Note 6 - Capital Stock and Transactions With Related Parties (Details Textual) - USD ($) $ / shares in Units, $ in Thousands			12 Months Ended				388 Months Ended
	Dec. 29, 2021	Jan. 29, 2021	Apr. 30, 2023	Apr. 29, 2023	Apr. 30, 2022	May 01, 2021	Apr. 30, 2023
Statement [Line Items]
Payments of Ordinary Dividends, Common Stock	$ 280,000	$ 280,000		$ (0)	$ 280,003	$ 279,876
Common Stock, Dividends, Per Share, Cash Paid (in dollars per share)	$ 3.00	$ 3.00
CMA [Member]
Statement [Line Items]
Averaged Operating Costs			$ 800
Averaged Lease Buy-down Payments and Financing Costs			350
Related Party Transaction, Amounts of Transaction			11,700		11,400	$ 10,700
Accounts Payable			$ 2,900		$ 4,000		$ 2,900
CMA [Member] | Annual Fee Agreement Based on Percentage of Consolidated Net Sales [Member]
Statement [Line Items]
Related Party Transaction, Rate			1.00%
Payment for Incentive Fee							$ 0