FAIR VALUE MEASUREMENTS - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
Aug. 30, 2020	Aug. 25, 2019	May 31, 2020
Goodwill [Line Items]
Asset impairment charges	$ 3.4	$ 67.0
Carrying amount of long-term debt (including current installments)	9,620.0		$ 9,750.0
Estimated fair value of debt	11,380.0		$ 11,350.0
Grocery & Snacks
Goodwill [Line Items]
Asset impairment charges	$ 3.0	43.3
Indefinite-lived brand impairment charges		3.5
Refrigerated & Frozen
Goodwill [Line Items]
Indefinite-lived brand impairment charges		$ 15.8

Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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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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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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