Retirement Benefits and Postemployment Benefits (Schedule of assumptions used to determine net periodic expense) (Details)	12 Months Ended
May 29, 2016	May 31, 2015	May 25, 2014
Defined Benefit Pension Plans [Member]
Defined Benefit Plan Weighted Average Assumptions Used In Calculating Net Periodic Benefit Cost Abstract
Discount rate	4.38%	4.54%	4.54%
Rate of salary increases	4.31%	4.44%	4.44%
Expected long-term rate of return on plan assets.	8.53%	8.53%	8.53%
Other Postretirement Benefit Plans [Member]
Defined Benefit Plan Weighted Average Assumptions Used In Calculating Net Periodic Benefit Cost Abstract
Discount rate	4.20%	4.51%	4.52%
Rate of salary increases	0.00%	0.00%	0.00%
Expected long-term rate of return on plan assets.	8.14%	8.13%	8.11%
Postemployment Benefit Plans [Member]
Defined Benefit Plan Weighted Average Assumptions Used In Calculating Net Periodic Benefit Cost Abstract
Discount rate	3.55%	3.82%	3.70%
Rate of salary increases	4.36%	4.44%	4.44%
Expected long-term rate of return on plan assets.	0.00%	0.00%	0.00%

The interest rate used to adjust for the time value of money.

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

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- Definition

An assumption as to the rate of return on plan assets reflecting the average rate of earnings expected on the funds invested or to be invested to provide for the benefits included in the benefit obligation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Expected Long-Term Rate of Return on Plan Assets
-URI http://asc.fasb.org/extlink&oid=6512046

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (k)(3)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920

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- Definition

Expected rate of compensation increases (for pay-related plans).

+ 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 (k)(2)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920

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- References

No definition available.

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