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Amortized Cost and Fair Value of Available-for-Sale Investments (Detail) - USD ($) $ in Thousands | Sep. 28, 2024 | Dec. 30, 2023
--- | --- | ---
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | $ 151,390 | $ 158,143
Gross Unrealized Gains | 1,019 | 281
Gross Unrealized Losses | 3,550 | 6,663
Fair Value | 148,859 | 151,761
Money market investments |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 14,998 | 16,832
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | 0 | 0
Fair Value | 14,998 | 16,832
Asset-backed securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 17,535 | 16,543
Gross Unrealized Gains | 21 | 0
Gross Unrealized Losses | 1,563 | 2,236
Fair Value | 15,993 | 14,307
Corporate bonds, commercial paper and direct obligations of government agencies |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 118,857 | 118,481
Gross Unrealized Gains | 998 | 279
Gross Unrealized Losses | 1,987 | 4,384
Fair Value | $ 117,868 | 114,376
U.S. Treasury obligations |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost |  | 6,287
Gross Unrealized Gains |  | 2
Gross Unrealized Losses |  | 43
Fair Value |  | $ 6,246

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