INCOME TAXES - Effective Income Tax Rate Reconciliation (Details) - USD ($) $ in Thousands	12 Months Ended
Mar. 31, 2022	Mar. 31, 2021	Mar. 31, 2020
Effective Income Tax Rate Reconciliation, Amount
Federal income tax provision computed at statutory rate	$ 126,826	$ 85,937	$ 49,486
State and local taxes, net of federal tax effect	31,559	18,877	10,819
Tax impact from foreign operations	3,990	(1,036)	(1,083)
Nondeductible expenses	10,654	6,004	4,721
Stock compensation	(7,421)	(13,349)	(7,269)
Uncertain tax positions, true-up items, and other	6	24	(4,820)
Total	$ 165,614	$ 96,457	$ 51,854
Effective Income Tax Rate Reconciliation, Percent
Federal income tax provision computed at statutory rate	21.00%	21.00%	21.00%
State and local taxes, net of federal tax effect	5.20%	4.60%	4.60%
Tax impact from foreign operations	0.70%	(0.20%)	(0.50%)
Nondeductible expenses	1.80%	1.50%	2.00%
Stock compensation	(1.20%)	(3.30%)	(3.10%)
Uncertain tax positions, true-up items, and other	0.00%	0.00%	(2.00%)
Total	27.40%	23.60%	22.00%

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