Marketable Debt Securities - Available-for-Sale Marketable Securities (Detail) - USD ($) $ in Thousands	May 09, 2020	May 04, 2019
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

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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