Marketable Debt Securities - Available-for-Sale Marketable Securities (Detail) - USD ($) $ in Thousands	Feb. 09, 2019	Aug. 25, 2018
Schedule of Available-for-sale Securities [Line Items]
Available-For-Sale Marketable Securities, Amortized Cost Basis	$ 122,299	$ 135,776
Available-For-Sale Marketable Securities, Gross Unrealized Gains	97
Available-For-Sale Marketable Securities, Gross Unrealized Losses	(652)	(1,100)
Available-For-Sale Marketable Securities, Fair Value	121,744	134,676
Corporate Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-For-Sale Marketable Securities, Amortized Cost Basis	42,817	50,306
Available-For-Sale Marketable Securities, Gross Unrealized Losses	(412)	(684)
Available-For-Sale Marketable Securities, Fair Value	42,405	49,622
Government Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-For-Sale Marketable Securities, Amortized Cost Basis	38,670	28,777
Available-For-Sale Marketable Securities, Gross Unrealized Gains	97
Available-For-Sale Marketable Securities, Gross Unrealized Losses	(95)	(173)
Available-For-Sale Marketable Securities, Fair Value	38,672	28,604
Mortgage-Backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-For-Sale Marketable Securities, Amortized Cost Basis	2,635	3,248
Available-For-Sale Marketable Securities, Gross Unrealized Losses	(60)	(90)
Available-For-Sale Marketable Securities, Fair Value	2,575	3,158
Asset-Backed Securities and Other [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-For-Sale Marketable Securities, Amortized Cost Basis	38,177	53,445
Available-For-Sale Marketable Securities, Gross Unrealized Losses	(85)	(153)
Available-For-Sale Marketable Securities, Fair Value	$ 38,092	$ 53,292

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27161-111563

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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

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+ References

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+ References

No definition available.

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