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Marketable Securities - Available-for-Sale Marketable Securities (Detail) - USD ($) $ in Thousands | Aug. 25, 2018 | Aug. 26, 2017
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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

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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 + Details
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- Definition 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. + Details
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- Definition This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any. + References No definition available. + Details
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