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Marketable Debt Securities - Available-for-Sale Marketable Securities (Detail) - USD ($) $ in Thousands | Nov. 23, 2019 | Aug. 31, 2019
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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

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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 + 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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