PENSION AND POSTRETIREMENT BENEFITS (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended
Aug. 30, 2015	Aug. 24, 2014
Ardent Mills
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Special termination benefits expense		$ 6.9
Pension Benefits
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Employer contributions to pension plan and other postretirement plan	$ 2.8
Further contribution to pension and other postretirement plan	10.2
Postretirement Benefits
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Employer contributions to pension plan and other postretirement plan	5.0
Further contribution to pension and other postretirement plan	$ 18.7

Defined Benefit Plans, Estimated Future Employer Contributions in Remainder of Fiscal Year

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- Definition

The increase in the fair value of plan assets from contributions made by the employer.

+ 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 (b)(3)

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- Definition

If applicable, the cost of providing special or contractual termination benefits recognized during the period on the projected benefit obligation.

+ 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 (q)

-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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