Condensed Consolidated Balance Sheets (Parenthetical) (Unaudited) - USD ($) $ in Thousands	Dec. 31, 2018	Mar. 31, 2018
Statement of Financial Position [Abstract]
Allowance for doubtful accounts receivable	$ 839	$ 900
Accounts receivable, net	$ 33,640	$ 16,389
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	23,535,090	23,324,679
Treasury shares	8,071,741	8,282,152