Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Apr. 30, 2018	Apr. 30, 2017	Apr. 30, 2016
Income Statement [Abstract]
Net sales	$ 158,050	$ 138,558	$ 128,626
Costs of products sold	126,030	111,951	104,918
Gross profit	32,020	26,607	23,708
Operating expenses	22,934	20,065	18,010
Operating earnings	9,086	6,542	5,698
Other income, net	693	496	347
Interest expense	(299)	(292)	(306)
Earnings before income taxes	9,480	6,746	5,739
Income tax expense	4,115	2,126	1,862
Net earnings	5,365	4,620	3,877
Less: net earnings attributable to the noncontrolling interest	177	105	75
Net earnings attributable to Kewaunee Scientific Corporation	$ 5,188	$ 4,515	$ 3,802
Net earnings per share attributable to Kewaunee Scientific Corporation stockholders
Basic	$ 1.91	$ 1.67	$ 1.43
Diluted	$ 1.87	$ 1.66	$ 1.42
Weighted average number of common shares outstanding
Basic	2,720	2,705	2,667
Diluted	2,777	2,726	2,687