Marketable Debt Securities - Available-for-Sale Marketable Securities (Detail) - USD ($) $ in Thousands	Nov. 23, 2019	Aug. 31, 2019
Schedule of Available-for-sale Securities [Line Items]
Available-For-Sale Marketable Securities, Amortized Cost Basis	$ 127,857	$ 138,173
Available-For-Sale Marketable Securities, Gross Unrealized Gains	554	794
Available-For-Sale Marketable Securities, Gross Unrealized Losses	(40)	(41)
Available-For-Sale Marketable Securities, Fair Value	128,371	138,926
Corporate Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-For-Sale Marketable Securities, Amortized Cost Basis	35,093	36,998
Available-For-Sale Marketable Securities, Gross Unrealized Gains	34	29
Available-For-Sale Marketable Securities, Gross Unrealized Losses	(6)	(19)
Available-For-Sale Marketable Securities, Fair Value	35,121	37,008
Government Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-For-Sale Marketable Securities, Amortized Cost Basis	60,901	45,741
Available-For-Sale Marketable Securities, Gross Unrealized Gains	515	763
Available-For-Sale Marketable Securities, Gross Unrealized Losses	(18)	0
Available-For-Sale Marketable Securities, Fair Value	61,398	46,504
Mortgage-Backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-For-Sale Marketable Securities, Amortized Cost Basis	1,787	2,089
Available-For-Sale Marketable Securities, Gross Unrealized Gains	1	2
Available-For-Sale Marketable Securities, Gross Unrealized Losses	(14)	(15)
Available-For-Sale Marketable Securities, Fair Value	1,774	2,076
Asset-Backed Securities and Other [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-For-Sale Marketable Securities, Amortized Cost Basis	30,076	53,345
Available-For-Sale Marketable Securities, Gross Unrealized Gains	4	0
Available-For-Sale Marketable Securities, Gross Unrealized Losses	(2)	(7)
Available-For-Sale Marketable Securities, Fair Value	$ 30,078	$ 53,338

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=118939692&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

No definition available.

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+ References

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+ References

No definition available.

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