Retirement Benefits and Postemployment Benefits (Schedule of amounts expected to be recognized in net periodic expense next year) (Details) $ in Millions	May 27, 2018 USD ($)
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	$ 109.8
Amortization of prior service costs (credits)	1.5
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	0.6
Amortization of prior service costs (credits)	(5.5)
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	0.1
Amortization of prior service costs (credits)	$ 1.0