Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Mar. 31, 2021
Statement of Comprehensive Income [Abstract]
Net income	$ 59,648	$ 35,874	$ 19,352
Other comprehensive income:
Cumulative translation adjustments	(270)	153	2,926
Recognition of actuarial net gains (losses) from pension and other post-retirement plans, net of tax (benefit) of $2,448, $824, and ($657)	5,759	1,937	(1,548)
Changes in market value of investments:
Changes in unrealized gains (losses), net of tax (benefit) of $14, ($9), and ($41)	42	(29)	(130)
Total net change in market value of investments	42	(29)	(130)
Changes in market value of derivatives:
Changes in market value of derivatives, net of (benefit) tax of ($116), $19, and $66	(361)	63	208
Reclassification adjustment for net gain (loss) included in net income, net of tax (benefit) of $137, ($13), and ($73)	427	(43)	(236)
Total net change in market value of derivatives	66	20	(28)
Other comprehensive income	5,597	2,081	1,220
Total comprehensive income	$ 65,245	$ 37,955	$ 20,572