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Schedule of Unrealized Loss on Available-for-Sale Investments (Detail) - USD ($) $ in Thousands | Jun. 25, 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 | $ 111,061 | $ 94,621
Available-for-sale investments with unrealized losses, Less than 12 months, Unrealized Loss | 7,856 | 1,312
Available-for-sale investments with unrealized losses, 12 months or longer, Fair Value | 15,412 |
Available-for-sale investments with unrealized losses, 12 months or longer, Unrealized Loss | 1,445 |
Available-for-sale investments with unrealized losses, Fair Value, Total | 126,473 | 94,621
Available-for-sale investments with unrealized losses, Unrealized Loss, Total | 9,301 | 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 | 18,369 | 22,095
Available-for-sale investments with unrealized losses, Less than 12 months, Unrealized Loss | 2,135 | 346
Available-for-sale investments with unrealized losses, Fair Value, Total | 18,369 | 22,095
Available-for-sale investments with unrealized losses, Unrealized Loss, Total | 2,135 | 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 | 90,412 | 72,526
Available-for-sale investments with unrealized losses, Less than 12 months, Unrealized Loss | 5,659 | 966
Available-for-sale investments with unrealized losses, 12 months or longer, Fair Value | 15,412 |
Available-for-sale investments with unrealized losses, 12 months or longer, Unrealized Loss | 1,445 |
Available-for-sale investments with unrealized losses, Fair Value, Total | 105,824 | 72,526
Available-for-sale investments with unrealized losses, Unrealized Loss, Total | 7,104 | $ 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 | 2,280 |
Available-for-sale investments with unrealized losses, Less than 12 months, Unrealized Loss | 62 |
Available-for-sale investments with unrealized losses, Fair Value, Total | 2,280 |
Available-for-sale investments with unrealized losses, Unrealized Loss, Total | $ 62 |

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