Note 8 - Stockholders' Equity (Details Textual) $ in Millions	3 Months Ended	6 Months Ended
Nov. 25, 2018 USD ($) shares	Nov. 25, 2018 USD ($) shares
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross	45,000	175,000
Common Stock, Capital Shares Reserved for Future Issuance	2,700,000	2,700,000
Stock Repurchase Program, Authorized Amount \| $	$ 10	$ 10
Treasury Stock, Shares, Acquired		0
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	19,000	254,000

Aggregate number of common shares reserved for future issuance.

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