Marketable Debt Securities - Available-for-Sale Marketable Securities (Detail) - USD ($) $ in Thousands	Aug. 29, 2020	Aug. 31, 2019
Schedule of Available-for-sale Securities [Line Items]
Available-For-Sale Marketable Securities, Amortized Cost Basis	$ 144,886	$ 138,173
Available-For-Sale Marketable Securities, Gross Unrealized Gains	2,360	794
Available-For-Sale Marketable Securities, Gross Unrealized Losses	(7)	(41)
Available-For-Sale Marketable Securities, Fair Value	147,239	138,926
Corporate Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-For-Sale Marketable Securities, Amortized Cost Basis	46,652	36,998
Available-For-Sale Marketable Securities, Gross Unrealized Gains	970	29
Available-For-Sale Marketable Securities, Gross Unrealized Losses	(4)	(19)
Available-For-Sale Marketable Securities, Fair Value	47,618	37,008
Government Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-For-Sale Marketable Securities, Amortized Cost Basis	44,594	45,741
Available-For-Sale Marketable Securities, Gross Unrealized Gains	1,172	763
Available-For-Sale Marketable Securities, Fair Value	45,766	46,504
Mortgage-Backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-For-Sale Marketable Securities, Amortized Cost Basis	4,842	2,089
Available-For-Sale Marketable Securities, Gross Unrealized Gains	75	2
Available-For-Sale Marketable Securities, Gross Unrealized Losses		(15)
Available-For-Sale Marketable Securities, Fair Value	4,917	2,076
Asset-Backed Securities and Other [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-For-Sale Marketable Securities, Amortized Cost Basis	48,798	53,345
Available-For-Sale Marketable Securities, Gross Unrealized Gains	143
Available-For-Sale Marketable Securities, Gross Unrealized Losses	(3)	(7)
Available-For-Sale Marketable Securities, Fair Value	$ 48,938	$ 53,338

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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