PENSION AND POSTRETIREMENT BENEFITS - Schedule of Contributions for Plans That Are Not Individually Significant (Details) - USD ($) $ in Millions	12 Months Ended
May 30, 2021	May 31, 2020	May 26, 2019
Multiemployer Plans [Line Items]
Entity Tax Identification Number	47-0248710
Total Contributions	$ 7.4	$ 6.5	$ 6.0
Bakery and Confectionary Union and Industry International Pension Plan
Multiemployer Plans [Line Items]
Entity Tax Identification Number	52-6118572
PN	001
Pension Protection Act Zone Status		Red	Red
FIP / RP Status	Implemented
Total Contributions	$ 0.0	$ 0.0	$ 0.1
Surcharge Imposed	No
Central States, Southeast and Southwest Areas Pension Fund
Multiemployer Plans [Line Items]
Entity Tax Identification Number	36-6044243
PN	001
Pension Protection Act Zone Status		Red	Red
FIP / RP Status	Implemented
Total Contributions	$ 2.2	$ 2.0	$ 1.8
Surcharge Imposed	No
Expiration Dates of Collective Bargaining Agreements	May 31, 2021
Western Conference of Teamsters Pension Plan
Multiemployer Plans [Line Items]
Entity Tax Identification Number	91-6145047
PN	001
Pension Protection Act Zone Status		Green	Green
FIP / RP Status	NA
Total Contributions	$ 3.8	$ 3.2	$ 3.2
Surcharge Imposed	No
Expiration Dates of Collective Bargaining Agreements	Jun. 30, 2022
Other Plans
Multiemployer Plans [Line Items]
Total Contributions	$ 1.4	$ 1.3	$ 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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-Publisher SEC
-Name Regulation 12B
-Number 240
-Section 12
-Subsection b-2

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Indicates certified zone status of multiemployer pension plan determined to be individually significant. Acceptable values are "Green", "Yellow", "Orange", "Red", "Other", and "NA".

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- Definition

Expiration date of collective-bargaining arrangement (CBA) requiring contribution to multiemployer pension plan determined to be individually significant, in CCYY-MM-DD format.

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- Definition

Indicates whether funding improvement plan or rehabilitation plan was implemented or pending for multiemployer pension plan, determined to be individually significant. Acceptable values are "No", "Pending", "Implemented", "Other", and "NA".

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Amount of contribution received by multiemployer pension plan from all employers participating in multiemployer pension plan determined to be individually significant.

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Plan number for multiemployer pension plan determined to be individually significant, in three-digit numeric format.

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Indicates whether employer paid surcharge to multiemployer pension plan determined to be individually significant. Acceptable values are "No", "Yes" and "NA".

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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.

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