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Schedule of Unrealized Loss on Available-for-Sale Investments (Detail) - USD ($) $ in Thousands | Sep. 27, 2025 | Dec. 28, 2024
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Debt Securities, Available-for-sale [Line Items] |  |
Available-for-sale investments with unrealized losses, Less than 12 months, Fair Value | $ 20,836 | $ 28,072
Available-for-sale investments with unrealized losses, Less than 12 months, Unrealized Loss | 541 | 206
Available-for-sale investments with unrealized losses, 12 months or longer, Fair Value | 26,403 | 72,205
Available-for-sale investments with unrealized losses, 12 months or longer, Unrealized Loss | 1,438 | 3,590
Available-for-sale investments with unrealized losses, Fair Value, Total | 47,239 | 100,277
Available-for-sale investments with unrealized losses, Unrealized Loss, Total | 1,979 | 3,796
Asset-backed securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Available-for-sale investments with unrealized losses, Less than 12 months, Fair Value | 4,537 | 9,663
Available-for-sale investments with unrealized losses, Less than 12 months, Unrealized Loss | 411 | 37
Available-for-sale investments with unrealized losses, 12 months or longer, Fair Value | 9,400 | 12,596
Available-for-sale investments with unrealized losses, 12 months or longer, Unrealized Loss | 829 | 1,733
Available-for-sale investments with unrealized losses, Fair Value, Total | 13,937 | 22,259
Available-for-sale investments with unrealized losses, Unrealized Loss, Total | 1,240 | 1,770
Corporate bonds, commercial paper, and direct obligations of government agencies |  |
Debt Securities, Available-for-sale [Line Items] |  |
Available-for-sale investments with unrealized losses, Less than 12 months, Fair Value | 16,299 | 18,409
Available-for-sale investments with unrealized losses, Less than 12 months, Unrealized Loss | 130 | 169
Available-for-sale investments with unrealized losses, 12 months or longer, Fair Value | 17,003 | 59,609
Available-for-sale investments with unrealized losses, 12 months or longer, Unrealized Loss | 609 | 1,857
Available-for-sale investments with unrealized losses, Fair Value, Total | 33,302 | 78,018
Available-for-sale investments with unrealized losses, Unrealized Loss, Total | $ 739 | $ 2,026

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