Retirement Plans - Summary Changes in Plan Assets and Benefit Obligations (Detail) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018
Retirement Benefits [Abstract]
Defined Benefit Plan, Amortization of Prior Service Cost (Credit)	$ 0	$ 0	$ 0
Changes in plan assets and benefit obligations:
Net loss (gain) arising during the year	3,793	(99)	(1,953)
Effect of exchange rates on amounts included in AOCI	(804)	(1,984)	3,019
Amounts recognized as a component of net periodic benefit costs:
Amortization of prior service cost	(43)	(45)	(46)
Amortization or settlement recognition of net loss	(1,250)	(1,659)	(1,725)
Total recognized in other comprehensive income	$ 1,696	$ (3,787)	$ (705)