Pension and Savings Plans - Additional Information (Detail) (USD $)	12 Months Ended
Aug. 25, 2012	Aug. 27, 2011	Aug. 28, 2010
Number of consecutive years of highest compensation used to determine defined benefit pension plan benefits	5 years
Pension plan asset constituted in alternate investment strategies	Less than 2%
Hedge fund managers diversified over hedge strategies	16
Different hedge strategies	9
Cash contribution in asset allocation	$ 8,700,000	$ 28,300,000
Expected long-term rate of return on plan assets	7.50%	8.00%	8.00%
Annual contributions by the company to pension plans	15,423,000	34,076,000	12,000
Expected contributions to the plan in fiscal 2013	9,000,000
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	$ 14,400,000	$ 13,300,000	$ 11,700,000

Asset constituted in alternate investment strategies.

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- Definition

Defined benefit plan cash contributed during period still held.

+ References

No definition available.

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- Definition

Different hedge strategies.

+ References

No definition available.

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- Definition

Estimated Future Employer Contributions in the Current Fiscal Year.

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- Definition

Hedge fund managers diversified over hedge strategies.

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- Definition

Number Of Consecutive Years Of Highest Compensation Used To Determine Defined Benefit Pension Plan Benefits.

+ References

No definition available.

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- Definition

Percentage of company matching retirement savings plan contributions that vest immediately.

+ References

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 20

-Section 50

-Paragraph 1

-Subparagraph (k)(3)

-URI http://asc.fasb.org/extlink&oid=21915506&loc=d3e1928-114920

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 87

-Paragraph 264

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 132R

-Paragraph 5

-Subparagraph j

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: 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

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- Definition

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

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 132R

-Paragraph 5

-Subparagraph b

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

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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 Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 28

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 25

-Subparagraph (g)

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