Income Taxes - Schedule of Components of Provision for Income Taxes (Detail) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Mar. 31, 2022
Income Tax Disclosure [Abstract]
Current Provision - Federal	$ 111,690	$ 103,940	$ 87,626
Current Provision - State	20,689	18,520	6,924
Current Provision - Total	132,379	122,460	94,550
Deferred Provision (Benefit) - Federal	5,607	11,321	3,491
Deferred Provision (Benefit) - State	2,312	(6,728)	2,806
Deferred Provision (Benefit) - Total	7,919	4,593	6,297
Provision for Income Taxes	$ 140,298	$ 127,053	$ 100,847