Marketable Securities - Additional Information (Detail) $ in Thousands	12 Months Ended
Aug. 25, 2018 USD ($) Securities	Aug. 26, 2017 USD ($)
Investments, Debt and Equity Securities [Abstract]
Available for sale securities debt maturity period range	Less than one year to approximately three years
Number of securities available for sale loss position \| Securities	121
Available-For-Sale Marketable Securities, Gross Unrealized Losses	$ 1,100	$ 164
Marketable securities transferred	$ 85,600	$ 85,400

The time period allotted for available-for-sale securities to mature.

No definition available.

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- Definition

The total amount of cash and securities held by third party trustees pursuant to terms of debt instruments or other agreements as of the date of each statement of financial position presented, which can be used by the trustee only to pay the noncurrent portion of specified obligations.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(b))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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- Definition

Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

No definition available.

+ Details

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- Definition

Number of investment positions in available-for-sale investments in a continuous unrealized loss position for which an other-than-temporary impairment (OTTI) has not been recognized in the income statement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 6
-Subparagraph (b)(3)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27290-111563

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- References

No definition available.

+ Details

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