Retirement Benefits and Postemployment Benefits (Schedule of amounts expected to be recognized in net periodic expense next year) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	May 26, 2013
Defined Benefit Pension Plans [Member]
Defined Benefit Plan Amounts That Will Be Amortized From Accumulated Other Comprehensive Income Loss In Next Fiscal Year [Abstract]
Amortization of losses	$ 151.1
Amortization of prior service costs (credits)	5.6
Other Postretirement Benefit Plans [Member]
Defined Benefit Plan Amounts That Will Be Amortized From Accumulated Other Comprehensive Income Loss In Next Fiscal Year [Abstract]
Amortization of losses	15.4
Amortization of prior service costs (credits)	(3.4)
Postemployment Benefit Plans [Member]
Defined Benefit Plan Amounts That Will Be Amortized From Accumulated Other Comprehensive Income Loss In Next Fiscal Year [Abstract]
Amortization of losses	0.6
Amortization of prior service costs (credits)	$ 2.4