Note 1 - Organization, Basis of Presentation, and Summary of Significant Accounting Policies - Significant Unobservable Inputs Used in Discounted Cash Flow Models (Details)	9 Months Ended	12 Months Ended
Feb. 25, 2018	May 28, 2017
Revenue growth rates	6.00%	4.00%
Expense growth rates		4.00%
Income tax rates	15.00%	15.00%
Discount rates	12.00%	12.00%
Minimum [Member]
Revenue growth rates
Expense growth rates	5.00%
Income tax rates
Discount rates
Maximum [Member]
Revenue growth rates
Expense growth rates	6.00%
Income tax rates
Discount rates

Interest rate used to find the present value of an amount to be paid or received in the future as an input to measure fair value. For example, but not limited to, weighted average cost of capital (WACC), cost of capital, cost of equity and cost of debt.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration