Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Total	Cumulative Effect, Period of Adoption, Adjustment	Sale Of Business [Member]	Retained Earnings [Member]	Retained Earnings [Member] Cumulative Effect, Period of Adoption, Adjustment	Common Stock [Member]	AOCI Attributable to Parent [Member]	AOCI Attributable to Parent [Member] Sale Of Business [Member]	Additional Paid-in Capital [Member]
Beginning balance at Mar. 31, 2019	$ 1,209,487			$ 1,212,352		$ 451	$ (3,316)
Net Earnings	70,894			70,894
Stock Option Exercises and Restricted Share Vesting	3,299					1			$ 3,298
Purchase and Retirement of Common Stock	313,887			305,737		36			8,114
Dividends to Stockholders	(16,808)			16,808
Stock Compensation Expense	19,822								19,822
Shares Redeemed to Settle Employee Taxes	(4,063)								4,063
Unfunded Pension Liability, net of tax	(265)						(265)
Ending Balance at Mar. 31, 2020	967,843	$ (636)		960,065	$ (636)	416	(3,581)		10,943
Net Earnings	339,444			339,444
Stock Option Exercises and Restricted Share Vesting	40,457					8			40,449
Stock Compensation Expense	15,291								15,291
Shares Redeemed to Settle Employee Taxes	(4,186)								4,186
Unfunded Pension Liability, net of tax	(113)		$ 254				(113)	$ 254
Ending Balance at Mar. 31, 2021	1,358,990			1,299,509		424	(3,440)		62,497
Net Earnings	374,247			374,247
Stock Option Exercises and Restricted Share Vesting	21,366					3			21,363
Purchase and Retirement of Common Stock	589,742			496,886		40			92,816
Dividends to Stockholders	(40,526)			40,526
Stock Compensation Expense	14,264								14,264
Shares Redeemed to Settle Employee Taxes	(5,308)								$ 5,308
Unfunded Pension Liability, net of tax	265						265
Ending Balance at Mar. 31, 2022	$ 1,133,556			$ 1,136,344		$ 387	$ (3,175)