PENSION AND POSTRETIREMENT BENEFITS - Schedule of Contributions for Plans That Are Not Individually Significant (Details) - USD ($) $ in Millions	12 Months Ended
	May 26, 2019	May 27, 2018	May 28, 2017
Multiemployer Plans [Line Items]
Total Contributions	$ 6.0	$ 6.5	$ 8.0
Bakery and Confectionary Union and Industry International Pension Plan
Multiemployer Plans [Line Items]
Total Contributions	0.1	1.5	1.8
Central States, Southeast and Southwest Areas Pension Fund
Multiemployer Plans [Line Items]
Total Contributions	1.8	1.8	1.8
Western Conference of Teamsters Pension Plan
Multiemployer Plans [Line Items]
Total Contributions	3.2	2.8	4.0
Other Plans
Multiemployer Plans [Line Items]
Total Contributions	$ 0.9	$ 0.4	$ 0.4