Consolidated Quarterly Data (Unaudited) -Schedule of Quarterly Financial Information (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended								12 Months Ended
	Apr. 30, 2014	Jan. 31, 2014	Oct. 31, 2013	Jul. 31, 2013	Apr. 30, 2013	Jan. 31, 2013	Oct. 31, 2012	Jul. 31, 2012	Apr. 30, 2014	Apr. 30, 2013	Apr. 30, 2012
Quarterly Financial Information Disclosure [Abstract]
Net sales	$ 27,052	$ 26,013	$ 26,098	$ 32,003	$ 31,803	$ 27,450	$ 31,185	$ 26,683	$ 111,166	$ 117,121	$ 102,847
Gross profit	5,852	4,711	4,893	6,576	6,779	5,009	5,227	5,243	22,032	22,258	19,156
Net earnings	1,015	625	746	1,617	1,404	782	807	688	4,003	3,681	1,800
Less: net earnings attributable to the noncontrolling interest	36	21	21	30	187	238	158	54	108	637	769
Net earnings attributable to Kewaunee Scientific Corporation	$ 979	$ 604	$ 725	$ 1,587	$ 1,217	$ 544	$ 649	$ 634	$ 3,895	$ 3,044	$ 1,031
Net earnings per share attributable to Kewaunee Scientific Corporation
Basic	$ 0.37	$ 0.23	$ 0.28	$ 0.61	$ 0.47	$ 0.21	$ 0.25	$ 0.25	$ 1.49	$ 1.18	$ 0.40
Diluted	$ 0.37	$ 0.22	$ 0.28	$ 0.61	$ 0.46	$ 0.21	$ 0.25	$ 0.25	$ 1.48	$ 1.17	$ 0.40
Cash dividends per share	$ 0.11	$ 0.11	$ 0.11	$ 0.11	$ 0.10	$ 0.10	$ 0.10	$ 0.10