Pension And Postretirement Benefits (Details 2) (USD $) In Millions	12 Months Ended
May 29, 2011	May 30, 2010	May 31, 2009
Pension Benefits [Member]
Changes in benefit obligations and plan assets
Service cost	$ 59.7	$ 49.8	$ 50.7
Interest cost	147.5	148.1	141.2
Expected return on plan assets	(173.0)	(161.2)	(158.7)
Amortization of prior service cost (benefit)	3.2	3.2	3.0
Settlement loss		1.9
Special termination benefits	1.3
Recognized net actuarial (gain) loss	16.4	3.9	2.1
Curtailment loss		0.9
Benefit cost - Company plans	55.1	46.6	38.3
Pension benefit cost - multi-employer plans	9.2	9.7	8.6
Benefit Cost	64.3	56.3	46.9
Other Benefits [Member]
Changes in benefit obligations and plan assets
Service cost	0.6	0.5	0.8
Interest cost	16.3	18.3	20.6
Expected return on plan assets	(0.1)	(0.3)	(0.2)
Amortization of prior service cost (benefit)	(9.6)	(9.4)	(11.2)
Recognized net actuarial (gain) loss	4.6	(0.1)	4.8
Benefit cost - Company plans	11.8	9.0	14.8
Benefit Cost	$ 11.8	$ 9.0	$ 14.8

Benefit Cost.

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The net increase or decrease of changes in the value of either the benefit obligation or the plan assets resulting from experience different from that assumed or from a change in an actuarial assumption, or the consequence of a decision to temporarily deviate from the substantive plan.

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The amount of the prior service cost or credit recognized in net periodic benefit cost relating to benefit changes attributable to plan participants' prior service pursuant to a plan amendment or a plan initiation.

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An amount calculated as a basis for determining the extent of delayed recognition of the effects of changes in the fair value of assets. The expected return on plan assets is determined based on the expected long-term rate of return on plan assets and the market-related value 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 total amount of net periodic benefit cost for defined benefit plans for the period. Periodic benefit costs include the following components: service cost, interest cost, expected return on plan assets, gain (loss), prior service cost or credit, transition asset or obligation, and gain (loss) due to settlements or curtailments.

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The amount of net gain (loss) recognized in net periodic benefit cost as a result of an event that significantly reduces the expected years of future service of present employees or eliminates for a significant number of employees the accrual of defined benefits for some or all of their future services.

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The amount of net gain (loss) recognized in net periodic benefit cost as a result of an irrevocable action that relieves the employer (or the plan) of primary responsibility for a benefit obligation and eliminates significant risks related to the obligation and the assets used to effect the settlement. Examples of transactions that constitute a settlement include (a) making lump-sum cash payments to plan participants in exchange for their rights to receive specified benefits and (b) purchasing nonparticipating annuity contracts to cover vested benefits.

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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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Amount of contributions made to multiemployer plans for each period for which a statement of income is presented. An employer may disclose total contributions to multiemployer plans without disaggregating the amounts attributable to pension plans and other postretirement benefit plans.

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