Amortized Cost and Fair Value of Available-for-Sale Investments (Detail) - USD ($) $ in Thousands	Jun. 25, 2022	Dec. 25, 2021
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 172,727	$ 171,449
Gross Unrealized Gains	29	1,456
Gross Unrealized Losses	9,301	1,312
Fair Value	163,455	171,593
Money market investments
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	25,368	8,750
Fair Value	25,368	8,750
Asset-backed securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	20,504	22,441
Gross Unrealized Losses	2,135	346
Fair Value	18,369	22,095
Corporate bonds and direct obligations of government agencies
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	124,513	137,916
Gross Unrealized Gains	29	1,406
Gross Unrealized Losses	7,104	966
Fair Value	117,438	138,356
U.S. Treasury obligations
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	2,342	2,342
Gross Unrealized Gains		50
Gross Unrealized Losses	62
Fair Value	$ 2,280	$ 2,392

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).

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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).

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Amortized cost of 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://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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