Note 8 - Income Taxes - Reconciliation of Income Tax Rate (Details)	12 Months Ended
May 01, 2021	May 02, 2020	Apr. 27, 2019
Statutory federal income tax rate	21.00%	21.00%	21.00%
State income taxes, net of federal benefit	2.90%	2.90%	2.90%
Domestic manufacturing deduction benefit	0.00%	0.00%	0.00%
Re-measurement of deferred taxes	0.00%	0.00%	0.00%
Other differences	(2.00%)	(6.00%)	(5.00%)
Effective income tax rate	23.70%	23.30%	23.40%

Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to changes in the income tax rates.

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