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Amortized Cost and Fair Value of Available-for-Sale Investments (Detail) - USD ($) $ in Thousands | Sep. 27, 2025 | Dec. 28, 2024
--- | --- | ---
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | $ 146,288 | $ 147,438
Gross Unrealized Gains | 1,057 | 223
Gross Unrealized Losses | 1,979 | 3,796
Fair Value | 145,366 | 143,865
Money market investments |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 5,998 | 13,473
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | 0 | 0
Fair Value | 5,998 | 13,473
Asset-backed securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 21,686 | 26,785
Gross Unrealized Gains | 57 | 25
Gross Unrealized Losses | 1,240 | 1,770
Fair Value | 20,503 | 25,040
Corporate bonds, commercial paper and direct obligations of government agencies |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 103,735 | 107,180
Gross Unrealized Gains | 993 | 198
Gross Unrealized Losses | 739 | 2,026
Fair Value | 103,989 | $ 105,352
U.S. Treasury obligations |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 14,869 |
Gross Unrealized Gains | 7 |
Gross Unrealized Losses | 0 |
Fair Value | $ 14,876 |

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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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