Marketable Securities - Available-for-Sale Marketable Securities (Detail) - USD ($) $ in Thousands	Aug. 25, 2018	Aug. 26, 2017
Schedule of Available-for-sale Securities [Line Items]
Available-For-Sale Marketable Securities, Amortized Cost Basis	$ 135,776	$ 100,885
Available-For-Sale Marketable Securities, Gross Unrealized Gains		152
Available-For-Sale Marketable Securities, Gross Unrealized Losses	(1,100)	(164)
Available-For-Sale Marketable Securities, Fair Value	134,676	100,873
Corporate Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-For-Sale Marketable Securities, Amortized Cost Basis	50,306	39,917
Available-For-Sale Marketable Securities, Gross Unrealized Gains		73
Available-For-Sale Marketable Securities, Gross Unrealized Losses	(684)	(13)
Available-For-Sale Marketable Securities, Fair Value	49,622	39,977
Government Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-For-Sale Marketable Securities, Amortized Cost Basis	28,777	31,076
Available-For-Sale Marketable Securities, Gross Unrealized Gains		49
Available-For-Sale Marketable Securities, Gross Unrealized Losses	(173)	(74)
Available-For-Sale Marketable Securities, Fair Value	28,604	31,051
Mortgage-Backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-For-Sale Marketable Securities, Amortized Cost Basis	3,248	4,850
Available-For-Sale Marketable Securities, Gross Unrealized Gains		2
Available-For-Sale Marketable Securities, Gross Unrealized Losses	(90)	(42)
Available-For-Sale Marketable Securities, Fair Value	3,158	4,810
Asset-Backed Securities and Other [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-For-Sale Marketable Securities, Amortized Cost Basis	53,445	25,042
Available-For-Sale Marketable Securities, Gross Unrealized Gains		28
Available-For-Sale Marketable Securities, Gross Unrealized Losses	(153)	(35)
Available-For-Sale Marketable Securities, Fair Value	$ 53,292	$ 25,035

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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