Consolidated Balance Sheets (Current Period Unaudited) (Parentheticals) (USD $) In Thousands, except Share data, unless otherwise specified	Nov. 30, 2014	May 25, 2014
Allowance for doubtful accounts	$ 415	$ 516
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, shares authorized (in shares)	50,000,000us-gaap_CommonStockSharesAuthorized	50,000,000us-gaap_CommonStockSharesAuthorized
Common stock, shares issued (in shares)	26,875,984us-gaap_CommonStockSharesIssued	26,815,253us-gaap_CommonStockSharesIssued
Common stock, shares outstanding (in shares)	26,875,984us-gaap_CommonStockSharesOutstanding	26,815,253us-gaap_CommonStockSharesOutstanding

A valuation allowance for trade and other receivables due to an Entity within one year (or the normal operating cycle, whichever is longer) that are expected to be uncollectible.

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