UNAUDITED CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2019	Dec. 31, 2018
Net sales
Total	$ 428,991	$ 345,664	$ 1,221,928	$ 1,047,239
Cost of sales
Total	325,295	262,751	922,562	798,123
Gross profit	103,696	82,913	299,366	249,116
Selling, general, and administrative	73,090	59,728	209,400	174,399
Depreciation and amortization	3,647	2,719	10,667	8,250
Interest and financing costs	694	443	1,898	1,403
Operating expenses	77,431	62,890	221,965	184,052
Operating income	26,265	20,023	77,401	65,064
Other income	997	721	912	1,140
Earnings before tax	27,262	20,744	78,313	66,204
Provision for income taxes	7,712	5,880	22,477	18,064
Net earnings	$ 19,550	$ 14,864	$ 55,836	$ 48,140
Net earnings per common share-basic (in dollars per share)	$ 1.47	$ 1.10	$ 4.19	$ 3.57
Net earnings per common share-diluted (in dollars per share)	$ 1.46	$ 1.10	$ 4.16	$ 3.54
Weighted average common shares outstanding-basic (in shares)	13,320	13,471	13,329	13,467
Weighted average common shares outstanding-diluted (in shares)	13,378	13,544	13,410	13,592
Product [Member]
Net sales
Total	$ 378,569	$ 310,443	$ 1,077,667	$ 942,735
Cost of sales
Total	293,209	241,856	832,135	735,802
Services [Member]
Net sales
Total	50,422	35,221	144,261	104,504
Cost of sales
Total	$ 32,086	$ 20,895	$ 90,427	$ 62,321