Pension and Savings Plans - Additional Information (Detail) - USD ($)	12 Months Ended
Aug. 27, 2016	Aug. 29, 2015	Aug. 30, 2014
Compensation and Retirement Disclosure [Abstract]
Consecutive years of highest compensation used to determine defined benefit pension plan benefits	5 years
Cash contribution in asset allocation	$ 48,000,000	$ 11,500,000
Expected long-term rate of return on plan assets	7.00%	7.00%	7.50%
Plan benefit service cost	$ 0
Change to net periodic benefit cost	1,800,000
Annual contributions by the Company to pension plans	52,721,000	$ 17,077,000	$ 16,900,000
Expected contributions to the plans by the Company in next 12 months	$ 17,800,000
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	$ 19,700,000	$ 17,700,000	$ 15,600,000

Number of consecutive years of highest compensation used to determine defined benefit pension plan benefits.

No definition available.

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- Definition

The cash contribution to the defined benefit plan that will not be fully allocated to the pension plan investments in accordance with the targeted asset allocation until after the end of the fiscal year.

+ References

No definition available.

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- Definition

Defined benefit plan net periodic benefit costs period increase decrease.

+ References

No definition available.

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- Definition

Maximum percentage of qualified earnings that can be contributed to the savings plan.

+ References

No definition available.

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- 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
-Glossary Expected Long-Term Rate of Return on Plan Assets
-URI http://asc.fasb.org/extlink&oid=6512046

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=65897934&loc=d3e1928-114920

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- Definition

Amount of contributions made by the employer to defined benefit plans.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (d)(5)(ii)
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-Publisher FASB
-Name Accounting Standards Codification
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-Section 35
-Paragraph 123
-Subparagraph B
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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
-Glossary Service Cost (Component of Net Periodic Pension Cost)
-URI http://asc.fasb.org/extlink&oid=6525008

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
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- Definition

Amount of employer's best estimate of contributions expected to be paid to the plan during the next fiscal year beginning after the date of the latest statement of financial position.

+ References

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- Definition

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

+ References

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=66902209&loc=d3e3536-108585

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