Marketable Debt Securities - Available-for-Sale Marketable Securities (Detail) - USD ($) $ in Thousands	Nov. 21, 2020	Aug. 29, 2020
Schedule of Available-for-sale Securities [Line Items]
Available-For-Sale Marketable Securities, Amortized Cost Basis	$ 139,661	$ 144,886
Available-For-Sale Marketable Securities, Gross Unrealized Gains	1,983	2,360
Available-For-Sale Marketable Securities, Gross Unrealized Losses	(21)	(7)
Available-For-Sale Marketable Securities, Fair Value	141,623	147,239
Corporate debt securities
Schedule of Available-for-sale Securities [Line Items]
Available-For-Sale Marketable Securities, Amortized Cost Basis	42,192	46,652
Available-For-Sale Marketable Securities, Gross Unrealized Gains	816	970
Available-For-Sale Marketable Securities, Gross Unrealized Losses		(4)
Available-For-Sale Marketable Securities, Fair Value	43,008	47,618
Government bonds
Schedule of Available-for-sale Securities [Line Items]
Available-For-Sale Marketable Securities, Amortized Cost Basis	75,235	44,594
Available-For-Sale Marketable Securities, Gross Unrealized Gains	968	1,172
Available-For-Sale Marketable Securities, Gross Unrealized Losses	(18)
Available-For-Sale Marketable Securities, Fair Value	76,185	45,766
Mortgage-backed securities
Schedule of Available-for-sale Securities [Line Items]
Available-For-Sale Marketable Securities, Amortized Cost Basis	6,590	4,842
Available-For-Sale Marketable Securities, Gross Unrealized Gains	68	75
Available-For-Sale Marketable Securities, Gross Unrealized Losses	(1)
Available-For-Sale Marketable Securities, Fair Value	6,657	4,917
Asset-backed securities and other
Schedule of Available-for-sale Securities [Line Items]
Available-For-Sale Marketable Securities, Amortized Cost Basis	15,644	48,798
Available-For-Sale Marketable Securities, Gross Unrealized Gains	131	143
Available-For-Sale Marketable Securities, Gross Unrealized Losses	(2)	(3)
Available-For-Sale Marketable Securities, Fair Value	$ 15,773	$ 48,938

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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