UNAUDITED CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Net sales
Total	$ 433,081	$ 411,565	$ 788,112	$ 792,937
Cost of sales
Total	334,119	308,534	590,593	597,267
Gross profit	98,962	103,031	197,519	195,670
Selling, general, and administrative	66,889	70,523	136,356	136,310
Depreciation and amortization	3,341	3,557	6,857	7,020
Interest and financing costs	247	576	824	1,204
Operating expenses	70,477	74,656	144,037	144,534
Operating income	28,485	28,375	53,482	51,136
Other income (expense)	184	(40)	282	(85)
Earnings before tax	28,669	28,335	53,764	51,051
Provision for income taxes	8,823	8,237	16,558	14,765
Net earnings	$ 19,846	$ 20,098	$ 37,206	$ 36,286
Net earnings per common share-basic (in dollars per share)	$ 1.48	$ 1.51	$ 2.79	$ 2.72
Net earnings per common share-diluted (in dollars per share)	$ 1.48	$ 1.51	$ 2.78	$ 2.71
Weighted average common shares outstanding-basic (in shares)	13,372	13,312	13,347	13,334
Weighted average common shares outstanding-diluted (in shares)	13,391	13,350	13,394	13,408
Product [Member]
Net sales
Total	$ 383,656	$ 363,497	$ 690,896	$ 699,098
Cost of sales
Total	302,963	278,863	529,597	538,926
Services [Member]
Net sales
Total	49,425	48,068	97,216	93,839
Cost of sales
Total	$ 31,156	$ 29,671	$ 60,996	$ 58,341