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Schedule of Unrealized Loss on Available-for-Sale Investments (Detail) - USD ($) $ in Thousands | Dec. 31, 2022 | Dec. 25, 2021
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Debt Securities, Available-for-sale [Line Items] |  |
Available-for-sale investments with unrealized losses, Less than 12 months, Fair Value | $ 56,275 | $ 94,621
Available-for-sale investments with unrealized losses, Less than 12 months, Unrealized Loss | 1,616 | 1,312
Available-for-sale investments with unrealized losses, 12 months or longer, Fair Value | 78,406 | 0
Available-for-sale investments with unrealized losses, 12 months or longer, Unrealized Loss | 9,148 | 0
Available-for-sale investments with unrealized losses, Fair Value, Total | 134,681 | 94,621
Available-for-sale investments with unrealized losses, Unrealized Loss, Total | 10,764 | 1,312
Asset-backed securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Available-for-sale investments with unrealized losses, Less than 12 months, Fair Value | 0 | 22,095
Available-for-sale investments with unrealized losses, Less than 12 months, Unrealized Loss | 0 | 346
Available-for-sale investments with unrealized losses, 12 months or longer, Fair Value | 16,016 | 0
Available-for-sale investments with unrealized losses, 12 months or longer, Unrealized Loss | 2,889 | 0
Available-for-sale investments with unrealized losses, Fair Value, Total | 16,016 | 22,095
Available-for-sale investments with unrealized losses, Unrealized Loss, Total | 2,889 | 346
Corporate bonds 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 | 54,031 | 72,526
Available-for-sale investments with unrealized losses, Less than 12 months, Unrealized Loss | 1,516 | 966
Available-for-sale investments with unrealized losses, 12 months or longer, Fair Value | 62,390 | 0
Available-for-sale investments with unrealized losses, 12 months or longer, Unrealized Loss | 6,259 | 0
Available-for-sale investments with unrealized losses, Fair Value, Total | 116,421 | 72,526
Available-for-sale investments with unrealized losses, Unrealized Loss, Total | 7,775 | $ 966
U.S. Treasury obligations |  |
Debt Securities, Available-for-sale [Line Items] |  |
Available-for-sale investments with unrealized losses, Less than 12 months, Fair Value | 2,244 |
Available-for-sale investments with unrealized losses, Less than 12 months, Unrealized Loss | 100 |
Available-for-sale investments with unrealized losses, 12 months or longer, Fair Value | 0 |
Available-for-sale investments with unrealized losses, 12 months or longer, Unrealized Loss | 0 |
Available-for-sale investments with unrealized losses, Fair Value, Total | 2,244 |
Available-for-sale investments with unrealized losses, Unrealized Loss, Total | $ 100 |

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