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FAIR VALUE MEASUREMENTS - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Feb. 28, 2021	Aug. 30, 2020	Feb. 27, 2022	Feb. 28, 2021	May 30, 2021
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Asset impairment charges			$ 72.7	$ 4.2
Increase in long-lived assets	$ 27.4
Carrying amount of long-term debt (including current installments)			8,800.0		$ 8,300.0
Estimated fair value of debt			9,540.0		$ 9,760.0
Minimum
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Long-lived assets additional depreciation in future periods	15 years
Maximum
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Long-lived assets additional depreciation in future periods	25 years
Grocery & Snacks
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Asset impairment charges		$ 3.0	26.3
Refrigerated & Frozen
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Asset impairment charges			28.9
Foodservice
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Asset impairment charges			$ 14.9