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INVESTMENTS IN JOINT VENTURES - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	May 26, 2019	May 27, 2018	May 28, 2017
Schedule of Equity Method Investments [Line Items]
Dividends received from equity method investments	$ 55.0	$ 62.5	$ 68.2
Other assets
Schedule of Equity Method Investments [Line Items]
Carrying value of equity method investments	796.3	776.2
Equity method investments
Schedule of Equity Method Investments [Line Items]
Purchases from equity method investees	$ 39.4
Sales to equity method investees		$ 34.9	$ 41.8
Ardent Mills
Schedule of Equity Method Investments [Line Items]
Ownership interest (as a percent)	44.00%
Others
Schedule of Equity Method Investments [Line Items]
Ownership interest (as a percent)	50.00%