Note 8 - Income Taxes - Unrecognized Tax Benefits (Details) - USD ($)	12 Months Ended
May. 31, 2015	May. 25, 2014	May. 26, 2013
Unrecognized tax benefits – beginning of the period	$ 1,035,000	$ 998,000	$ 766,000
Gross increases – tax positions in prior period	17,000	7,000	$ 103,000
Gross decreases – tax positions in prior period	(141,000)	(48,000)
Gross increases – current-period tax positions	$ 76,000	$ 78,000	$ 129,000
Lapse of statute of limitations
Unrecognized tax benefits – end of the period	$ 987,000	$ 1,035,000	$ 998,000

Amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 15A

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6907707&loc=SL6600010-109319

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Unrecognized Tax Benefit

-URI http://asc.fasb.org/extlink&oid=6527854

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Amount of decrease in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.

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Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations.

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