GOODWILL AND OTHER IDENTIFIABLE INTANGIBLE ASSETS - Narrative (Details)	3 Months Ended
Aug. 30, 2020 USD ($) segment	Aug. 25, 2019 USD ($)
Goodwill [Line Items]
Fair value measurements discounted cash flow period	5 years
Remaining weighted average life of amortizing intangible assets	19 years
Amortization expense	$ 14,900,000	$ 15,000,000.0
Average amortization annual expense in year one	56,200,000
Average amortization annual expense in year two	56,200,000
Average amortization annual expense in year three	56,200,000
Average amortization annual expense in year four	56,200,000
Average amortization annual expense in year five	$ 56,200,000
Minimum
Goodwill [Line Items]
Fair value measurement inputs terminal growth rate	1.00%
Sides, Components, Enhancers
Goodwill [Line Items]
Fair value measurement inputs discount rate	6.25%
Refrigerated & Frozen
Goodwill [Line Items]
Number of reporting units \| segment	2
Goodwill impairment loss	$ 0
Impairment charges for indefinite lived intangibles		15,800,000
Refrigerated & Frozen \| Sides, Components, Enhancers \| Maximum
Goodwill [Line Items]
Percentage of fair value in excess of carrying value	20.00%
Refrigerated & Frozen and Grocery & Snacks \| Selling, general and administrative expenses \| Brands and Trademarks
Goodwill [Line Items]
Impairment charges for indefinite lived intangibles		$ 19,300,000

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Fair value measurement inputs terminal growth rate.

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Finite lived intangible assets average amortization expense next twelve months.

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Finite lived intangible assets average amortization expense year five.

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Finite lived intangible assets average amortization expense year four.

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Finite lived intangible assets average amortization expense year three.

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Finite lived intangible assets average amortization expense year two.

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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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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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Amount of impairment loss resulting from write-down of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit to fair value.

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Number of reporting units tested for impairment of goodwill. A reporting unit is an operating segment or one level below an operating segment.

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