CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Mar. 31, 2019
Net sales
Total	$ 1,568,323	$ 1,588,404	$ 1,372,673
Cost of sales
Total	1,174,769	1,197,213	1,042,285
Gross profit	393,554	391,191	330,388
Selling, general, and administrative	271,263	279,182	237,082
Depreciation and amortization	13,951	14,156	11,824
Interest and financing costs	2,005	2,574	1,948
Operating expenses	287,219	295,912	250,854
Operating income	106,335	95,279	79,534
Other income (expense)	571	680	6,696
Earnings before tax	106,906	95,959	86,230
Provision for income taxes	32,509	26,877	23,038
Net earnings	$ 74,397	$ 69,082	$ 63,192
Net earnings per common share-basic (in dollars per share)	$ 5.58	$ 5.18	$ 4.70
Net earnings per common share-diluted (in dollars per share)	$ 5.54	$ 5.15	$ 4.65
Weighted average common shares outstanding-basic (in shares)	13,337	13,327	13,448
Weighted average common shares outstanding-diluted (in shares)	13,417	13,415	13,578
Product [Member]
Net sales
Total	$ 1,366,158	$ 1,395,288	$ 1,223,195
Cost of sales
Total	1,049,677	1,076,773	952,464
Services [Member]
Net sales
Total	202,165	193,116	149,478
Cost of sales
Total	$ 125,092	$ 120,440	$ 89,821