Note 7 - Reconciliation of Income Tax Rate (Details)	12 Months Ended
Apr. 30, 2016	May 02, 2015	May 03, 2014
Statutory federal income tax rate	35.00%	35.00%	35.00%
State income taxes, net of federal benefit	2.20%	2.30%	2.30%
Domestic manufacturing deduction benefit	(3.00%)	(3.00%)	(3.00%)
Adjustment of unrecognized tax benefit	(0.10%)	(0.20%)	(3.30%)
Other differences	(0.10%)	(0.10%)	(0.10%)
Effective income tax rate	34.00%	34.00%	30.90%

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Section 50
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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 deduction for qualified production activity.

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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 applicable to state and local income tax expense (benefit), net of federal tax expense (benefit).

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