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Schedule of Unrealized Loss on Available-for-Sale Investments (Detail) - USD ($) $ in Thousands | Jun. 26, 2021 | Dec. 26, 2020
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Debt Securities, Available-for-sale [Line Items] |  |
Available-for-sale investments with unrealized losses, Less than 12 months, Fair Value |  | $ 3,222
Available-for-sale investments with unrealized losses, Less than 12 months, Unrealized Loss |  | 98
Available-for-sale investments with unrealized losses, Fair Value, Total |  | 3,222
Available-for-sale investments with unrealized losses, Unrealized Loss, Total |  | 98
Asset-backed securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Available-for-sale investments with unrealized losses, Less than 12 months, Fair Value |  | 541
Available-for-sale investments with unrealized losses, Less than 12 months, Unrealized Loss |  | 26
Available-for-sale investments with unrealized losses, Fair Value, Total |  | 541
Available-for-sale investments with unrealized losses, Unrealized Loss, Total |  | 26
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 | $ 52,720 | 2,681
Available-for-sale investments with unrealized losses, Less than 12 months, Unrealized Loss | 238 | 72
Available-for-sale investments with unrealized losses, Fair Value, Total | 52,720 | 2,681
Available-for-sale investments with unrealized losses, Unrealized Loss, Total | $ 238 | $ 72

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- Definition Amount of accumulated unrealized loss on investments in debt and equity securities classified as available-for-sale in a continuous loss position. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=121645371&loc=d3e27337-111563 + Details
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- Definition This item represents the aggregate fair value of investments in debt and equity securities in an unrealized loss position which are categorized neither as held-to-maturity nor trading securities. + References No definition available. + Details
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- Definition Amount of accumulated unrealized loss on investments in debt and equity securities classified as available-for-sale that have been in a continuous loss position for less than twelve months. + References No definition available. + Details
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- Definition This item represents the aggregate fair value of investments in debt and equity securities categorized neither as held-to-maturity nor trading securities that have been in a continuous unrealized loss position for less than twelve months. + References No definition available. + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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