PENSION AND POSTRETIREMENT BENEFITS (Contributions in the Aggregate) (Details) - USD ($) $ in Millions	12 Months Ended
May. 31, 2015	May. 25, 2014	May. 26, 2013
Multiemployer Plans [Line Items]
Contributions by the Company	$ 12.0	$ 12.4	$ 9.4
Bakery and Confectionary Union and Industry International Pension Plan
Multiemployer Plans [Line Items]
EIN	526118572
PN	001
Pension Protection Act Zone Status		Red	Red
FIP / RP Status Pending / Implemented	Implemented
Contributions by the Company	$ 3.7	$ 3.5	$ 2.1
Surcharge Imposed	No
Expiration Dates of Collective Bargaining Agreements	2/29/2016 to 5/18/2018
Central States, Southeast and Southwest Areas Pension Fund
Multiemployer Plans [Line Items]
EIN	366044243
PN	001
Pension Protection Act Zone Status		Red	Red
FIP / RP Status Pending / Implemented	Implemented
Contributions by the Company	$ 2.0	$ 2.1	$ 1.2
Surcharge Imposed	No
Expiration Dates of Collective Bargaining Agreements	6/30/2015 to 6/04/2017
National Conference of Fireman & Oilers National Pension Fund
Multiemployer Plans [Line Items]
EIN	526085445
PN	003
Pension Protection Act Zone Status		Yellow	Yellow
FIP / RP Status Pending / Implemented	Implemented
Contributions by the Company	$ 0.6	$ 0.7	$ 0.3
Surcharge Imposed	No
Expiration Dates of Collective Bargaining Agreements	11/19/2015
Western Conference of Teamsters Pension Plan
Multiemployer Plans [Line Items]
EIN	916145047
PN	001
Pension Protection Act Zone Status		Green	Green
FIP / RP Status Pending / Implemented	NA
Contributions by the Company	$ 4.9	$ 4.9	$ 4.9
Surcharge Imposed	No
Expiration Dates of Collective Bargaining Agreements	06/30/2015 to 03/31/2018
Other Plans
Multiemployer Plans [Line Items]
Contributions by the Company	$ 0.8	$ 1.2	$ 0.9

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

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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.

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-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 80

-Section 50

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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.

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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.

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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".

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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.

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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".

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