Note 10 - Stock-based Compensation (Details Textual) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Apr. 27, 2024	Apr. 29, 2023	Apr. 30, 2022
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Gross (in shares)	0	0	30,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value (in dollars per share)			$ 6.91
Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Term (Year)			6 years 6 months
Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Volatility Rate			20.74%
Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Risk Free Interest Rate			0.82%
Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Dividend Rate			2.48%
Share-Based Payment Arrangement, Expense	$ 900	$ 700	$ 700
Share-Based Payment Arrangement, Expense, Tax Benefit	1,700	200	400
Share-Based Payment Arrangement, Exercise of Option, Tax Benefit	1,500	100	300
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercises in Period, Intrinsic Value	9,100	400	1,400
Proceeds from Stock Options Exercised	1,314	$ 311	$ 335
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount	$ 1,400
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)	1 year 7 months 6 days
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term (Year)	5 years 4 months 24 days
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Intrinsic Value	$ 5,500
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term (Year)	4 years 8 months 12 days
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercisable, Intrinsic Value	$ 3,300
Omnibus Plan [Member]
Share Based Compensation Arrangement by Share Based Payment Award Number of Shares Authorized Per Individual (in shares)	3,360,000
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year)	5 years
Share-Based Compensation Arrangement by Share-Based Payment Award, Expiration Period (Year)	10 years
Omnibus Plan [Member] | Stock Options or Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized (in shares)	9,600,000
Omnibus Plan [Member] | SARS Dividend Equivalents and Other Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized (in shares)	9,600,000
Special Stock Option Plan [Member] | Determined by Board of Directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized (in shares)	3,600,000
Special Stock Option Plan [Member] | Share-Based Payment Arrangement, Option [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Expiration Period (Year)	10 years
Special Stock Option Plan [Member] | Determined By Chairman Member
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized (in shares)	100,000
KEEP Program [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized (in shares)	480,000
Share Based Compensation Arrangement by Share Based Payment Award Number of Shares Authorized Per Individual (in shares)	12,000
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year)	6 years
Share Based Compensation Arrangement by Share Based Payment Award Percentage of Purchased Shares Matched	50.00%
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants, Period (Year)	2 years
Share-based Compensation Arrangement by Share-based Payment Award, Purchase Price of Common Stock, Percent	60.00%
KEEP Program [Member] | Share-Based Payment Arrangement, Option [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Expiration Period (Year)	10 years