Purchase of Noncontrolling Interest - Additional Information (Detail) (USD $)	3 Months Ended
	Jul. 31, 2013
Noncontrolling Interest [Line Items]
Total purchase price of minority ownership	$ 1,874,000
Cash paid to minority stock holders	1,780,000
Retained Earnings [Member]
Noncontrolling Interest [Line Items]
Total purchase price of minority ownership	1,874,000
Kewaunee Scientific Corporation India Pvt. Ltd. [Member]
Noncontrolling Interest [Line Items]
Minority owner ship percentage	49.00%
Total purchase price of minority ownership	3,555,000
Cash paid to minority stock holders	1,780,000
Other current liabilities recorded	887,500
Other non current liabilities recorded	887,500
Kewaunee Scientific Corporation India Pvt. Ltd. [Member] | Retained Earnings [Member]
Noncontrolling Interest [Line Items]
Total purchase price of minority ownership	1,874,000
Kewaunee Scientific Corporation India Pvt. Ltd. [Member] | Noncontrolling Interest [Member]
Noncontrolling Interest [Line Items]
Total purchase price of minority ownership	$ 1,681,000