Accumulated Other Comprehensive Loss - Changes in Accumulated Other Comprehensive Loss (Parenthetical) (Detail) - USD ($) $ in Thousands	3 Months Ended
Nov. 19, 2016	Nov. 21, 2015
Accumulated Other Comprehensive Income (Loss) [Line Items]
Pension liability adjustments, taxes	$ 1,385	$ 1,190
Unrealized Gains (losses) on marketable securities, taxes	144	33
Net derivative activities, taxes	179	85
Reclassified from Accumulated Other Comprehensive Income [Member] \| Pension Liability [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Pension liability adjustments, taxes	1,385	1,190
Reclassified from Accumulated Other Comprehensive Income [Member] \| Net Unrealized Gain (Loss) on Securities [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Unrealized Gains (losses) on marketable securities, taxes	3	7
Reclassified from Accumulated Other Comprehensive Income [Member] \| Derivatives [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Net derivative activities, taxes	$ 179	$ 85

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of tax (expense) benefit, after reclassification adjustments, of (increase) decrease in accumulated other comprehensive (income) loss related to pension and other postretirement defined benefit plans.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=66004124&loc=d3e640-108580

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 10A
-Subparagraph (i-k)
-URI http://asc.fasb.org/extlink&oid=66004124&loc=SL7669646-108580

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Amount of tax expense (benefit), before reclassification adjustments, related to increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=66004124&loc=d3e640-108580

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 10A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=66004124&loc=SL7669646-108580

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Amount of tax expense (benefit) before reclassification adjustments of unrealized holding gain (loss) on available-for-sale securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=66004124&loc=d3e640-108580

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-Topic 220
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-Section 45
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-URI http://asc.fasb.org/extlink&oid=66004124&loc=SL7669646-108580

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