Employee and Retiree Benefits (Postretirement Benefit Income) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	9 Months Ended
May 31, 2014	Jun. 01, 2013	May 31, 2014	Jun. 01, 2013
Compensation and Retirement Disclosure [Abstract]
Interest cost	$ 380	$ 373	$ 1,160	$ 1,136
Service cost	96	140	296	433
Amortization of prior service benfit	(1,482)	(1,366)	(4,168)	(3,803)
Amortization of net actuarial loss	274	407	803	1,195
Net periodic postretirement benefit income	(732)	(446)	(1,909)	(1,039)
Payments for postretirement health care	$ 247	$ 271	$ 779	$ 836

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The amount of gains or losses recognized in net periodic benefit cost.

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- Definition

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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- Definition

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.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Postretirement Benefits

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-Publisher FASB

-Name Accounting Standards Codification

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-Glossary Benefits

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- Definition

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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- Definition

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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- Definition

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.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

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-Paragraph 1

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