PENSION AND POSTRETIREMENT BENEFITS (Costs) (Details) - USD ($) $ in Millions	3 Months Ended
	Aug. 30, 2015	Aug. 24, 2014
Pension Benefits
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service cost	$ 23.8	$ 22.1
Interest cost	41.0	40.4
Expected return on plan assets	(66.9)	(67.0)
Amortization of prior service cost	0.7	0.9
Special termination benefits	0.0	6.9
Benefit cost — Company plans	(1.4)	3.3
Pension benefit cost — multi-employer plans	2.3	3.2
Total benefit cost	0.9	6.5
Postretirement Benefits
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service cost	0.1	0.1
Interest cost	2.0	2.5
Amortization of prior service cost	(2.0)	(2.0)
Recognized net actuarial loss	0.0	0.9
Total benefit cost	$ 0.1	$ 1.5