Pension and Postretirement Benefits (Details) (USD $) In Millions	12 Months Ended
May 29, 2011	May 30, 2010	May 31, 2009
Change in Plan Assets
Fair value of plan assets at beginning of year	$ 2,144.6
Investment and administrative expenses	1,511.1	1,819.4	1,683.2
Fair value of plan assets at end of year	2,543.9	2,144.6
Pension Benefits [Member]
Change in Benefit Obligation
Benefit obligation at beginning of year	2,614.1	2,220.4
Service cost	59.7	49.8	50.7
Interest cost	147.5	148.1	141.2
Amendments	1.5	3.0
Actuarial loss	190.9	331.1
Special termination benefits	1.3
Benefits paid	(133.6)	(138.3)
Benefit obligation at end of year	2,881.4	2,614.1	2,220.4
Change in Plan Assets
Fair value of plan assets at beginning of year	2,144.6	1,903.2
Actual return on plan assets	418.3	268.3
Employer contributions	129.4	122.6
Investment and administrative expenses	(14.8)	(11.2)
Benefits paid	(133.6)	(138.3)
Fair value of plan assets at end of year	2,543.9	2,144.6	1,903.2
Other Benefits [Member]
Change in Benefit Obligation
Benefit obligation at beginning of year	324.9	288.6
Service cost	0.6	0.5	0.8
Interest cost	16.3	18.3	20.6
Plan participants' contributions	6.9	7.6
Amendments	(9.0)	6.2
Actuarial loss	19.4	42.0
Benefits paid	(36.5)	(38.3)
Benefit obligation at end of year	322.6	324.9	288.6
Change in Plan Assets
Fair value of plan assets at beginning of year	4.0	8.1
Employer contributions	25.7	26.6
Plan participants' contributions	6.9	7.6
Benefits paid	(36.5)	(38.3)
Fair value of plan assets at end of year	$ 0.1	$ 4.0	$ 8.1

Defined Benefit Plan Actuarial Gains Losses net.

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The difference between fair value of plan assets at the end of the period and the fair value at the beginning of the period, adjusted for contributions and payments of benefits during the period, and after adjusting for taxes and other expenses, as applicable.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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1) For defined benefit pension plans, the benefit obligation is the projected benefit obligation, which is the actuarial present value as of a date of all benefits attributed by the pension benefit formula to employee service rendered prior to that date. 2) For other postretirement defined benefit plans, the benefit obligation is the accumulated postretirement benefit obligation, which is the actuarial present value of benefits attributed to employee service rendered to a particular date.

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The amount of payments made for which participants are entitled under a pension plan, including pension benefits, death benefits, and benefits due on termination of employment. Also includes payments made under a postretirement benefit plan, including prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services. This item represents a periodic decrease to the plan obligations and a decrease to plan assets.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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The increase in the fair value of plan assets from contributions made by the employer.

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The amount of contributions made by plan participants. This item represents a periodic increase to the plan obligation and an increase to plan assets.

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Assets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those non-benefit obligations may be considered as reductions of plan assets.

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The increase in a defined benefit pension plan's projected benefit obligation or a defined benefit postretirement plan's accumulated postretirement benefit obligation due to the passage of time.

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The amount of increase or decrease due to a change in the terms of an existing plan or the initiation of a new plan. A plan amendment may increase or decrease benefits, including those attributed to years of service already rendered.

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The actuarial present value of benefits attributed by the pension benefit formula to services rendered by employees during the period. The portion of the expected postretirement benefit obligation attributed to employee service during the period. The service cost component is a portion of the benefit obligation and is unaffected by the funded status of the plan.

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The amount of increase related to special termination benefits offered to and accepted by employees in connection with their termination of employment that are only offered for a short period of time. A situation involving termination benefits may also involve a curtailment.

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The aggregate total costs related to selling a firm's product and services, as well as all other general and administrative expenses. Direct selling expenses (for example, credit, warranty, and advertising) are expenses that can be directly linked to the sale of specific products. Indirect selling expenses are expenses that cannot be directly linked to the sale of specific products, for example telephone expenses, Internet, and postal charges. General and administrative expenses include salaries of non-sales personnel, rent, utilities, communication, etc.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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