PENSION AND POSTRETIREMENT BENEFITS (Components) (Details) - USD ($) $ in Millions	12 Months Ended
	May. 31, 2015	May. 25, 2014	May. 26, 2013
Pension Benefits
Changes in benefit obligations and plan assets
Service cost	$ 88.5	$ 89.0	$ 81.8
Interest cost	161.3	151.1	150.1
Expected return on plan assets	(267.9)	(252.9)	(216.4)
Amortization of prior service cost (benefit)	3.7	3.8	3.6
Special termination benefits	6.9	0.4	0.0
Recognized net actuarial loss	6.9	2.7	3.6
Curtailment loss	1.5	0.0	0.8
Benefit cost — Company plans	0.9	(5.9)	23.5
Pension benefit cost — multi-employer plans	12.4	12.6	23.6
Total benefit cost	13.3	6.7	47.1
Other Benefits
Changes in benefit obligations and plan assets
Service cost	0.6	0.7	0.6
Interest cost	9.9	9.7	10.5
Expected return on plan assets	0.0	0.0	0.0
Amortization of prior service cost (benefit)	(7.9)	(7.2)	(8.2)
Special termination benefits	0.0	0.0	0.0
Recognized net actuarial loss	3.5	6.7	5.9
Curtailment loss	0.0	0.0	0.0
Benefit cost — Company plans	6.1	9.9	8.8
Pension benefit cost — multi-employer plans	0.0	0.0	0.0
Total benefit cost	$ 6.1	$ 9.9	$ 8.8