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, 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 employee stock purchase plan	346,000		346,000
Stock issued under employee stock purchase plan, shares		2,636
Stock issued under stock option plan, net of shares repurchased	4,922,000		4,922,000
Stock issued under stock option plan, net of shares repurchased, shares		99,950
Stock-based compensation expense	4,027,000		4,027,000
Purchase of treasury stock	(75,081,000)			$ (75,081,000)
Purchase of treasury stock, shares				(491,493)
Net income	48,196,000				48,196,000
Ending balance at Dec. 31, 2022	194,805,000	$ 3,000	210,904,000	$ (729,601,000)	713,499,000
Ending balance, shares at Dec. 31, 2022		54,891,298		(37,711,118)
Beginning balance at Sep. 30, 2022	197,833,000	$ 3,000	207,986,000	$ (706,806,000)	696,650,000
Beginning balance, shares at Sep. 30, 2022		54,873,202		(37,559,016)
Stock issued under stock option plan, net of shares repurchased	1,220,000		1,220,000
Stock issued under stock option plan, net of shares repurchased, shares		18,096
Stock-based compensation expense	1,698,000		1,698,000
Purchase of treasury stock	(22,795,000)			$ (22,795,000)
Purchase of treasury stock, shares				(152,102)
Net income	16,849,000				16,849,000
Ending balance at Dec. 31, 2022	194,805,000	$ 3,000	210,904,000	$ (729,601,000)	713,499,000
Ending balance, shares at Dec. 31, 2022		54,891,298		(37,711,118)
Beginning balance at Mar. 31, 2023	202,176,000	$ 3,000	218,700,000	$ (748,195,000)	731,668,000
Beginning balance, shares at Mar. 31, 2023		54,987,366		(37,817,866)
Stock issued under employee stock purchase plan	336,000		336,000
Stock issued under employee stock purchase plan, shares		1,797
Stock issued under stock option plan, net of shares repurchased	7,059,000		7,059,000
Stock issued under stock option plan, net of shares repurchased, shares		105,505
Stock-based compensation expense	3,690,000		3,690,000
Purchase of treasury stock	(36,529,000)			$ (36,529,000)
Purchase of treasury stock, shares				(177,484)
Net income	56,798,000				56,798,000
Ending balance at Dec. 31, 2023	233,530,000	$ 3,000	229,785,000	$ (784,724,000)	788,466,000
Ending balance, shares at Dec. 31, 2023		55,094,668		(37,995,350)
Beginning balance at Sep. 30, 2023	222,569,000	$ 3,000	226,595,000	$ (775,400,000)	771,371,000
Beginning balance, shares at Sep. 30, 2023		55,070,842		(37,951,359)
Stock issued under stock option plan, net of shares repurchased	2,114,000		2,114,000
Stock issued under stock option plan, net of shares repurchased, shares		23,826
Stock-based compensation expense	1,076,000		1,076,000
Purchase of treasury stock	(9,324,000)			$ (9,324,000)
Purchase of treasury stock, shares				(43,991)
Net income	17,095,000				17,095,000
Ending balance at Dec. 31, 2023	$ 233,530,000	$ 3,000	$ 229,785,000	$ (784,724,000)	$ 788,466,000
Ending balance, shares at Dec. 31, 2023		55,094,668		(37,995,350)