Stock Plans - Summary of Treasury Share Transactions Under the Company's Stock Repurchase Program (Details) - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Equity [Abstract]
Treasury shares at the beginning of period, Number of Shares	4,833	4,714
Treasury shares purchased, Number of Shares	112	119
Treasury shares at the end of period, Number of Shares	4,945	4,833
Treasury shares at the beginning of period, Amount	$ (71,438)	$ (70,459)
Treasury shares purchased, Amount	(905)	(979)
Treasury shares at the end of period, Amount	$ (72,343)	$ (71,438)