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Pension and Savings Plans - Additional Information (Detail) - USD ($) | 12 Months Ended
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Aug. 25, 2018 | Aug. 26, 2017 | Aug. 27, 2016 | Aug. 29, 2015
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Consecutive years of highest compensation used to determine defined benefit pension plan benefits |  | 5 years |  |
Cash contribution in asset allocation |  | $ 17.5 | $ 48.0 |
Expected long-term rate of return on plan assets |  | 7.00% | 7.00% | 7.00%
Plan benefit service cost |  | $ 0 |  |
Change to net periodic benefit cost |  |  | $ 1,800,000 |
Annual contributions by the Company to pension plans |  | 17,761,000 | 52,721,000 | $ 17,100,000
Expected contributions to the plans by the Company in next 12 months |  | $ 20,300,000 |  |
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 |  | $ 21,000,000 | $ 19,700,000 | $ 17,700,000
Scenario Forecast [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Expected long-term rate of return on plan assets | 6.00% |  |  |

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- Definition Number of consecutive years of highest compensation used to determine defined benefit pension plan benefits. + References No definition available. + Details
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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. + Details
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- Definition Defined benefit plan net periodic benefit costs period increase decrease. + References No definition available. + Details
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- Definition Maximum percentage of qualified earnings that can be contributed to the savings plan. + References No definition available. + Details
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- Definition Weighted average rate of return on plan assets, reflecting average rate of earnings expected on existing plan assets and expected contributions, used to determine net periodic benefit cost of defined benefit 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 (k)(3) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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- Definition Amount of contribution received by defined benefit plan from employer which increases plan assets. + 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 (d)(5)(ii) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 6 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e2709-114920 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b)(3) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(5)(iv)(01) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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- Definition Amount of cost for actuarial present value of benefits attributed to service rendered by employee for defined benefit 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=82843861&loc=d3e1928-114920 Reference 2: 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=82843861&loc=d3e1928-114920 + Details
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- Definition Amount of payment for other postretirement benefits. Excludes pension 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=98514028&loc=d3e3536-108585 + Details
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