UNAUDITED CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - 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, 2020	$ 144	$ 145,197	$ (68,424)	$ 410,219	$ (991)	$ 486,145
Balance (in shares) at Mar. 31, 2020	13,500
Issuance of restricted stock awards	$ 1	0	0	0	0	1
Issuance of restricted stock awards (in shares)	91
Share-based compensation	$ 0	1,885	0	0	0	1,885
Share-based compensation (in shares)	0
Repurchase of common stock	$ 0	0	$ (2,703)	0	0	(2,703)
Repurchase of common stock (in shares)			(38)
Net earnings	0	0	$ 0	17,360	0	17,360
Foreign currency translation adjustment	0	0	0	0	37	37
Balance at Jun. 30, 2020	$ 145	147,082	(71,127)	427,579	(954)	502,725
Balance (in shares) at Jun. 30, 2020	13,553
Balance at Mar. 31, 2021	$ 145	152,366	(75,372)	484,616	655	$ 562,410
Balance (in shares) at Mar. 31, 2021	13,503					13,503
Issuance of restricted stock awards	$ 1	0	0	0	0	$ 1
Issuance of restricted stock awards (in shares)	78
Share-based compensation	$ 0	1,735	0	0	0	1,735
Share-based compensation (in shares)	0
Repurchase of common stock	$ 0	0	$ (4,111)	0	0	(4,111)
Repurchase of common stock (in shares)			(45)
Net earnings	0	0	$ 0	23,518	0	23,518
Foreign currency translation adjustment	0	0	0	0	66	66
Balance at Jun. 30, 2021	$ 146	$ 154,101	$ (79,483)	$ 508,134	$ 721	$ 583,619
Balance (in shares) at Jun. 30, 2021	13,536					13,536