Treasury Stock - Summary of Share Repurchases and Cumulatively Since Inception of Authorization (Detail) - USD ($)	12 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Mar. 31, 2022
Equity [Abstract]
Shares repurchased	215,313	598,241	566,073
Cost	$ 45,710,000	$ 93,675,000	$ 90,085,000
Average price	$ 212.29	$ 156.58	$ 159.14
Shares repurchased, Cumulative	38,033,179	37,817,866
Cost, Cumulative	$ 793,905,000
Average price, Cumulative	$ 20.87