Retirement Benefits and Postemployment Benefits (Schedule of assumed health care trend costs) (Details)	12 Months Ended
May 29, 2016	May 31, 2015
Defined Benefit Plan Assumed Health Care Cost Trend Rates [Abstract]
Rate to which the cost trend rate is assumed to decline (ultimate rate)	5.00%	5.00%
Year that Rate Reaches Ultimate Trend Rate	2024	2025
Under Age 65 [Member]
Defined Benefit Plan Assumed Health Care Cost Trend Rates [Abstract]
Health care cost trend rate for next year	7.30%	6.50%
Over Age 65 [Member]
Defined Benefit Plan Assumed Health Care Cost Trend Rates [Abstract]
Health care cost trend rate for next year	7.50%	7.30%

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- Definition

The assumed health care cost trend rate for the next year used to measure the expected cost of benefits covered by the plan (gross eligible charges). This is based upon the annual rate of change in the cost of health care benefits currently provided by the postretirement benefit plan, due to factors other than changes in the composition of the plan population by age and dependency status.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Health Care Cost Trend Rate
-URI http://asc.fasb.org/extlink&oid=6514820

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (l)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920

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- Definition

The ultimate trend rate for health care costs.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (l)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920

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- Definition

Year the ultimate health care cost trend rate is expected to be reached, in CCYY format.

+ References

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