Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2021	Mar. 31, 2020
Statement Of Financial Position [Abstract]
Allowance for doubtful accounts receivable	$ 1,220	$ 1,634
Common stock, stated value	$ 0.30	$ 0.30
Common stock, shares authorized	80,000,000	80,000,000
Common stock, shares issued	31,606,831	31,606,831
Common stock, shares outstanding	24,010,727	23,609,398
Treasury shares	7,596,104	7,997,433