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Marketable Securities - Additional Information (Detail) $ in Thousands	5 Months Ended
	Feb. 10, 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	112
Available-For-Sale Marketable Securities, Gross Unrealized Losses	$ 893	$ 164
Marketable securities transferred	$ 85,000

X

- Definition

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

+ References

No definition available.

+ Details

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X

- Definition

Amount transferred by the Company's insurance captive to a Trust Account for future obligations.

+ References

No definition available.

+ Details

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X

- 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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27161-111563

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X

- 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://www.xbrl.org/2003/role/presentationRef
-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

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