Note 6 - Acquisitions - Allocation of the Purchase Price for Acquisitions (Details) (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Oct. 31, 2014
Liabilities assumed:
Goodwill and other intangible assets	$ 127,031
Total consideration paid, net of cash acquired	34,288
In Fiscal Year 2015 [Member]
Assets acquired:
Inventories	2,471
Property and equipment	25,250
Total assets	27,721
Liabilities assumed:
Accrued expenses	58
Total liabilities	27,663
Goodwill and other intangible assets	6,625
Total consideration paid, net of cash acquired	$ 34,288