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	27,000
Issuance of restricted stock awards	$ 1	0	0	0	0	1
Issuance of restricted stock awards (in shares)	182
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)			(76)
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	27,106
Balance at Mar. 31, 2020	$ 144	145,197	(68,424)	410,219	(991)	486,145
Balance (in shares) at Mar. 31, 2020	27,000
Net earnings						58,844
Balance at Dec. 31, 2020	$ 145	150,624	(75,372)	469,063	549	545,009
Balance (in shares) at Dec. 31, 2020	27,006
Balance at Jun. 30, 2020	$ 145	147,082	(71,127)	427,579	(954)	502,725
Balance (in shares) at Jun. 30, 2020	27,106
Issuance of restricted stock awards	$ 0	0	0	0	0	0
Issuance of restricted stock awards (in shares)	16
Share-based compensation	$ 0	1,763	0	0	0	1,763
Share-based compensation (in shares)	0
Repurchase of common stock	$ 0	0	$ (1,784)	0	0	(1,784)
Repurchase of common stock (in shares)			(48)
Net earnings	0	0	$ 0	19,846	0	19,846
Foreign currency translation adjustment	0	0	0	0	520	520
Balance at Sep. 30, 2020	$ 145	148,845	(72,911)	447,425	(434)	523,070
Balance (in shares) at Sep. 30, 2020	27,074
Issuance of restricted stock awards	$ 0	0	0	0	0	0
Issuance of restricted stock awards (in shares)	2
Share-based compensation	$ 0	1,779	0	0	0	1,779
Share-based compensation (in shares)	0
Repurchase of common stock	$ 0	0	$ (2,461)	0	0	(2,461)
Repurchase of common stock (in shares)			(70)
Net earnings	0	0	$ 0	21,638	0	21,638
Foreign currency translation adjustment	0	0	0	0	983	983
Balance at Dec. 31, 2020	$ 145	150,624	(75,372)	469,063	549	545,009
Balance (in shares) at Dec. 31, 2020	27,006
Balance at Mar. 31, 2021	$ 145	152,366	(75,372)	484,616	655	$ 562,410
Balance (in shares) at Mar. 31, 2021	27,006					27,006
Issuance of restricted stock awards	$ 1	0	0	0	0	$ 1
Issuance of restricted stock awards (in shares)	156
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)			(90)
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	27,072
Balance at Mar. 31, 2021	$ 145	152,366	(75,372)	484,616	655	$ 562,410
Balance (in shares) at Mar. 31, 2021	27,006					27,006
Net earnings						$ 81,355
Balance at Dec. 31, 2021	$ 270	157,721	(2,592)	483,601	296	$ 639,296
Balance (in shares) at Dec. 31, 2021	26,966					26,966
Balance at Jun. 30, 2021	$ 146	154,101	(79,483)	508,134	721	$ 583,619
Balance (in shares) at Jun. 30, 2021	27,072
Issuance of restricted stock awards	$ 0	0	0	0	0	0
Issuance of restricted stock awards (in shares)	12
Share-based compensation	$ 0	1,840	0	0	0	1,840
Share-based compensation (in shares)	0
Repurchase of common stock	$ 0	0	$ (2,763)	0	0	(2,763)
Repurchase of common stock (in shares)			(63)
Net earnings	0	0	$ 0	31,413	0	31,413
Foreign currency translation adjustment	0	0	0	0	(506)	(506)
Balance at Sep. 30, 2021	$ 146	155,941	(82,246)	539,547	215	613,603
Balance (in shares) at Sep. 30, 2021	27,021
Issuance of restricted stock awards	$ 0	0	0	0	0	0
Issuance of restricted stock awards (in shares)	(5)
Share-based compensation	$ 0	1,780	0	0	0	1,780
Share-based compensation (in shares)	0
Repurchase of common stock	$ 0	0	$ (2,592)	0	0	(2,592)
Repurchase of common stock (in shares)			(50)
Stock split effected in the form of a dividend	135	0	$ 0	(135)	0	0
Retirement of treasury stock	(11)	0	82,246	(82,235)	0	0
Net earnings	0	0	0	26,424	0	26,424
Foreign currency translation adjustment	0	0	0	0	81	81
Balance at Dec. 31, 2021	$ 270	$ 157,721	$ (2,592)	$ 483,601	$ 296	$ 639,296
Balance (in shares) at Dec. 31, 2021	26,966					26,966