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Marketable Debt Securities - Available-for-Sale Marketable Securities (Detail) - USD ($) $ in Thousands | May 09, 2020 | May 04, 2019
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Schedule of Available-for-sale Securities [Line Items] |  |
Available-For-Sale Marketable Securities, Amortized Cost Basis | $ 114,008 | $ 138,173
Available-For-Sale Marketable Securities, Gross Unrealized Gains | 2,311 | 794
Available-For-Sale Marketable Securities, Gross Unrealized Losses | (102) | (41)
Available-For-Sale Marketable Securities, Fair Value | 116,217 | 138,926
Corporate debt securities |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Available-For-Sale Marketable Securities, Amortized Cost Basis | 52,423 | 36,998
Available-For-Sale Marketable Securities, Gross Unrealized Gains | 715 | 29
Available-For-Sale Marketable Securities, Gross Unrealized Losses | (28) | (19)
Available-For-Sale Marketable Securities, Fair Value | 53,110 | 37,008
Government bonds |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Available-For-Sale Marketable Securities, Amortized Cost Basis | 45,683 | 45,741
Available-For-Sale Marketable Securities, Gross Unrealized Gains | 1,468 | 763
Available-For-Sale Marketable Securities, Gross Unrealized Losses | (13) |
Available-For-Sale Marketable Securities, Fair Value | 47,138 | 46,504
Mortgage-backed securities |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Available-For-Sale Marketable Securities, Amortized Cost Basis | 2,958 | 2,089
Available-For-Sale Marketable Securities, Gross Unrealized Gains | 58 | 2
Available-For-Sale Marketable Securities, Gross Unrealized Losses |  | (15)
Available-For-Sale Marketable Securities, Fair Value | 3,016 | 2,076
Asset-backed securities and other |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Available-For-Sale Marketable Securities, Amortized Cost Basis | 12,944 | 53,345
Available-For-Sale Marketable Securities, Gross Unrealized Gains | 70 |
Available-For-Sale Marketable Securities, Gross Unrealized Losses | (61) | (7)
Available-For-Sale Marketable Securities, Fair Value | $ 12,953 | $ 53,338

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- Definition 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). + 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 investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (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 (c) -URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27161-111563 + Details
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- Definition Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27161-111563 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=118942338&loc=SL82898722-210454 + Details
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