Pension and Savings Plans - Additional Information (Detail) (USD $)	12 Months Ended
Aug. 31, 2013 Hedge_Fund_Manager Hedge_Strategies	Aug. 25, 2012	Aug. 27, 2011
Compensation And Retirement Disclosure [Abstract]
Consecutive years of highest compensation used to determine defined benefit pension plan benefits	5 years
Pension plan asset constituted in alternate investment strategies	1.00%
Hedge fund managers diversified over hedge strategies	9
Different hedge strategies	4
Cash contribution in asset allocation	$ 11,000,000	$ 8,700,000
Expected long-term rate of return on plan assets	7.50%	7.50%	8.00%
Plan benefit service cost	0
Annual contributions by the Company to pension plans	16,909,000	15,423,000	34,100,000
Expected contributions to the plans by the Company in fiscal 2014	4,000,000
Percentage of company matching retirement savings plan contributions that vest immediately	100.00%
Percentage of savings option up to qualified earnings	25.00%
Annual contribution by employer towards 401(k) Plan	$ 14,100,000	$ 14,400,000	$ 13,300,000

Defined benefit plan assumptions consecutive period of highest average compensation.

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Defined benefit plan cash contributed during period still held.

+ References

No definition available.

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- Definition

Number of hedge fund managers.

+ References

No definition available.

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Number of hedge strategies.

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No definition available.

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- Definition

Savings option percentage maximum of qualified earnings.

+ References

No definition available.

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- Definition

An assumption as to the rate of return on plan assets reflecting the average rate of earnings expected on the funds invested or to be invested to provide for the benefits included in the benefit obligation.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 30

-Glossary Expected Long-Term Rate of Return on Plan Assets

-URI http://asc.fasb.org/extlink&oid=6512013

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (k)(3)

-URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920

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- Definition

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

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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

-Section 50

-Paragraph 1

-Subparagraph (h)(1)

-URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Service Cost (Component of Net Periodic Pension Cost)

-URI http://asc.fasb.org/extlink&oid=6525008

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920

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- Definition

Amount of employer's best estimate of contributions expected to be paid to the plan in the current remaining fiscal period.

+ References

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- Definition

Target allocation maximum percentage of investments of this type to total plan assets presented on a weighted average basis.

+ References

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- Definition

Percentage of employer's matching contributions to a defined contribution plan that vests in a given year.

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No definition available.

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- Definition

The amount of cash or cash equivalents contributed during the reporting period by the entity to fund non-pension postretirement benefits.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 25

-Subparagraph (g)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3536-108585

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