Retirement Benefits and Postemployment Benefits (Schedule of summarized financial information about defined benefit pension, other postretirement, and postemployment benefit plans) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	May 26, 2013	May 27, 2012	May 29, 2011
Defined Benefit Pension Plans [Member]
Defined Benefit Plan Change In Fair Value Of Plan Assets Roll Forward [Abstract]
Fair value at beginning of year	$ 4,353.9	$ 4,264.0
Actual return on assets	698.7	56.3
Employer contributions	223.1	222.1
Plan participant contributions	15.2	20.3
Benefits Payments	(222.6)	(203.3)
Foreign currency	(2.2)	(5.5)
Fair value at end of year	5,066.1	4,353.9	4,264.0
Defined Benefit Plan Change In Benefit Obligation Roll Forward [Abstract]
Benefit obligation at beginning of year	4,991.5	4,458.4
Service cost	124.4	114.3	101.4
Interest cost	237.3	237.9	230.9
Plan amendment	0.2	(13.4)
Curtailment/other	0	(27.1)
Plan participant contributions	15.2	20.3
Medicare Part D reimbursements	0	0
Actuarial loss (gain)	237.5	405.7
Benefits payments	(222.8)	(203.5)
Foreign currency	(1.9)	(5.9)
Acquisitions	0	4.8
Projected benefit obligation at end of year	5,381.4	4,991.5	4,458.4
Plan assets less than benefit obligation as of fiscal year end	(315.3)	(637.6)
Other Postretirement Benefit Plans [Member]
Defined Benefit Plan Change In Fair Value Of Plan Assets Roll Forward [Abstract]
Fair value at beginning of year	358.8	353.8
Actual return on assets	67.9	(4.8)
Employer contributions	0.1	0.1
Plan participant contributions	13.0	12.2
Benefits Payments	(2.9)	(2.5)
Foreign currency	0	0
Fair value at end of year	436.9	358.8	353.8
Defined Benefit Plan Change In Benefit Obligation Roll Forward [Abstract]
Benefit obligation at beginning of year	1,129.0	1,065.8
Service cost	21.6	18.0	18.7
Interest cost	52.1	55.6	60.1
Plan amendment	0	0
Curtailment/other	0	0.1
Plan participant contributions	13.0	12.2
Medicare Part D reimbursements	4.1	4.7
Actuarial loss (gain)	(23.0)	28.4
Benefits payments	(58.9)	(55.5)
Foreign currency	(0.1)	(0.3)
Acquisitions	10.4	0
Projected benefit obligation at end of year	1,148.2	1,129.0	1,065.8
Plan assets less than benefit obligation as of fiscal year end	(711.3)	(770.2)
Postemployment Benefit Plans [Member]
Defined Benefit Plan Change In Fair Value Of Plan Assets Roll Forward [Abstract]
Plan participant contributions	0	0
Defined Benefit Plan Change In Benefit Obligation Roll Forward [Abstract]
Benefit obligation at beginning of year	141.3	131.3
Service cost	7.8	7.5	8.0
Interest cost	4.4	4.8	5.1
Plan amendment	4.5	0
Curtailment/other	11.4	11.9
Plan participant contributions	0	0
Medicare Part D reimbursements	0	0
Actuarial loss (gain)	(10.4)	5.5
Benefits payments	(13.6)	(19.6)
Foreign currency	0	(0.1)
Acquisitions	0	0
Projected benefit obligation at end of year	145.4	141.3	131.3
Plan assets less than benefit obligation as of fiscal year end	$ (145.4)	$ (141.3)