CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - UNAUDITED - USD ($)	Total	Common Stock [Member]	Paid-in Capital [Member]	Treasury Stock [Member]	Retained Earnings [Member]
Beginning balance at Mar. 31, 2021	$ 220,402,000	$ 3,000	$ 185,941,000	$ (564,435,000)	$ 598,893,000
Beginning balance, shares at Mar. 31, 2021		54,529,642		(36,653,552)
Stock issued under stock option plan, net of shares repurchased	5,145,000	$ 0	5,145,000	$ 0	0
Stock issued under stock option plan, net of shares repurchased, shares		113,110		0
Stock-based compensation expense	1,345,000	$ 0	1,345,000	$ 0	0
Purchase of treasury stock	(14,196,000)	0	0	$ (14,196,000)	0
Purchase of treasury stock, shares				(118,893)
Net income	16,843,000	0	0	$ 0	16,843,000
Ending balance at Jun. 30, 2021	229,539,000	$ 3,000	192,431,000	$ (578,631,000)	615,736,000
Ending balance, shares at Jun. 30, 2021		54,642,752		(36,772,445)
Beginning balance at Mar. 31, 2022	212,395,000	$ 3,000	201,609,000	$ (654,520,000)	665,303,000
Beginning balance, shares at Mar. 31, 2022		54,788,712		(37,219,625)
Stock issued under stock option plan, net of shares repurchased	1,851,000	$ 0	1,851,000	$ 0	0
Stock issued under stock option plan, net of shares repurchased, shares		43,646		0
Stock-based compensation expense	1,379,000	$ 0	1,379,000	$ 0	0
Purchase of treasury stock	$ (26,688,000)	0	0	$ (26,688,000)	0
Purchase of treasury stock, shares	(174,882)			(174,882)
Net income	$ 16,691,000	0	0	$ 0	16,691,000
Ending balance at Jun. 30, 2022	$ 205,628,000	$ 3,000	$ 204,839,000	$ (681,208,000)	$ 681,994,000
Ending balance, shares at Jun. 30, 2022		54,832,358		(37,394,507)