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Amortized Cost and Fair Value of Available-for-Sale Investments (Detail) - USD ($) $ in Thousands | Dec. 30, 2023 | Dec. 31, 2022
--- | --- | ---
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | $ 158,143 | $ 169,293
Gross Unrealized Gains | 281 | 1
Gross Unrealized Losses | 6,663 | 10,764
Fair Value | 151,761 | 158,530
Money market investments |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 16,832 | 21,910
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | 0 | 0
Fair Value | 16,832 | 21,910
Asset-backed securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 16,543 | 18,905
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | 2,236 | 2,889
Fair Value | 14,307 | 16,016
Corporate bonds and direct obligations of government agencies |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 118,481 | 126,134
Gross Unrealized Gains | 279 | 1
Gross Unrealized Losses | 4,384 | 7,775
Fair Value | 114,376 | 118,360
U.S. Treasury obligations |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 6,287 | 2,344
Gross Unrealized Gains | 2 | 0
Gross Unrealized Losses | 43 | 100
Fair Value | $ 6,246 | $ 2,244

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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://www.xbrl.org/2003/role/disclosureRef -Topic 320 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org//1943274/2147481800/320-10-50-2 + Details
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