance, shares at Mar. 31, 2021		54,529,642		(36,653,552)
Stock issued under employee stock purchase plan	564,000	$ 0	564,000	$ 0	0
Stock issued under employee stock purchase plan, shares		3,363
Stock issued under stock option plan, net of shares repurchased	9,906,000	$ 0	9,906,000	0	0
Stock issued under stock option plan, net of shares repurchased, shares		255,707
Stock-based compensation expense	5,198,000	$ 0	5,198,000	0	0
Purchase of treasury stock	$ (90,085,000)	$ 0	0	$ (90,085,000)	0
Purchase of treasury stock, shares	(566,073)	0		(566,073)
Net income	$ 66,410,000	$ 0	0	$ 0	66,410,000
Ending balance at Mar. 31, 2022	212,395,000	$ 3,000	201,609,000	$ (654,520,000)	665,303,000
Ending balance, shares at Mar. 31, 2022		54,788,712		(37,219,625)
Stock issued under employee stock purchase plan	$ 676,000	$ 0	676,000	$ 0	0
Stock issued under employee stock purchase plan, shares	2,500,392	4,457
Stock issued under stock option plan, net of shares repurchased	$ 10,856,000	$ 0	10,856,000	0	0
Stock issued under stock option plan, net of shares repurchased, shares		194,197
Stock-based compensation expense	5,559,000	$ 0	5,559,000	0	0
Purchase of treasury stock	$ (93,675,000)	$ 0	0	$ (93,675,000)	0
Purchase of treasury stock, shares	(598,241)	0		(598,241)
Net income	$ 66,365,000	$ 0	0	$ 0	66,365,000
Ending balance at Mar. 31, 2023	$ 202,176,000	$ 3,000	$ 218,700,000	$ (748,195,000)	$ 731,668,000
Ending balance, shares at Mar. 31, 2023		54,987,366		(37,817,866)