PENSION AND POSTRETIREMENT BENEFITS (Contributions in the Aggregate) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
May 25, 2014	May 26, 2013	May 27, 2012
Plans not individually significant
Multiemployer plans, plan contributions	$ 12.4	$ 9.4	$ 8.5
Bakery and Confectionary Union and Industry International Pension Plan
Plans not individually significant
Entity tax identification number	526118572
Multiemployer plan number	001
Multiemployer plans, certified zone status	Red
Multiemployer plans, funding improvement plan and rehabilitation plan	Implemented
Multiemployer plans, plan contributions	3.5	2.1	1.3
Multiemployer plans, surcharge	No
Multiemployer plans, collective-bargaining arrangement, expiration date, description	12/08/2012 to 7/23/2016
Central States, Southeast and Southwest Areas Pension Fund
Plans not individually significant
Entity tax identification number	366044243
Multiemployer plan number	001
Multiemployer plans, certified zone status	Red
Multiemployer plans, funding improvement plan and rehabilitation plan	Implemented
Multiemployer plans, plan contributions	2.1	1.2	1.2
Multiemployer plans, surcharge	No
Multiemployer plans, collective-bargaining arrangement, expiration date, description	06/02/2014 to 06/04/2017
National Conference of Fireman and Oilers National Pension Fund
Plans not individually significant
Entity tax identification number	526085445
Multiemployer plan number	003
Multiemployer plans, certified zone status	Yellow
Multiemployer plans, funding improvement plan and rehabilitation plan	Implemented
Multiemployer plans, plan contributions	0.7	0.3	0
Multiemployer plans, surcharge	No
Multiemployer plans, collective-bargaining arrangement, expiration date, description	11/19/2015
Western Conference of Teamsters Pension Plan
Plans not individually significant
Entity tax identification number	916145047
Multiemployer plan number	001
Multiemployer plans, certified zone status	Green
Multiemployer plans, funding improvement plan and rehabilitation plan	NA
Multiemployer plans, plan contributions	4.9	4.9	5.2
Multiemployer plans, surcharge	No
Multiemployer plans, collective-bargaining arrangement, expiration date, description	06/30/2015 to 03/31/2018
Other Plans
Plans not individually significant
Multiemployer plans, plan contributions	$ 1.2	$ 0.9	$ 0.8

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The Tax Identification Number (TIN), also known as an Employer Identification Number (EIN), is a unique 9-digit value assigned by the IRS.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation 12B

-Number 240

-Section 12b

-Subsection 1

+ Details

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- Definition

Three digit plan number for a pension or postretirement benefit plan to which two or more unrelated employers contribute where assets contributed by one participating employer may be used to provide benefits to employees of other participating employers.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 80

-Section 50

-Paragraph 5

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=14450570&loc=SL14450657-114947

+ Details

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- Definition

Indicate the multiemployer plan's certified zone status as currently required by the Pension Protection Act of 2006 or a subsequent amendment thereof. The zone status categories are red (critical status), orange (seriously endangered), yellow (endangered), and green (none of the above). The acceptable values are "red", "orange", "yellow", "green", "other", and "NA". A multiemployer plan is a pension or postretirement benefit plan to which two or more unrelated employers contribute where assets contributed by one participating employer may be used to provide benefits to employees of other participating employers.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 80

-Section 50

-Paragraph 5

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=14450570&loc=SL14450657-114947

+ Details

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- Definition

Description of the significant collective-bargaining arrangements within the range of expiration dates for collective-bargaining arrangements requiring contributions to a multiemployer plan as well as other information to help investors understand the significance of the collective-bargaining agreements and when they expire. A multiemployer plan is a pension or postretirement benefit plan to which two or more unrelated employers contribute where assets contributed by one participating employer may be used to provide benefits to employees of other participating employers.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 80

-Section 50

-Paragraph 5

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=14450570&loc=SL14450657-114947

+ Details

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- Definition

Indicate whether a funding improvement plan or rehabilitation plan has been implemented or is pending for a pension or postretirement benefit plan to which two or more unrelated employers contribute where assets contributed by one participating employer may be used to provide benefits to employees of other participating employers. The acceptable values are "no", "pending", "implemented", "other", and "NA".

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 80

-Section 50

-Paragraph 5

-Subparagraph (f)(1)

-URI http://asc.fasb.org/extlink&oid=14450570&loc=SL14450657-114947

+ Details

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- Definition

Amount of contributions made to the multiemployer plan by all employers who participate in the plan. A multiemployer plan is a pension or postretirement benefit plan to which two or more unrelated employers contribute where assets contributed by one participating employer may be used to provide benefits to employees of other participating employers.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 80

-Section 50

-Paragraph 7

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=14450570&loc=SL14450678-114947

+ Details

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- Definition

Indicate whether the employer paid a surcharge to the pension or postretirement benefit plan to which two or more unrelated employers contribute where assets contributed by one participating employer may be used to provide benefits to employees of other participating employers. The acceptable values are "no", "yes", and "NA".

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 80

-Section 50

-Paragraph 5

-Subparagraph (f)(2)

-URI http://asc.fasb.org/extlink&oid=14450570&loc=SL14450657-114947

+ Details

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