Note 6 - Income Taxes (Details Textual) - USD ($)	3 Months Ended	12 Months Ended
Aug. 26, 2018	Aug. 27, 2017	May 27, 2018	May 28, 2017
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent	25.00%	37.00%	29.40%	35.00%
Income Tax Expense (Benefit), Total	$ 64,000	$ 1,310,000
Unrecognized Tax Benefits, Ending Balance	590,000		$ 479,000
Unrecognized Tax Benefits that Would Impact Effective Tax Rate	$ 515,000		$ 372,000

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

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

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Amount of unrecognized tax benefits.

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The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

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