Retirement and Postemployment Benefits (Schedule of components of net pension, other postretirement, and postemployment (income) expense) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Aug. 24, 2014	Aug. 25, 2013
Defined Benefit Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 34.4	$ 33.2
Interest cost	62.5	59.8
Expected return on plan assets	(119.3)	(113.8)
Amortization of losses	35.4	37.5
Amortization of prior service costs (credits)	1.9	1.4
Other adjustments	0	0
Net expense	14.9	18.1
Other Postretirement Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	5.6	5.9
Interest cost	11.8	12.6
Expected return on plan assets	(10.0)	(8.7)
Amortization of losses	1.2	3.8
Amortization of prior service costs (credits)	(0.4)	(0.9)
Other adjustments	0	0
Net expense	8.2	12.7
Postemployment Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	1.9	1.9
Interest cost	1.1	1.0
Expected return on plan assets	0	0
Amortization of losses	0.2	0.2
Amortization of prior service costs (credits)	0.6	0.6
Other adjustments	3.1	2.5
Net expense	$ 6.9	$ 6.2