Note 5 - Derivative Financial Instruments (Details Textual) - USD ($)	Oct. 29, 2016	Apr. 30, 2016
Prepaid Expenses and Other Current Assets [Member]
Derivative Asset, Current	$ 159,000
Other Noncurrent Assets [Member]
Derivative Asset, Noncurrent	27,000
Accrued Liabilities1 [Member]
Derivative Liability, Current	676,000	$ 2,500,000
Derivative, Notional Amount	6,500,000
Price Risk Cash Flow Hedge Unrealized Gain (Loss) to be Reclassified During Next 12 Months	$ (517,000)