UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - 9 months ended Dec. 31, 2017 - USD ($) shares in Thousands, $ in Thousands	Common Stock [Member]	Additional Paid-in Capital [Member]	Treasury Stock [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income [Member]	Total
Balance at Mar. 31, 2017	$ 142	$ 123,536	$ 0	$ 222,823	$ (583)	$ 345,918
Balance (in shares) at Mar. 31, 2017	14,161					14,161
Issuance of restricted stock awards	$ 0	0	0	0	0	$ 0
Issuance of restricted stock awards (in shares)	68
Share-based compensation	$ 0	4,856	0	0	0	4,856
Repurchase of common stock	$ 0	0	(14,165)	0	0	(14,165)
Repurchase of common stock (in shares)	(183)
Net earnings	$ 0	0	0	46,225	0	46,225
Foreign currency translation adjustment	0	0	0	0	778	778
Balance at Dec. 31, 2017	$ 142	$ 128,392	$ (14,165)	$ 269,048	$ 195	$ 383,612
Balance (in shares) at Dec. 31, 2017	14,046					14,046