Note 8 - Employee Post-employment Benefits - Pension Plans with Benefit Obligations in Excess of Plan Assets (Details) - USD ($) $ in Thousands	Jun. 06, 2017	May 31, 2016
Pension Plan [Member]
Projected benefit obligation	$ 42,580	$ 44,429
Accumulated benefit obligation	42,580	44,428
Fair value of plan assets	6,126	6,209
Postretirement Medical and Life Benefits [Member]
Projected benefit obligation	989	1,100
Accumulated benefit obligation	989	1,100
Fair value of plan assets

Amount of accumulated benefit obligation for defined benefit pension plan with accumulated benefit obligation in excess of plan assets.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e2417-114920

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- Definition

Fair value of plan assets for defined benefit pension plan with accumulated benefit obligation in excess of plan assets.

+ References

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- Definition

Amount of projected benefit obligation for defined benefit pension plan with accumulated benefit obligation in excess of plan assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 55
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=77993564&loc=d3e4179-114921

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