Note 1 - Significant Accounting Policies - Allowance for Doubtful Accounts (Details) - USD ($) $ in Thousands	12 Months Ended
	Apr. 29, 2017	Apr. 30, 2016	May 02, 2015
Balance at beginning of year	$ 484	$ 330	$ 399
Net charge to expense	74	232	117
Net charge-off	(90)	(78)	(186)
Balance at end of year	$ 468	$ 484	$ 330