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Amortized Cost and Fair Value of Available-for-Sale Investments (Detail) - USD ($) $ in Thousands | Sep. 24, 2022 | Dec. 25, 2021
--- | --- | ---
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | $ 173,398 | $ 171,449
Gross Unrealized Gains | 0 | 1,456
Gross Unrealized Losses | 11,304 | 1,312
Fair Value | 162,094 | 171,593
Money market investments |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 22,062 | 8,750
Fair Value | 22,062 | 8,750
Asset-backed securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 19,742 | 22,441
Gross Unrealized Losses | 2,666 | 346
Fair Value | 17,076 | 22,095
Corporate bonds and direct obligations of government agencies |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 129,250 | 137,916
Gross Unrealized Gains |  | 1,406
Gross Unrealized Losses | 8,536 | 966
Fair Value | 120,714 | 138,356
U.S. Treasury obligations |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 2,344 | 2,342
Gross Unrealized Gains |  | 50
Gross Unrealized Losses | 102 |
Fair Value | $ 2,242 | $ 2,392

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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://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (b) -URI https://asc.fasb.org/extlink&oid=126970911&loc=d3e27161-111563 + Details
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- Definition Amount, before tax, of unrealized loss 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://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c) -URI https://asc.fasb.org/extlink&oid=126970911&loc=d3e27161-111563 + Details
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