Note 6 - Leases (Details Textual) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Oct. 30, 2021	Oct. 31, 2020	Oct. 30, 2021	Oct. 31, 2020	May 01, 2021
Operating Lease, Cost	$ 3.6	$ 3.3	$ 7.3	$ 6.6
Operating Lease, Weighted Average Remaining Lease Term (Year)	4 years 3 months		4 years 3 months		3 years 21 days
Operating Lease, Weighted Average Discount Rate, Percent	3.08%		3.08%		3.38%
Operating Lease, Payments	$ 4.0	$ 3.5	$ 7.6	$ 7.0