Segment Information - Segment Information (Detail) (USD $)	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
Segment Reporting Information [Line Items]
Revenues from external customers	$ 27,052,000	$ 26,013,000	$ 26,098,000	$ 32,003,000	$ 31,803,000	$ 27,450,000	$ 31,185,000	$ 26,683,000	$ 111,166,000	$ 117,121,000	$ 102,847,000
Intersegment revenues									0
Depreciation									2,549,000	2,653,000	2,664,000
Earnings (loss) before income taxes									5,986,000	5,221,000	2,539,000
Income tax expense (benefit)									1,983,000	1,540,000	739,000
Net earnings attributable to noncontrolling interest	36,000	21,000	21,000	30,000	187,000	238,000	158,000	54,000	108,000	637,000	769,000
Net earnings (loss) attributable to Kewaunee Scientific Corporation	979,000	604,000	725,000	1,587,000	1,217,000	544,000	649,000	634,000	3,895,000	3,044,000	1,031,000
Segment assets	62,717,000				68,742,000				62,717,000	68,742,000	63,361,000
Expenditures for segment assets									2,021,000	2,405,000	1,435,000
Revenues (excluding intersegment) to customers in foreign countries									20,529,000	24,544,000	20,593,000
Corporate [Member]
Segment Reporting Information [Line Items]
Revenues from external customers									0
Intersegment revenues									(5,833,000)	(9,165,000)	(8,341,000)
Depreciation									0
Earnings (loss) before income taxes									(4,003,000)	(4,309,000)	(3,333,000)
Income tax expense (benefit)									(1,354,000)	(1,271,000)	(1,389,000)
Net earnings attributable to noncontrolling interest									0
Net earnings (loss) attributable to Kewaunee Scientific Corporation									(2,649,000)	(3,038,000)	(1,944,000)
Segment assets	0								0
Expenditures for segment assets									0
Revenues (excluding intersegment) to customers in foreign countries									0
Domestic Operations [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenues from external customers									91,750,000	93,519,000	83,971,000
Intersegment revenues									3,378,000	6,722,000	5,290,000
Depreciation									2,432,000	2,523,000	2,513,000
Earnings (loss) before income taxes									7,386,000	6,908,000	3,400,000
Income tax expense (benefit)									2,482,000	2,025,000	1,349,000
Net earnings attributable to noncontrolling interest									0
Net earnings (loss) attributable to Kewaunee Scientific Corporation									4,904,000	4,883,000	2,051,000
Segment assets	47,890,000				52,252,000				47,890,000	52,252,000	49,373,000
Expenditures for segment assets									1,822,000	2,314,000	1,395,000
Revenues (excluding intersegment) to customers in foreign countries									1,113,000	942,000	1,717,000
International Operations [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenues from external customers									19,416,000	23,602,000	18,876,000
Intersegment revenues									2,455,000	2,443,000	3,051,000
Depreciation									117,000	130,000	151,000
Earnings (loss) before income taxes									2,603,000	2,622,000	2,472,000
Income tax expense (benefit)									855,000	786,000	779,000
Net earnings attributable to noncontrolling interest									108,000	637,000	769,000
Net earnings (loss) attributable to Kewaunee Scientific Corporation									1,640,000	1,199,000	924,000
Segment assets	14,827,000				16,490,000				14,827,000	16,490,000	13,988,000
Expenditures for segment assets									199,000	91,000	40,000
Revenues (excluding intersegment) to customers in foreign countries									$ 19,416,000	$ 23,602,000	$ 18,876,000