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FAIR VALUE MEASUREMENTS - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Feb. 23, 2020	Nov. 24, 2019	May 31, 2020	May 26, 2019	May 27, 2018
Goodwill [Line Items]
Asset impairment charges			$ 259.9	$ 93.8	$ 14.7
Carrying amount of long-term debt (including current installments)			9,750.0	10,680.0
Estimated fair value of debt			11,350.0	11,240.0
Grocery & Snacks
Goodwill [Line Items]
Indefinite-lived brand impairment charges			46.4	76.5	4.0
Asset impairment charges			54.4
International
Goodwill [Line Items]
Indefinite-lived brand impairment charges			8.3	13.1	0.8
Refrigerated & Frozen
Goodwill [Line Items]
Indefinite-lived brand impairment charges			110.8
Asset impairment charges	$ 3.8	$ 27.6
Corporate segment
Goodwill [Line Items]
Asset impairment charges			$ 2.9	$ 2.7	$ 4.7