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

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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