Note 12 - Fair Value Measurements - Losses Recognized from Fair Value Measurement on Non-recurring Basis (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Feb. 28, 2017	Mar. 01, 2016	Feb. 28, 2017	Mar. 01, 2016
Long-lived asset impairments			$ 32,668	$ 17,489
Closure and Impairments [Member]
Long-lived assets held for use	$ 14,914	$ 6,764	29,930	15,206
Long-lived assets held for sale	32	174	2,844	524
Lime Fresh trademark				1,999
Long-lived asset impairments	$ 14,946	$ 6,938	$ 32,774	$ 17,729

Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 45
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=68055307&loc=d3e2420-110228

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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Total loss recognized during the period from the impairment of goodwill plus the loss recognized in the period resulting from the impairment of the carrying amount of intangible assets, other than goodwill.

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
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